diff --git a/src/main/java/neqsim/processSimulation/measurementDevice/simpleFlowRegime/SevereSlugAnalyser.java b/src/main/java/neqsim/processSimulation/measurementDevice/simpleFlowRegime/SevereSlugAnalyser.java
index 01aff422e6..3edfe01d38 100644
--- a/src/main/java/neqsim/processSimulation/measurementDevice/simpleFlowRegime/SevereSlugAnalyser.java
+++ b/src/main/java/neqsim/processSimulation/measurementDevice/simpleFlowRegime/SevereSlugAnalyser.java
@@ -1,4 +1,5 @@
 package neqsim.processSimulation.measurementDevice.simpleFlowRegime;
+
 import java.util.Arrays;
 import java.util.Collections;
 import org.apache.logging.log4j.LogManager;
@@ -9,406 +10,454 @@
 import neqsim.thermodynamicOperations.ThermodynamicOperations;
 
 /**
- * <p>SevereSlugAnalyser class.</p>
+ * <p>
+ * SevereSlugAnalyser class.
+ * </p>
  *
  * @author ASMF
  * @version $Id: $Id
  */
 public class SevereSlugAnalyser extends MeasurementDeviceBaseClass {
   static Logger logger = LogManager.getLogger(SevereSlugAnalyser.class);
-    FluidSevereSlug fluidSevereS;
-    Pipe pipe;
-    SevereSlugAnalyser severeSlug;
-    Stream streamS;
-
-
-    final double gravAcc = neqsim.thermo.ThermodynamicConstantsInterface.gravity;
-    
-    //Severe slug problem
-    private double simulationTime = 200;
-    private double usl = 3.0;
-    private double usg = 0.5;
-    private double outletPressure = 100000.0;
-    private double temperature = 20.0;
-    private int numberOfTimeSteps = 20000;
-    private double internalDiameter = 0.0;
-    private double leftLength = 0.0;
-    private double rightLength = 0.0;
-    private double angle = 0.0;
-    
-    // These variables should not be changed by the user I guess. 
-    // But this can be done if the user has advanced knowledge about the problem. 
-    double alfaRiser = 0.0; // gas fraction in the riser 
-    double z = 0.0001; // some initial value to start the calculation
-    double lambdaStagnant = 0.0;
-    double uLevel = 0.0;// some initial value to start the calculation
-    double valveConstant = 0.0;
-    double normalPressure = 100000.0;
-    final double pi = neqsim.thermo.ThermodynamicConstantsInterface.pi;
-
-    double[] resPres;
-    double[] resTime;
-    double[] resLiqHoldUpRiser;
-    double[] resLiqHeight;
-    double[] resMixVelocity; 
-    double[] usgMap;
-    double[] uslMap;
-    double slugValue;
-    
-    //Simulation variables (calculated variables)
-    double deltaT;
-    double driftVel;
-    double flowDistCoeff;
-    double mixDensity;
-    double pressure;
-    double slugLength;
-    double transVel;
-    double Um; 
-    double UmOld;
-    double UsgL;
-    double UslL;
-    double UsgR;
-    double UslR;
-    double U;
-    double Re;
-    double lambda;
-    double friction;
-    double frictionStagnant;
-    double frictionValve;
-    double frictionTot;
-    double gravL;
-    double gravR;
-    double gravity;
-    double alfaRiserOld;
-    double zOld;
-    double Lg;
-    double pressureOld;
-    double alfaLeft;
-    double gasDensity;
-    double n;
-    double gamma1;
-    double gamma2;
-    double gamma;
-    double holdUp1;
-    double holdUp2;
-    double holdUp;
-    double function2;
-    double function1;
-
-    
-    double iter;
-
-    String flowPattern;
-
-    // This constructor is used for the "default" values
-    SevereSlugAnalyser(){
-      this.setSuperficialGasVelocity(usl);
-      this.setSuperficialGasVelocity(usg);
-      this.setOutletPressure(outletPressure);
-      this.setTemperature(temperature);
-      this.setSimulationTime(simulationTime);
-      this.setNumberOfTimeSteps(numberOfTimeSteps);
-            
-    }
-    
-    // This constructor is used for the user input of superficial liquid and gas velocities,
-    // and the rest will be the default values
-    SevereSlugAnalyser(double usl, double usg){
-      this.setSuperficialLiquidVelocity(usl);
-      this.setSuperficialGasVelocity(usg);
-      this.setOutletPressure(outletPressure);
-      this.setTemperature(temperature);
-      this.setSimulationTime(simulationTime);
-      this.setNumberOfTimeSteps(numberOfTimeSteps);      
-    }
-    
-    // This constructor is used for the user input of superficial liquid and gas velocities, outletPressure,
-    // temperature, simulationTime, numberOfTimeSteps
-    // and the rest will be the default values
-    SevereSlugAnalyser(double usl, double usg, double outletPressure, double temperature, double simulationTime, int numberOfTimeSteps){
-      this.setSuperficialLiquidVelocity(usl);
-      this.setSuperficialGasVelocity(usg);
-      this.setOutletPressure(outletPressure);
-      this.setTemperature(temperature);
-      this.setSimulationTime(simulationTime);
-      this.setNumberOfTimeSteps(numberOfTimeSteps);      
-    }
+  FluidSevereSlug fluidSevereS;
+  Pipe pipe;
+  SevereSlugAnalyser severeSlug;
+  Stream streamS;
+
+
+  final double gravAcc = neqsim.thermo.ThermodynamicConstantsInterface.gravity;
+
+  // Severe slug problem
+  private double simulationTime = 200;
+  private double usl = 3.0;
+  private double usg = 0.5;
+  private double outletPressure = 100000.0;
+  private double temperature = 20.0;
+  private int numberOfTimeSteps = 20000;
+  private double internalDiameter = 0.0;
+  private double leftLength = 0.0;
+  private double rightLength = 0.0;
+  private double angle = 0.0;
+
+  // These variables should not be changed by the user I guess.
+  // But this can be done if the user has advanced knowledge about the problem.
+  double alfaRiser = 0.0; // gas fraction in the riser
+  double z = 0.0001; // some initial value to start the calculation
+  double lambdaStagnant = 0.0;
+  double uLevel = 0.0;// some initial value to start the calculation
+  double valveConstant = 0.0;
+  double normalPressure = 100000.0;
+  final double pi = neqsim.thermo.ThermodynamicConstantsInterface.pi;
+
+  double[] resPres;
+  double[] resTime;
+  double[] resLiqHoldUpRiser;
+  double[] resLiqHeight;
+  double[] resMixVelocity;
+  double[] usgMap;
+  double[] uslMap;
+  double slugValue;
+
+  // Simulation variables (calculated variables)
+  double deltaT;
+  double driftVel;
+  double flowDistCoeff;
+  double mixDensity;
+  double pressure;
+  double slugLength;
+  double transVel;
+  double Um;
+  double UmOld;
+  double UsgL;
+  double UslL;
+  double UsgR;
+  double UslR;
+  double U;
+  double Re;
+  double lambda;
+  double friction;
+  double frictionStagnant;
+  double frictionValve;
+  double frictionTot;
+  double gravL;
+  double gravR;
+  double gravity;
+  double alfaRiserOld;
+  double zOld;
+  double Lg;
+  double pressureOld;
+  double alfaLeft;
+  double gasDensity;
+  double n;
+  double gamma1;
+  double gamma2;
+  double gamma;
+  double holdUp1;
+  double holdUp2;
+  double holdUp;
+  double function2;
+  double function1;
+
+
+  double iter;
+
+  String flowPattern;
+
+  // This constructor is used for the "default" values
+  SevereSlugAnalyser() {
+    this.setSuperficialGasVelocity(usl);
+    this.setSuperficialGasVelocity(usg);
+    this.setOutletPressure(outletPressure);
+    this.setTemperature(temperature);
+    this.setSimulationTime(simulationTime);
+    this.setNumberOfTimeSteps(numberOfTimeSteps);
 
-    SevereSlugAnalyser(SystemInterface fluid, Pipe pipe, double outletPressure, double temperature, double simulationTime, int numberOfTimeSteps){
-      ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
-      ops.TPflash();
-      fluid.initProperties();
-      if (fluid.getNumberOfPhases() == 2){
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      else{
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea() + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      this.setSuperficialLiquidVelocity(usl);
-      usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
-      this.setSuperficialGasVelocity(usg);
-      this.setOutletPressure(outletPressure);
-      this.setTemperature(temperature);
-      this.setSimulationTime(simulationTime);
-      this.setNumberOfTimeSteps(numberOfTimeSteps);      
-    }
+  }
 
-    SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength, double rightLength,  double angle, double outletPressure, double temperature, double simulationTime, int numberOfTimeSteps){
-      pipe = new Pipe(internalDiameter, leftLength, rightLength, angle);
-      streamS = stream;
-      SystemInterface fluid = stream.getThermoSystem();
-      ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
-      ops.TPflash();
-      fluid.initProperties();
-      if (fluid.getNumberOfPhases() == 2){
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      else{
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea() + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      fluidSevereS = new FluidSevereSlug(fluid);
-      usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
+  // This constructor is used for the user input of superficial liquid and gas velocities,
+  // and the rest will be the default values
+  SevereSlugAnalyser(double usl, double usg) {
+    this.setSuperficialLiquidVelocity(usl);
+    this.setSuperficialGasVelocity(usg);
+    this.setOutletPressure(outletPressure);
+    this.setTemperature(temperature);
+    this.setSimulationTime(simulationTime);
+    this.setNumberOfTimeSteps(numberOfTimeSteps);
+  }
 
-      severeSlug = new SevereSlugAnalyser(usl, usg, outletPressure, temperature, simulationTime,
-          numberOfTimeSteps);
-    }
+  // This constructor is used for the user input of superficial liquid and gas velocities,
+  // outletPressure,
+  // temperature, simulationTime, numberOfTimeSteps
+  // and the rest will be the default values
+  SevereSlugAnalyser(double usl, double usg, double outletPressure, double temperature,
+      double simulationTime, int numberOfTimeSteps) {
+    this.setSuperficialLiquidVelocity(usl);
+    this.setSuperficialGasVelocity(usg);
+    this.setOutletPressure(outletPressure);
+    this.setTemperature(temperature);
+    this.setSimulationTime(simulationTime);
+    this.setNumberOfTimeSteps(numberOfTimeSteps);
+  }
 
-    SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength,
-        double rightLength, double angle, double simulationTime, int numberOfTimeSteps) {
-      this(stream, internalDiameter, leftLength, rightLength, angle, stream.getPressure("Pa"),
-          stream.getTemperature("C"), simulationTime, numberOfTimeSteps);
-    }
+  SevereSlugAnalyser(SystemInterface fluid, Pipe pipe, double outletPressure, double temperature,
+      double simulationTime, int numberOfTimeSteps) {
+    ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
+    ops.TPflash();
+    fluid.initProperties();
+    if (fluid.getNumberOfPhases() == 2) {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
+    } else {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea()
+          + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
+    }
+    this.setSuperficialLiquidVelocity(usl);
+    usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
+    this.setSuperficialGasVelocity(usg);
+    this.setOutletPressure(outletPressure);
+    this.setTemperature(temperature);
+    this.setSimulationTime(simulationTime);
+    this.setNumberOfTimeSteps(numberOfTimeSteps);
+  }
+
+  SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength, double rightLength,
+      double angle, double outletPressure, double temperature, double simulationTime,
+      int numberOfTimeSteps) {
+    pipe = new Pipe(internalDiameter, leftLength, rightLength, angle);
+    streamS = stream;
+    SystemInterface fluid = stream.getThermoSystem();
+    ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
+    ops.TPflash();
+    fluid.initProperties();
+    if (fluid.getNumberOfPhases() == 2) {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
+    } else {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea()
+          + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
+    }
+    fluidSevereS = new FluidSevereSlug(fluid);
+    usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
+
+    severeSlug = new SevereSlugAnalyser(usl, usg, outletPressure, temperature, simulationTime,
+        numberOfTimeSteps);
+  }
 
-    SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength,
-    double rightLength, double angle) {
+  SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength, double rightLength,
+      double angle, double simulationTime, int numberOfTimeSteps) {
     this(stream, internalDiameter, leftLength, rightLength, angle, stream.getPressure("Pa"),
-      stream.getTemperature("C"), 500.0, 50000);
-}
+        stream.getTemperature("C"), simulationTime, numberOfTimeSteps);
+  }
 
-    SevereSlugAnalyser(double outletPressure, double temperature, double simulationTime, int numberOfTimeSteps){
-      this.setSuperficialLiquidVelocity(usl);
-      this.setSuperficialGasVelocity(usg);
-      this.setOutletPressure(outletPressure);
-      this.setTemperature(temperature);
-      this.setSimulationTime(simulationTime);
-      this.setNumberOfTimeSteps(numberOfTimeSteps);      
-    }
+  SevereSlugAnalyser(Stream stream, double internalDiameter, double leftLength, double rightLength,
+      double angle) {
+    this(stream, internalDiameter, leftLength, rightLength, angle, stream.getPressure("Pa"),
+        stream.getTemperature("C"), 500.0, 50000);
+  }
 
+  SevereSlugAnalyser(double outletPressure, double temperature, double simulationTime,
+      int numberOfTimeSteps) {
+    this.setSuperficialLiquidVelocity(usl);
+    this.setSuperficialGasVelocity(usg);
+    this.setOutletPressure(outletPressure);
+    this.setTemperature(temperature);
+    this.setSimulationTime(simulationTime);
+    this.setNumberOfTimeSteps(numberOfTimeSteps);
+  }
 
-    // Encapsulation
-    // 1. Superficial Liquid Velocity Encapsulation
-    /**
-     * <p>setSuperficialLiquidVelocity.</p>
-     *
-     * @param usl a double
-     */
-    public void setSuperficialLiquidVelocity(double usl) {
-      this.usl = usl;
-    }
-    
-    /**
-     * <p>getSuperficialLiquidVelocity.</p>
-     *
-     * @return a double
-     */
-    public double getSuperficialLiquidVelocity() {
-      return usl;
-    }
-    
-    // 2. Superficial Gas Velocity Encapsulation
-    /**
-     * <p>setSuperficialGasVelocity.</p>
-     *
-     * @param usg a double
-     */
-    public void setSuperficialGasVelocity(double usg) {
-      this.usg = usg;
-    }
-    
-    /**
-     * <p>getSuperficialGasVelocity.</p>
-     *
-     * @return a double
-     */
-    public double getSuperficialGasVelocity() {
-      return usg;
-    }
-    
-    /**
-     * <p>Getter for the field <code>flowPattern</code>.</p>
-     *
-     * @return a {@link java.lang.String} object
-     */
-    public String getFlowPattern() {
-      return flowPattern;
-    }
 
-    /**
-     * <p>Getter for the field <code>slugValue</code>.</p>
-     *
-     * @return a double
-     */
-    public double getSlugValue() {
-      return slugValue;
-    }
+  // Encapsulation
+  // 1. Superficial Liquid Velocity Encapsulation
+  /**
+   * <p>
+   * setSuperficialLiquidVelocity.
+   * </p>
+   *
+   * @param usl a double
+   */
+  public void setSuperficialLiquidVelocity(double usl) {
+    this.usl = usl;
+  }
 
-    // 3. Pipe Outlet Pressure Encapsulation
-    /**
-     * <p>Setter for the field <code>outletPressure</code>.</p>
-     *
-     * @param outletPressure a double
-     */
-    public void setOutletPressure(double outletPressure) {
-      this.outletPressure = outletPressure;
-    }
-    
-    /**
-     * <p>Getter for the field <code>outletPressure</code>.</p>
-     *
-     * @return a double
-     */
-    public double getOutletPressure() {
-      return outletPressure;
-    }
-    
-    // 4. Temperature Encapsulation
-    /**
-     * <p>Setter for the field <code>temperature</code>.</p>
-     *
-     * @param temperature a double
-     */
-    public void setTemperature(double temperature) {
-      this.temperature = temperature;
-    }
-    
-    /**
-     * <p>Getter for the field <code>temperature</code>.</p>
-     *
-     * @return a double
-     */
-    public double getTemperature() {
-      return temperature;
-    }
-    
-    // 5. Number of Time Steps Encapsulation
-    /**
-     * <p>Setter for the field <code>numberOfTimeSteps</code>.</p>
-     *
-     * @param numberOfTimeSteps a int
-     */
-    public void setNumberOfTimeSteps(int numberOfTimeSteps) {
-      this.numberOfTimeSteps = numberOfTimeSteps;
-    }
-    
-    /**
-     * <p>Getter for the field <code>numberOfTimeSteps</code>.</p>
-     *
-     * @return a int
-     */
-    public int getNumberOfTimeSteps() {
-      return numberOfTimeSteps;
-    }
-    
-    // 6. Simulation Time Encapsulation
-    /**
-     * <p>Setter for the field <code>simulationTime</code>.</p>
-     *
-     * @param simulationTime a double
-     */
-    public void setSimulationTime(double simulationTime) {
-      this.simulationTime = simulationTime;
-    }
-    
-    /**
-     * <p>Getter for the field <code>simulationTime</code>.</p>
-     *
-     * @return a double
-     */
-    public double getSimulationTime() {
-      return simulationTime;
-    }
-    
-    // Method 1: Calculating the universal gas constant
-     /**
-      * <p>gasConst.</p>
-      *
-      * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
-      * @return a double
-      */
-     public double gasConst(FluidSevereSlug fluid) {    
-        return 8.314 / fluid.getMolecularWeight() * (273.15 + temperature);    
-      }
-    
-    //Declare the variables for resuts after creating an object Severe slug with required number of steps.
-    
-    /**
-     * <p>slugHoldUp.</p>
-     *
-     * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-     * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
-     * @return a double
-     */
-    public double slugHoldUp (Pipe pipe, SevereSlugAnalyser severeSlug){
-      double Udrift;
-      double C0 = 1.2;
-      double Umix;
-
-      Umix = severeSlug.getSuperficialGasVelocity() + severeSlug.getSuperficialLiquidVelocity();
-      Udrift = Math.sqrt(gravAcc*pipe.getInternalDiameter());
-      holdUp = 1 - severeSlug.getSuperficialGasVelocity()/(C0 * Umix + Udrift);
-      return holdUp;
-  }  
+  /**
+   * <p>
+   * getSuperficialLiquidVelocity.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getSuperficialLiquidVelocity() {
+    return usl;
+  }
+
+  // 2. Superficial Gas Velocity Encapsulation
+  /**
+   * <p>
+   * setSuperficialGasVelocity.
+   * </p>
+   *
+   * @param usg a double
+   */
+  public void setSuperficialGasVelocity(double usg) {
+    this.usg = usg;
+  }
+
+  /**
+   * <p>
+   * getSuperficialGasVelocity.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getSuperficialGasVelocity() {
+    return usg;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>flowPattern</code>.
+   * </p>
+   *
+   * @return a {@link java.lang.String} object
+   */
+  public String getFlowPattern() {
+    return flowPattern;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>slugValue</code>.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getSlugValue() {
+    return slugValue;
+  }
+
+  // 3. Pipe Outlet Pressure Encapsulation
+  /**
+   * <p>
+   * Setter for the field <code>outletPressure</code>.
+   * </p>
+   *
+   * @param outletPressure a double
+   */
+  public void setOutletPressure(double outletPressure) {
+    this.outletPressure = outletPressure;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>outletPressure</code>.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getOutletPressure() {
+    return outletPressure;
+  }
+
+  // 4. Temperature Encapsulation
+  /**
+   * <p>
+   * Setter for the field <code>temperature</code>.
+   * </p>
+   *
+   * @param temperature a double
+   */
+  public void setTemperature(double temperature) {
+    this.temperature = temperature;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>temperature</code>.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getTemperature() {
+    return temperature;
+  }
+
+  // 5. Number of Time Steps Encapsulation
+  /**
+   * <p>
+   * Setter for the field <code>numberOfTimeSteps</code>.
+   * </p>
+   *
+   * @param numberOfTimeSteps a int
+   */
+  public void setNumberOfTimeSteps(int numberOfTimeSteps) {
+    this.numberOfTimeSteps = numberOfTimeSteps;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>numberOfTimeSteps</code>.
+   * </p>
+   *
+   * @return a int
+   */
+  public int getNumberOfTimeSteps() {
+    return numberOfTimeSteps;
+  }
+
+  // 6. Simulation Time Encapsulation
+  /**
+   * <p>
+   * Setter for the field <code>simulationTime</code>.
+   * </p>
+   *
+   * @param simulationTime a double
+   */
+  public void setSimulationTime(double simulationTime) {
+    this.simulationTime = simulationTime;
+  }
+
+  /**
+   * <p>
+   * Getter for the field <code>simulationTime</code>.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getSimulationTime() {
+    return simulationTime;
+  }
 
+  // Method 1: Calculating the universal gas constant
   /**
-   * <p>stratifiedHoldUp.</p>
+   * <p>
+   * gasConst.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @return a double
+   */
+  public double gasConst(FluidSevereSlug fluid) {
+    return 8.314 / fluid.getMolecularWeight() * (273.15 + temperature);
+  }
+
+  // Declare the variables for resuts after creating an object Severe slug with required number of
+  // steps.
+
+  /**
+   * <p>
+   * slugHoldUp.
+   * </p>
    *
-   * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
    * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-   * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
    * @return a double
    */
-  public double stratifiedHoldUp (FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug){
-    Re = fluid.getLiqDensity()*severeSlug.getSuperficialLiquidVelocity()*pipe.getInternalDiameter()/(fluid.getliqVisc());
+  public double slugHoldUp(Pipe pipe, SevereSlugAnalyser severeSlug) {
+    double Udrift;
+    double C0 = 1.2;
+    double Umix;
+
+    Umix = severeSlug.getSuperficialGasVelocity() + severeSlug.getSuperficialLiquidVelocity();
+    Udrift = Math.sqrt(gravAcc * pipe.getInternalDiameter());
+    holdUp = 1 - severeSlug.getSuperficialGasVelocity() / (C0 * Umix + Udrift);
+    return holdUp;
+  }
+
+  /**
+   * <p>
+   * stratifiedHoldUp.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
+   * @return a double
+   */
+  public double stratifiedHoldUp(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
+    Re = fluid.getLiqDensity() * severeSlug.getSuperficialLiquidVelocity()
+        * pipe.getInternalDiameter() / (fluid.getliqVisc());
     lambda = Math.max(0.34 * Math.pow(Re, -0.25), 64 / Re);
-    if (0.34 * Math.pow(Re, -0.25) > 64 / Re){
+    if (0.34 * Math.pow(Re, -0.25) > 64 / Re) {
       n = 0.25;
-    } 
-    else{
-     n = 1;
+    } else {
+      n = 1;
     }
-    friction=0.5*lambda*Math.pow(severeSlug.getSuperficialLiquidVelocity(),2)/(gravAcc*Math.sin(pipe.getAngle("Radian"))*pipe.getInternalDiameter());
+    friction = 0.5 * lambda * Math.pow(severeSlug.getSuperficialLiquidVelocity(), 2)
+        / (gravAcc * Math.sin(pipe.getAngle("Radian")) * pipe.getInternalDiameter());
 
     gamma1 = 0.1;
     gamma2 = 2.2;
     iter = 0;
-    while(Math.abs(gamma2 - gamma1) > 1e-5 && iter < 200){
+    while (Math.abs(gamma2 - gamma1) > 1e-5 && iter < 200) {
 
-      holdUp2 = (gamma2 - 0.5*Math.sin(2*gamma2))/(pi);
-      function2 = Math.pow(holdUp2,3)*Math.pow((pi/gamma2),(n+1))-friction;
+      holdUp2 = (gamma2 - 0.5 * Math.sin(2 * gamma2)) / (pi);
+      function2 = Math.pow(holdUp2, 3) * Math.pow((pi / gamma2), (n + 1)) - friction;
 
-      holdUp1 = (gamma1 - 0.5*Math.sin(2*gamma1))/(pi);
-      function1 = Math.pow(holdUp1,3)*Math.pow((pi/gamma1),(n+1))-friction;
+      holdUp1 = (gamma1 - 0.5 * Math.sin(2 * gamma1)) / (pi);
+      function1 = Math.pow(holdUp1, 3) * Math.pow((pi / gamma1), (n + 1)) - friction;
 
-      gamma = gamma2 - function2*(gamma2 - gamma1)/(function2 - function1);
-      if (gamma < 0){
-        if (gamma2 != 0.1)
-        {
+      gamma = gamma2 - function2 * (gamma2 - gamma1) / (function2 - function1);
+      if (gamma < 0) {
+        if (gamma2 != 0.1) {
           gamma = 0.1;
-        }
-        else{
+        } else {
           gamma = 0.2;
         }
       }
-      if (gamma > 3.00){
-        if (gamma2 != 2.99)
-        {
+      if (gamma > 3.00) {
+        if (gamma2 != 2.99) {
           gamma = 2.99;
-        }
-        else{
+        } else {
           gamma = 2.97;
         }
       }
-      
+
       gamma1 = gamma2;
       gamma2 = gamma;
       iter = iter + 1;
@@ -416,346 +465,388 @@ public double stratifiedHoldUp (FluidSevereSlug fluid, Pipe pipe, SevereSlugAnal
 
     if (iter == 199) {
       logger.debug("Could not find solution for stratified flow holdup");
-    }
-    else{
-      holdUp = (gamma - 0.5*Math.sin(2*gamma))/(pi);
+    } else {
+      holdUp = (gamma - 0.5 * Math.sin(2 * gamma)) / (pi);
 
     }
     return holdUp;
-}
-    
-    // Passing 3 objects as input parameters (fluid, pipe, severeSlug)
-    /**
-     * <p>runSevereSlug.</p>
-     *
-     * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
-     * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-     * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
-     */
-    public void runSevereSlug(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug){
-
-      resPres = new double[severeSlug.getNumberOfTimeSteps()]; 
-      resTime = new double[severeSlug.getNumberOfTimeSteps()];
-      resLiqHoldUpRiser = new double[severeSlug.getNumberOfTimeSteps()];
-      resLiqHeight = new double[severeSlug.getNumberOfTimeSteps()];
-      resMixVelocity = new double[severeSlug.getNumberOfTimeSteps()]; 
-
-      deltaT = 0.001; //severeSlug.getSimulationTime() / severeSlug.getNumberOfTimeSteps();
-      mixDensity = fluid.getLiqDensity();
-      pressure = severeSlug.getOutletPressure() + mixDensity * severeSlug.gravAcc * pipe.getRightLength(); // Initial condition
-      Um = severeSlug.getSuperficialGasVelocity();
-      holdUp = severeSlug.stratifiedHoldUp(fluid, pipe, severeSlug);
-      driftVel = 0.35 * Math.sqrt(gravAcc * pipe.getInternalDiameter()); // Drift velocity for the vertical flows
-      alfaLeft = 1 - holdUp;
-
-      for(int i = 0; i < severeSlug.numberOfTimeSteps; i++)
-      
-       {  
-          slugLength = -z  + pipe.getRightLength() * (1 - alfaRiser); //Slug Length          
-          Re = fluid.getLiqDensity() * Math.abs(Um) * pipe.getInternalDiameter() / fluid.getliqVisc(); // Reynolds number
-          lambda = Math.max(0.34 * Math.pow(Re, -0.25), 64 / Re); // friction factor
-          friction = 0.5 * lambda * fluid.getLiqDensity()* Um * Math.abs(Um) * slugLength / pipe.getInternalDiameter(); // frictional pressure loss
-          //Oscillation Friction
-          frictionStagnant = 0.5 * lambdaStagnant * fluid.getLiqDensity() * uLevel * Math.abs(uLevel) * slugLength  / pipe.getInternalDiameter();
-          //Valve Friction
-          frictionValve = valveConstant * fluid.getLiqDensity() * Um * Math.abs(Um);
-          //Total Friction
-          friction = friction + frictionStagnant + frictionValve;
-          // Gravity
-          gravL = -fluid.getLiqDensity() *  Math.abs(z) * gravAcc * Math.sin((pipe.getAngle("Radian")));
-          gravR = mixDensity * gravAcc * pipe.getRightLength();
-          gravity = gravL + gravR;
-
-          // Momentum Balance
-          UmOld = Um;
-          Um = UmOld + deltaT * ((pressure - severeSlug.outletPressure) - friction - gravity)
-                    / (-z * fluid.getLiqDensity() + pipe.getRightLength() * mixDensity);
-
-          // Slip Relation: Calculate translational velocity
-          if (Re < 2300) {
-            flowDistCoeff = 2;
-          } else {
-            flowDistCoeff = 1.2;
-          } 
-
-          transVel = flowDistCoeff * Um + driftVel;
-          // State Equation
-          // All cases, Case 1: Open Bend; Case 2: Blocked Bend; Case 3: Backflow
-          UsgL = (Um - severeSlug.getSuperficialLiquidVelocity()) *  ((Um > 0) ? 1 : 0) * ((z > 0) ? 1 : 0);
-
-          UslL =  ( severeSlug.getSuperficialLiquidVelocity() * ((z > 0) ? 1 : 0) + Um * ((z < 0) ? 1 : 0) ) *  ((Um > 0) ? 1 : 0) + 
-                           Um* ((Um < 0) ? 1 : 0);
-
-          UsgR = (alfaRiser * transVel * ((z > 0) ? 1 : 0) + Um * ((z < 0) ? 1 : 0)) * ((Um > 0) ? 1 : 0) + Um * ((Um < 0) ? 1 : 0);
-          UslR = (Um - alfaRiser * transVel) * ((Um > 0) ? 1 : 0) * ((z > 0) ? 1 : 0);
-
-          U = UsgL - UsgR - UslL + UslR; 
-          
-          // Riser vapour fraction
-          alfaRiserOld = alfaRiser;
-          alfaRiser = alfaRiserOld + 0.5 * deltaT * U / (pipe.getRightLength());
-          alfaRiser = Math.max(0.0, alfaRiser);
-          alfaRiser = Math.min(1.0, alfaRiser);
-
-          // Level
-          uLevel = (-severeSlug.getSuperficialLiquidVelocity() + Um); 
-          zOld = z;
-          z = zOld + deltaT * uLevel;
-          z = ((z < 0) ? 1 : 0) * z + ((z > 0) ? 1 : 0) * 0.0001;
-          uLevel = uLevel * ((z < 0) ? 1 : 0);
-
-          Lg = pipe.getLeftLength() + z;
-          pressureOld = pressure;
-          pressure = pressureOld + deltaT * (severeSlug.getSuperficialGasVelocity() * normalPressure - UsgL * pressureOld) / (Lg*alfaLeft) - deltaT *(pressureOld * uLevel) / (Lg*alfaLeft);
-
-          gasDensity = pressure / (fluid.getGasConstant()*(273.15 + severeSlug.getTemperature()));
-          mixDensity = alfaRiser * gasDensity + (1 - alfaRiser) * fluid.getLiqDensity();
-
-          resPres[i] = pressure/100000; 
-          resTime[i] = i*deltaT; 
-          resLiqHoldUpRiser[i] = (1-alfaRiser);
-          resLiqHeight[i] = z;
-          resMixVelocity[i] = Um; 
-          
-        }
-    }
+  }
 
-    /**
-     * <p>checkFlowRegime.</p>
-     *
-     * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
-     * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-     * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
-     * @return a {@link java.lang.String} object
-     */
-    public String checkFlowRegime(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug){
-      Double[] halfRes =new Double[severeSlug.getNumberOfTimeSteps()/2];
-      severeSlug.runSevereSlug(fluid, pipe, severeSlug);
-      double sum = 0;
-      for (int i = severeSlug.numberOfTimeSteps / 2; i < severeSlug.numberOfTimeSteps; i++) {
-        sum = sum + severeSlug.resPres[i];
-        halfRes[i - severeSlug.numberOfTimeSteps / 2] = severeSlug.resPres[i];
-      }
-      double meanValue =  sum / ((double) numberOfTimeSteps/2);
-      double max = Collections.max(Arrays.asList(halfRes));
-      slugValue = (max/meanValue) - 1;
-      double stratifiedHoldUp = stratifiedHoldUp (fluid, pipe, severeSlug);
-      logger.debug(stratifiedHoldUp);
-
-      double slugHoldUp = slugHoldUp(pipe,severeSlug);
-      logger.debug(slugHoldUp);
-      logger.debug("The severe slug value is " + slugValue);
-      if (slugValue > 0.1 && slugHoldUp > stratifiedHoldUp){
-        flowPattern = "Severe Slug";
-      }
-      else if(slugValue > 0.05 && slugHoldUp > stratifiedHoldUp){
-        flowPattern = "Severe Slug 2. Small pressure variations";
+  // Passing 3 objects as input parameters (fluid, pipe, severeSlug)
+  /**
+   * <p>
+   * runSevereSlug.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
+   */
+  public void runSevereSlug(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
+
+    resPres = new double[severeSlug.getNumberOfTimeSteps()];
+    resTime = new double[severeSlug.getNumberOfTimeSteps()];
+    resLiqHoldUpRiser = new double[severeSlug.getNumberOfTimeSteps()];
+    resLiqHeight = new double[severeSlug.getNumberOfTimeSteps()];
+    resMixVelocity = new double[severeSlug.getNumberOfTimeSteps()];
+
+    deltaT = 0.001; // severeSlug.getSimulationTime() / severeSlug.getNumberOfTimeSteps();
+    mixDensity = fluid.getLiqDensity();
+    pressure =
+        severeSlug.getOutletPressure() + mixDensity * severeSlug.gravAcc * pipe.getRightLength(); // Initial
+                                                                                                  // condition
+    Um = severeSlug.getSuperficialGasVelocity();
+    holdUp = severeSlug.stratifiedHoldUp(fluid, pipe, severeSlug);
+    driftVel = 0.35 * Math.sqrt(gravAcc * pipe.getInternalDiameter()); // Drift velocity for the
+                                                                       // vertical flows
+    alfaLeft = 1 - holdUp;
+
+    for (int i = 0; i < severeSlug.numberOfTimeSteps; i++)
+
+    {
+      slugLength = -z + pipe.getRightLength() * (1 - alfaRiser); // Slug Length
+      Re = fluid.getLiqDensity() * Math.abs(Um) * pipe.getInternalDiameter() / fluid.getliqVisc(); // Reynolds
+                                                                                                   // number
+      lambda = Math.max(0.34 * Math.pow(Re, -0.25), 64 / Re); // friction factor
+      friction = 0.5 * lambda * fluid.getLiqDensity() * Um * Math.abs(Um) * slugLength
+          / pipe.getInternalDiameter(); // frictional pressure loss
+      // Oscillation Friction
+      frictionStagnant = 0.5 * lambdaStagnant * fluid.getLiqDensity() * uLevel * Math.abs(uLevel)
+          * slugLength / pipe.getInternalDiameter();
+      // Valve Friction
+      frictionValve = valveConstant * fluid.getLiqDensity() * Um * Math.abs(Um);
+      // Total Friction
+      friction = friction + frictionStagnant + frictionValve;
+      // Gravity
+      gravL = -fluid.getLiqDensity() * Math.abs(z) * gravAcc * Math.sin((pipe.getAngle("Radian")));
+      gravR = mixDensity * gravAcc * pipe.getRightLength();
+      gravity = gravL + gravR;
+
+      // Momentum Balance
+      UmOld = Um;
+      Um = UmOld + deltaT * ((pressure - severeSlug.outletPressure) - friction - gravity)
+          / (-z * fluid.getLiqDensity() + pipe.getRightLength() * mixDensity);
+
+      // Slip Relation: Calculate translational velocity
+      if (Re < 2300) {
+        flowDistCoeff = 2;
+      } else {
+        flowDistCoeff = 1.2;
       }
-      else{
-        if (slugHoldUp<stratifiedHoldUp){
-          flowPattern = "Slug Flow";
+
+      transVel = flowDistCoeff * Um + driftVel;
+      // State Equation
+      // All cases, Case 1: Open Bend; Case 2: Blocked Bend; Case 3: Backflow
+      UsgL =
+          (Um - severeSlug.getSuperficialLiquidVelocity()) * ((Um > 0) ? 1 : 0) * ((z > 0) ? 1 : 0);
+
+      UslL =
+          (severeSlug.getSuperficialLiquidVelocity() * ((z > 0) ? 1 : 0) + Um * ((z < 0) ? 1 : 0))
+              * ((Um > 0) ? 1 : 0) + Um * ((Um < 0) ? 1 : 0);
+
+      UsgR =
+          (alfaRiser * transVel * ((z > 0) ? 1 : 0) + Um * ((z < 0) ? 1 : 0)) * ((Um > 0) ? 1 : 0)
+              + Um * ((Um < 0) ? 1 : 0);
+      UslR = (Um - alfaRiser * transVel) * ((Um > 0) ? 1 : 0) * ((z > 0) ? 1 : 0);
+
+      U = UsgL - UsgR - UslL + UslR;
+
+      // Riser vapour fraction
+      alfaRiserOld = alfaRiser;
+      alfaRiser = alfaRiserOld + 0.5 * deltaT * U / (pipe.getRightLength());
+      alfaRiser = Math.max(0.0, alfaRiser);
+      alfaRiser = Math.min(1.0, alfaRiser);
+
+      // Level
+      uLevel = (-severeSlug.getSuperficialLiquidVelocity() + Um);
+      zOld = z;
+      z = zOld + deltaT * uLevel;
+      z = ((z < 0) ? 1 : 0) * z + ((z > 0) ? 1 : 0) * 0.0001;
+      uLevel = uLevel * ((z < 0) ? 1 : 0);
+
+      Lg = pipe.getLeftLength() + z;
+      pressureOld = pressure;
+      pressure = pressureOld
+          + deltaT * (severeSlug.getSuperficialGasVelocity() * normalPressure - UsgL * pressureOld)
+              / (Lg * alfaLeft)
+          - deltaT * (pressureOld * uLevel) / (Lg * alfaLeft);
+
+      gasDensity = pressure / (fluid.getGasConstant() * (273.15 + severeSlug.getTemperature()));
+      mixDensity = alfaRiser * gasDensity + (1 - alfaRiser) * fluid.getLiqDensity();
+
+      resPres[i] = pressure / 100000;
+      resTime[i] = i * deltaT;
+      resLiqHoldUpRiser[i] = (1 - alfaRiser);
+      resLiqHeight[i] = z;
+      resMixVelocity[i] = Um;
+
+    }
+  }
+
+  /**
+   * <p>
+   * checkFlowRegime.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
+   * @return a {@link java.lang.String} object
+   */
+  public String checkFlowRegime(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
+    Double[] halfRes = new Double[severeSlug.getNumberOfTimeSteps() / 2];
+    severeSlug.runSevereSlug(fluid, pipe, severeSlug);
+    double sum = 0;
+    for (int i = severeSlug.numberOfTimeSteps / 2; i < severeSlug.numberOfTimeSteps; i++) {
+      sum = sum + severeSlug.resPres[i];
+      halfRes[i - severeSlug.numberOfTimeSteps / 2] = severeSlug.resPres[i];
+    }
+    double meanValue = sum / ((double) numberOfTimeSteps / 2);
+    double max = Collections.max(Arrays.asList(halfRes));
+    slugValue = (max / meanValue) - 1;
+    double stratifiedHoldUp = stratifiedHoldUp(fluid, pipe, severeSlug);
+    logger.debug(stratifiedHoldUp);
+
+    double slugHoldUp = slugHoldUp(pipe, severeSlug);
+    logger.debug(slugHoldUp);
+    logger.debug("The severe slug value is " + slugValue);
+    if (slugValue > 0.1 && slugHoldUp > stratifiedHoldUp) {
+      flowPattern = "Severe Slug";
+    } else if (slugValue > 0.05 && slugHoldUp > stratifiedHoldUp) {
+      flowPattern = "Severe Slug 2. Small pressure variations";
+    } else {
+      if (slugHoldUp < stratifiedHoldUp) {
+        flowPattern = "Slug Flow";
+      } else {
+        if (stratifiedHoldUp < 0.1) {
+          flowPattern = "Liquid droplets flow";
+        }
+        if (stratifiedHoldUp > 0.9) {
+          flowPattern = "Gas droplets flow";
         }
-        else{
-          if(stratifiedHoldUp < 0.1)
-          {
-            flowPattern = "Liquid droplets flow";
-          }
-          if(stratifiedHoldUp > 0.9)
-          {
-            flowPattern = "Gas droplets flow";
-          }
-          if(stratifiedHoldUp > 0.1 && stratifiedHoldUp < 0.9) {
-            flowPattern = "Stratified Flow";
-          }
+        if (stratifiedHoldUp > 0.1 && stratifiedHoldUp < 0.9) {
+          flowPattern = "Stratified Flow";
         }
       }
-      logger.debug("Simulated flow regime is then: " + flowPattern);
-      return flowPattern;
     }
+    logger.debug("Simulated flow regime is then: " + flowPattern);
+    return flowPattern;
+  }
 
-    /**
-     * <p>getMeasuredValue.</p>
-     *
-     * @return a double
-     */
-    public double getMeasuredValue() {
-      SystemInterface fluid = streamS.getThermoSystem();
-      ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
-      ops.TPflash();
-      fluid.initProperties();
-      if (fluid.getNumberOfPhases() == 2){
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      else{
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea() + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      fluidSevereS = new FluidSevereSlug(fluid);
-      usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
-      severeSlug = new SevereSlugAnalyser(usl, usg,outletPressure, temperature, simulationTime, numberOfTimeSteps);
-      checkFlowRegime(fluidSevereS, pipe, severeSlug);
-      return slugValue;
-    }
+  /**
+   * <p>
+   * getMeasuredValue.
+   * </p>
+   *
+   * @return a double
+   */
+  public double getMeasuredValue() {
+    SystemInterface fluid = streamS.getThermoSystem();
+    ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
+    ops.TPflash();
+    fluid.initProperties();
+    if (fluid.getNumberOfPhases() == 2) {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
+    } else {
+      usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea()
+          + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
+    }
+    fluidSevereS = new FluidSevereSlug(fluid);
+    usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
+    severeSlug = new SevereSlugAnalyser(usl, usg, outletPressure, temperature, simulationTime,
+        numberOfTimeSteps);
+    checkFlowRegime(fluidSevereS, pipe, severeSlug);
+    return slugValue;
+  }
 
-    /**
-     * <p>getPredictedFlowRegime.</p>
-     *
-     * @return a {@link java.lang.String} object
-     */
-    public String getPredictedFlowRegime() {
-      logger.debug(angle);
-      SystemInterface fluid = streamS.getThermoSystem();
-      ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
-      ops.TPflash();
-      fluid.initProperties();
-      if (fluid.getNumberOfPhases() == 1){
-        flowPattern = "Single Phase";
-      }
-      else if(pipe.getAngle("Radian") <= 0.0){
-        flowPattern = "Regime cannot be detected (angle < or = 0.0). Severe slug is not possible";
-      }
-      else{
-      if (fluid.getNumberOfPhases() == 2){
+  /**
+   * <p>
+   * getPredictedFlowRegime.
+   * </p>
+   *
+   * @return a {@link java.lang.String} object
+   */
+  public String getPredictedFlowRegime() {
+    logger.debug(angle);
+    SystemInterface fluid = streamS.getThermoSystem();
+    ThermodynamicOperations ops = new ThermodynamicOperations(fluid);
+    ops.TPflash();
+    fluid.initProperties();
+    if (fluid.getNumberOfPhases() == 1) {
+      flowPattern = "Single Phase";
+    } else if (pipe.getAngle("Radian") <= 0.0) {
+      flowPattern = "Regime cannot be detected (angle < or = 0.0). Severe slug is not possible";
+    } else {
+      if (fluid.getNumberOfPhases() == 2) {
         usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea();
-      }
-      else{
-        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea() + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
+      } else {
+        usl = fluid.getPhase(1).getFlowRate("m3/sec") / pipe.getArea()
+            + fluid.getPhase(2).getFlowRate("m3/sec") / pipe.getArea();
       }
       fluidSevereS = new FluidSevereSlug(fluid);
       usg = fluid.getPhase(0).getFlowRate("m3/sec") / pipe.getArea();
-      severeSlug = new SevereSlugAnalyser(usl, usg,outletPressure, temperature, simulationTime, numberOfTimeSteps);
+      severeSlug = new SevereSlugAnalyser(usl, usg, outletPressure, temperature, simulationTime,
+          numberOfTimeSteps);
       checkFlowRegime(fluidSevereS, pipe, severeSlug);
     }
-      return flowPattern;
-    }
+    return flowPattern;
+  }
 
-    /**
-     * <p>getMeasuredValue.</p>
-     *
-     * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
-     * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-     * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
-     * @return a double
-     */
-    public double getMeasuredValue(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
-      checkFlowRegime(fluid, pipe, severeSlug);
-      return slugValue;
-    }
+  /**
+   * <p>
+   * getMeasuredValue.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
+   * @return a double
+   */
+  public double getMeasuredValue(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
+    checkFlowRegime(fluid, pipe, severeSlug);
+    return slugValue;
+  }
 
-    /**
-     * <p>getPredictedFlowRegime.</p>
-     *
-     * @param fluid a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug} object
-     * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
-     * @param severeSlug a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser} object
-     * @return a {@link java.lang.String} object
-     */
-    public String getPredictedFlowRegime(FluidSevereSlug fluid, Pipe pipe, SevereSlugAnalyser severeSlug) {
-      checkFlowRegime(fluid, pipe, severeSlug);
-      return flowPattern;
-    }
+  /**
+   * <p>
+   * getPredictedFlowRegime.
+   * </p>
+   *
+   * @param fluid a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.FluidSevereSlug}
+   *        object
+   * @param pipe a {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.Pipe} object
+   * @param severeSlug a
+   *        {@link neqsim.processSimulation.measurementDevice.simpleFlowRegime.SevereSlugAnalyser}
+   *        object
+   * @return a {@link java.lang.String} object
+   */
+  public String getPredictedFlowRegime(FluidSevereSlug fluid, Pipe pipe,
+      SevereSlugAnalyser severeSlug) {
+    checkFlowRegime(fluid, pipe, severeSlug);
+    return flowPattern;
+  }
 
-    /**
-     * <p>main.</p>
-     *
-     * @param args an array of {@link java.lang.String} objects
-     */
-    public static void main(String args[]){
-      neqsim.thermo.system.SystemInterface testSystem =
-      new neqsim.thermo.system.SystemSrkEos((273.15 + 15.0), 10);
-      testSystem.addComponent("methane", 0.015, "MSm^3/day");
-      testSystem.addComponent("n-heptane", 0.0055, "MSm^3/day");
-      testSystem.setMixingRule(2);
-      testSystem.init(0);
-      Stream inputStream = new Stream("inputStream", testSystem);
-      SevereSlugAnalyser mySevereSlug4= new SevereSlugAnalyser (inputStream, 0.05, 167, 7.7, 2,100000.0,20.0, 200.0,20000);
-      logger.debug(inputStream.getFlowRate("kg/sec"));
-      mySevereSlug4.getPredictedFlowRegime();
-      // inputStream.setFlowRate(0.00001, "MSm^3/day");
-      // System.out.println(inputStream.getFlowRate("kg/sec"));
-      // mySevereSlug4.getPredictedFlowRegime();
-      
-    }
+  /**
+   * <p>
+   * main.
+   * </p>
+   *
+   * @param args an array of {@link java.lang.String} objects
+   */
+  public static void main(String args[]) {
+    neqsim.thermo.system.SystemInterface testSystem =
+        new neqsim.thermo.system.SystemSrkEos((273.15 + 15.0), 10);
+    testSystem.addComponent("methane", 0.015, "MSm^3/day");
+    testSystem.addComponent("n-heptane", 0.0055, "MSm^3/day");
+    testSystem.setMixingRule(2);
+    testSystem.init(0);
+    Stream inputStream = new Stream("inputStream", testSystem);
+    SevereSlugAnalyser mySevereSlug4 =
+        new SevereSlugAnalyser(inputStream, 0.05, 167, 7.7, 2, 100000.0, 20.0, 200.0, 20000);
+    logger.debug(inputStream.getFlowRate("kg/sec"));
+    mySevereSlug4.getPredictedFlowRegime();
+    // inputStream.setFlowRate(0.00001, "MSm^3/day");
+    // System.out.println(inputStream.getFlowRate("kg/sec"));
+    // mySevereSlug4.getPredictedFlowRegime();
+
+  }
 
 
-// To be implemented
-    // public void buildFlowMap(double ugmax, double ulmax, int numberOfStepsMap, FluidSevereSlug fluid, Pipe pipe, SevereSlug severeSlug){
-    //   String stability1;
-    //   String stability2;
-    //   for (double usl = 0.01; usl < ulmax; usl = usl + ulmax/numberOfStepsMap) { 
-    //     severeSlug.setSuperficialLiquidVelocity(usl);
-    //     double usg1 = 0.01;
-    //     double usg2 = ugmax;
-    //     double usg_sol;
-    //     iter = 0;
-
-
-    //     while(Math.abs(usg1 - usg2) > 1e-5 && iter < 200){
-
-    //       severeSlug.setSuperficialGasVelocity(usg1);
-    //       severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
-    //       function1 = severeSlug.slugValue - 0.05;
-
-    //       severeSlug.setSuperficialGasVelocity(usg2);
-    //       checkFlowRegime(fluid, pipe, severeSlug);
-    //       function2 = severeSlug.slugValue - 0.05;
-    
-    //       usg_sol = usg2 - function2*(usg2 - usg1)/(function2 - function1);
-
-    //       if (usg_sol < 0){
-    //         if (usg2 != 0.01)
-    //         {
-    //           usg2 = 0.01;
-    //         }
-    //         else{
-    //           usg2 = ugmax/2;
-    //         }
-    //       }
-    //       if (usg_sol > ugmax){
-    //         if (usg_sol != ugmax-0.01)
-    //         {
-    //           usg2 = ugmax-0.01;
-    //         }
-    //         else{
-    //           usg2 = 0.02;
-    //         }
-    //       }
-          
-    //       usg1 = usg2;
-    //       usg2 = usg;
-    //       iter = iter + 1;
-    //     }
-    
-    //     if (iter == 199){
-    //       System.out.println("Could not find the border");
-    //     }
-    //     else{
-          
-    //     }
-
-    //     severeSlug.setSuperficialLiquidVelocity(usl);
-    //     severeSlug.setSuperficialGasVelocity(0.01);
-    //     String flowPattern1 = severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
-    //     severeSlug.setSuperficialGasVelocity(ugmax);
-    //     String flowPattern2 = severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
-    //     if (flowPattern1 == "Severe Slug" || flowPattern1 == "Severe Slug 2. Small pressure variations"){
-    //       stability1 = "Not stable";
-    //     }
-    //     else{
-    //       stability1 = "Stable";
-    //     }
-    //     if (flowPattern2 == "Severe Slug" || flowPattern2 == "Severe Slug 2. Small pressure variations"){
-    //       stability2 = "Not stable";
-    //     }
-    //     else{
-    //       stability2 = "Stable";
-    //     }
-    //     if (flowPattern1 != flowPattern2){
-          
-    //     }
-
-    //}
-
-    //}
+  // To be implemented
+  // public void buildFlowMap(double ugmax, double ulmax, int numberOfStepsMap, FluidSevereSlug
+  // fluid, Pipe pipe, SevereSlug severeSlug){
+  // String stability1;
+  // String stability2;
+  // for (double usl = 0.01; usl < ulmax; usl = usl + ulmax/numberOfStepsMap) {
+  // severeSlug.setSuperficialLiquidVelocity(usl);
+  // double usg1 = 0.01;
+  // double usg2 = ugmax;
+  // double usg_sol;
+  // iter = 0;
+
+
+  // while(Math.abs(usg1 - usg2) > 1e-5 && iter < 200){
+
+  // severeSlug.setSuperficialGasVelocity(usg1);
+  // severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
+  // function1 = severeSlug.slugValue - 0.05;
+
+  // severeSlug.setSuperficialGasVelocity(usg2);
+  // checkFlowRegime(fluid, pipe, severeSlug);
+  // function2 = severeSlug.slugValue - 0.05;
+
+  // usg_sol = usg2 - function2*(usg2 - usg1)/(function2 - function1);
+
+  // if (usg_sol < 0){
+  // if (usg2 != 0.01)
+  // {
+  // usg2 = 0.01;
+  // }
+  // else{
+  // usg2 = ugmax/2;
+  // }
+  // }
+  // if (usg_sol > ugmax){
+  // if (usg_sol != ugmax-0.01)
+  // {
+  // usg2 = ugmax-0.01;
+  // }
+  // else{
+  // usg2 = 0.02;
+  // }
+  // }
+
+  // usg1 = usg2;
+  // usg2 = usg;
+  // iter = iter + 1;
+  // }
+
+  // if (iter == 199){
+  // System.out.println("Could not find the border");
+  // }
+  // else{
+
+  // }
+
+  // severeSlug.setSuperficialLiquidVelocity(usl);
+  // severeSlug.setSuperficialGasVelocity(0.01);
+  // String flowPattern1 = severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
+  // severeSlug.setSuperficialGasVelocity(ugmax);
+  // String flowPattern2 = severeSlug.checkFlowRegime(fluid, pipe, severeSlug);
+  // if (flowPattern1 == "Severe Slug" || flowPattern1 == "Severe Slug 2. Small pressure
+  // variations"){
+  // stability1 = "Not stable";
+  // }
+  // else{
+  // stability1 = "Stable";
+  // }
+  // if (flowPattern2 == "Severe Slug" || flowPattern2 == "Severe Slug 2. Small pressure
+  // variations"){
+  // stability2 = "Not stable";
+  // }
+  // else{
+  // stability2 = "Stable";
+  // }
+  // if (flowPattern1 != flowPattern2){
+
+  // }
+
+  // }
+
+  // }
 
 
-  }
+}
diff --git a/src/main/java/neqsim/processSimulation/processEquipment/pump/PumpChart.java b/src/main/java/neqsim/processSimulation/processEquipment/pump/PumpChart.java
index 70240e9028..890d2a3a96 100644
--- a/src/main/java/neqsim/processSimulation/processEquipment/pump/PumpChart.java
+++ b/src/main/java/neqsim/processSimulation/processEquipment/pump/PumpChart.java
@@ -20,346 +20,340 @@
  * @version $Id: $Id
  */
 public class PumpChart implements PumpChartInterface, java.io.Serializable {
-    private static final long serialVersionUID = 1000;
-    static Logger logger = LogManager.getLogger(PumpChart.class);
-    ArrayList<PumpCurve> chartValues = new ArrayList<PumpCurve>();
-    boolean isSurge = false;
-    double maxSpeedCurve = 0;
-    double minSpeedCurve = 1e10;
-    double refMW;
-    private String headUnit = "meter";
-    private boolean usePumpChart = false;
-    double refTemperature;
-    double refPressure;
-    double referenceSpeed = 1000.0;
-    double refZ;
-    private boolean useRealKappa = false;
-    double[] chartConditions = null;
-    final WeightedObservedPoints reducedHeadFitter = new WeightedObservedPoints();
-    final WeightedObservedPoints reducedFlowFitter = new WeightedObservedPoints();
-    final WeightedObservedPoints fanLawCorrectionFitter = new WeightedObservedPoints();
-    final WeightedObservedPoints reducedEfficiencyFitter = new WeightedObservedPoints();
-    PolynomialFunction reducedHeadFitterFunc = null;
-    PolynomialFunction reducedEfficiencyFunc = null;
-    PolynomialFunction fanLawCorrectionFunc = null;
-    double[] speed;
-    double[][] flow;
-    double[][] head;
-    double[][] efficiency;
-    double[][] redflow;
-    double[][] redhead;
-    double[][] redEfficiency;
-
-    /**
-     * <p>
-     * Constructor for PumpChart.
-     * </p>
-     */
-    public PumpChart() {}
-
-    /** {@inheritDoc} */
-    @Override
-    public void addCurve(double speed, double[] flow, double[] head, double[] efficiency) {
-        PumpCurve curve = new PumpCurve(speed, flow, head, efficiency);
-        chartValues.add(curve);
+  private static final long serialVersionUID = 1000;
+  static Logger logger = LogManager.getLogger(PumpChart.class);
+  ArrayList<PumpCurve> chartValues = new ArrayList<PumpCurve>();
+  boolean isSurge = false;
+  double maxSpeedCurve = 0;
+  double minSpeedCurve = 1e10;
+  double refMW;
+  private String headUnit = "meter";
+  private boolean usePumpChart = false;
+  double refTemperature;
+  double refPressure;
+  double referenceSpeed = 1000.0;
+  double refZ;
+  private boolean useRealKappa = false;
+  double[] chartConditions = null;
+  final WeightedObservedPoints reducedHeadFitter = new WeightedObservedPoints();
+  final WeightedObservedPoints reducedFlowFitter = new WeightedObservedPoints();
+  final WeightedObservedPoints fanLawCorrectionFitter = new WeightedObservedPoints();
+  final WeightedObservedPoints reducedEfficiencyFitter = new WeightedObservedPoints();
+  PolynomialFunction reducedHeadFitterFunc = null;
+  PolynomialFunction reducedEfficiencyFunc = null;
+  PolynomialFunction fanLawCorrectionFunc = null;
+  double[] speed;
+  double[][] flow;
+  double[][] head;
+  double[][] efficiency;
+  double[][] redflow;
+  double[][] redhead;
+  double[][] redEfficiency;
+
+  /**
+   * <p>
+   * Constructor for PumpChart.
+   * </p>
+   */
+  public PumpChart() {}
+
+  /** {@inheritDoc} */
+  @Override
+  public void addCurve(double speed, double[] flow, double[] head, double[] efficiency) {
+    PumpCurve curve = new PumpCurve(speed, flow, head, efficiency);
+    chartValues.add(curve);
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void setCurves(double[] chartConditions, double[] speed, double[][] flow, double[][] head,
+      double[][] efficiency) {
+    this.speed = speed;
+    this.head = head;
+    this.efficiency = efficiency;
+    this.flow = flow;
+
+    this.redhead = new double[head.length][head[0].length];
+    this.redEfficiency = new double[efficiency.length][efficiency[0].length];
+    this.redflow = new double[flow.length][flow[0].length];
+
+    for (int i = 0; i < speed.length; i++) {
+      if (speed[i] > maxSpeedCurve) {
+        maxSpeedCurve = speed[i];
+      }
+      if (speed[i] < minSpeedCurve) {
+        minSpeedCurve = speed[i];
+      }
+      PumpCurve curve = new PumpCurve(speed[i], flow[i], head[i], efficiency[i]);
+      chartValues.add(curve);
+      for (int j = 0; j < flow[i].length; j++) {
+        redflow[i][j] = flow[i][j] / speed[i];
+        redEfficiency[i][j] = efficiency[i][j];
+        redhead[i][j] = head[i][j] / speed[i] / speed[i];
+        reducedHeadFitter.add(redflow[i][j], redhead[i][j]);
+        reducedEfficiencyFitter.add(redflow[i][j], redEfficiency[i][j]);
+        // todo: MLLU: not correct. speed[0] should be the requested speed
+        double flowFanLaw = flow[i][j] * speed[i] / speed[0];
+        fanLawCorrectionFitter.add(speed[i] / speed[0], flow[i][j] / flowFanLaw);
+      }
     }
 
-    /** {@inheritDoc} */
-    @Override
-    public void setCurves(double[] chartConditions, double[] speed, double[][] flow,
-            double[][] head, double[][] efficiency) {
-        this.speed = speed;
-        this.head = head;
-        this.efficiency = efficiency;
-        this.flow = flow;
-
-        this.redhead = new double[head.length][head[0].length];
-        this.redEfficiency = new double[efficiency.length][efficiency[0].length];
-        this.redflow = new double[flow.length][flow[0].length];
-
-        for (int i = 0; i < speed.length; i++) {
-            if (speed[i] > maxSpeedCurve)
-                maxSpeedCurve = speed[i];
-            if (speed[i] < minSpeedCurve)
-                minSpeedCurve = speed[i];
-            PumpCurve curve = new PumpCurve(speed[i], flow[i], head[i], efficiency[i]);
-            chartValues.add(curve);
-            for (int j = 0; j < flow[i].length; j++) {
-                redflow[i][j] = flow[i][j] / speed[i];
-                redEfficiency[i][j] = efficiency[i][j];
-                redhead[i][j] = head[i][j] / speed[i] / speed[i];
-                reducedHeadFitter.add(redflow[i][j], redhead[i][j]);
-                reducedEfficiencyFitter.add(redflow[i][j], redEfficiency[i][j]);
-                double flowFanLaw = flow[i][j] * speed[i] / speed[0]; // MLLU: not correct. speed[0]
-                                                                      // should be the
-                                                                      // requested speed
-                fanLawCorrectionFitter.add(speed[i] / speed[0], flow[i][j] / flowFanLaw);
-            }
-        }
-
-        referenceSpeed = (maxSpeedCurve + minSpeedCurve) / 2.0;
-
-        PolynomialCurveFitter fitter = PolynomialCurveFitter.create(2);
-
-        reducedHeadFitterFunc = new PolynomialFunction(fitter.fit(reducedHeadFitter.toList()));
-        reducedEfficiencyFunc =
-                new PolynomialFunction(fitter.fit(reducedEfficiencyFitter.toList()));
-        fanLawCorrectionFunc = new PolynomialFunction(fitter.fit(fanLawCorrectionFitter.toList()));
-        setUsePumpChart(true);
-    }
-
-    /**
-     * <p>
-     * fitReducedCurve.
-     * </p>
-     */
-    public void fitReducedCurve() {}
-
-    /** {@inheritDoc} */
-    @Override
-    public double getHead(double flow, double speed) {
-        return reducedHeadFitterFunc.value(flow / speed) * speed * speed;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public double getEfficiency(double flow, double speed) {
-        return reducedEfficiencyFunc.value(flow / speed);
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public int getSpeed(double flow, double head) {
-        int iter = 1;
-        double error = 1.0, derrordspeed = 1.0;
-        double newspeed = referenceSpeed;
-        double newhead = 0.0;
-        double oldspeed = newspeed + 1.0;
-        double oldhead = getHead(flow, oldspeed);
-        double olderror = oldhead - head;
-        do {
-            iter++;
-            newhead = getHead(flow, newspeed);
-            error = newhead - head;
-            derrordspeed = (error - olderror) / (newspeed - oldspeed);
-            newspeed -= error / derrordspeed;
-            // System.out.println("speed " + newspeed);
-        } while (Math.abs(error) > 1e-6 && iter < 100);
-
-        // change speed to minimize
-        // Math.abs(head - reducedHeadFitterFunc.value(flow / speed) * speed * speed);
-        return (int) Math.round(newspeed);
-    }
-
-    /**
-     * <p>
-     * efficiency.
-     * </p>
-     *
-     * @param flow a double
-     * @param speed a double
-     * @return a double
-     */
-    public double efficiency(double flow, double speed) {
-        return 100.0;
-    }
-
-    /**
-     * <p>
-     * checkSurge1.
-     * </p>
-     *
-     * @param flow a double
-     * @param head a double
-     * @return a boolean
-     */
-    public boolean checkSurge1(double flow, double head) {
-        return false;
-    }
-
-    /**
-     * <p>
-     * checkSurge2.
-     * </p>
-     *
-     * @param flow a double
-     * @param speed a double
-     * @return a boolean
-     */
-    public boolean checkSurge2(double flow, double speed) {
-        return false;
-    }
-
-    /**
-     * <p>
-     * checkStoneWall.
-     * </p>
-     *
-     * @param flow a double
-     * @param speed a double
-     * @return a boolean
-     */
-    public boolean checkStoneWall(double flow, double speed) {
-        return false;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void setReferenceConditions(double refMW, double refTemperature, double refPressure,
-            double refZ) {
-        this.refMW = refMW;
-        this.refTemperature = refTemperature;
-        this.refPressure = refPressure;
-        this.refZ = refZ;
-    }
-
-    /**
-     * <p>
-     * main.
-     * </p>
-     *
-     * @param args an array of {@link java.lang.String} objects
-     */
-    public static void main(String[] args) {
-        SystemInterface testFluid = new SystemSrkEos(298.15, 50.0);
-        testFluid.addComponent("water", 1.0);
-        testFluid.setTemperature(20.0, "C");
-        testFluid.setPressure(1.0, "bara");
-        testFluid.setTotalFlowRate(1000.0, "kg/hr");
-
-        Stream stream_1 = new Stream("Stream1", testFluid);
-
-        Pump pump1 = new Pump("pump1", stream_1);
-        pump1.setOutletPressure(100.0);
-        // comp1.getAntiSurge().setActive(true);
-        pump1.setSpeed(12918);
-
-        double[] chartConditions = new double[] {0.3, 1.0, 1.0, 1.0};
-        // double[] speed = new double[] { 1000.0, 2000.0, 3000.0, 4000.0 };
-        // double[][] flow = new double[][] { { 453.2, 600.0, 750.0, 800.0 }, { 453.2,
-        // 600.0, 750.0, 800.0
-        // }, { 453.2, 600.0, 750.0, 800.0 }, { 453.2, 600.0, 750.0, 800.0 } };
-        // double[][] head = new double[][] { { 10000.0, 9000.0, 8000.0, 7500.0 }, {
-        // 10000.0, 9000.0, 8000.0, 7500.0 }, { 10000.0, 9000.0, 8000.0, 7500.0 }, {
-        // 10000.0, 9000.0, 8000.0, 7500.0 } };
-        // double[][] polyEff = new double[][] { {
-        // 90.0, 91.0, 89.0, 88.0 }, { 90.0, 91.0, 89.0, 88.0 }, { 90.0, 91.0, 89.0,
-        // 88.1 }, { 90.0, 91.0, 89.0, 88.1 } };
-
-        double[] speed = new double[] {12913, 12298, 11683, 11098, 10453, 9224, 8609, 8200};
-        double[][] flow = new double[][] {
-                {2789.1285, 3174.0375, 3689.2288, 4179.4503, 4570.2768, 4954.7728, 5246.0329,
-                        5661.0331},
-                {2571.1753, 2943.7254, 3440.2675, 3837.4448, 4253.0898, 4668.6643, 4997.1926,
-                        5387.4952},
-                {2415.3793, 2763.0706, 3141.7095, 3594.7436, 4047.6467, 4494.1889, 4853.7353,
-                        5138.7858},
-                {2247.2043, 2799.7342, 3178.3428, 3656.1551, 4102.778, 4394.1591, 4648.3224,
-                        4840.4998},
-                {2072.8397, 2463.9483, 2836.4078, 3202.5266, 3599.6333, 3978.0203, 4257.0022,
-                        4517.345},
-                {1835.9552, 2208.455, 2618.1322, 2940.8034, 3244.7852, 3530.1279, 3753.3738,
-                        3895.9746},
-                {1711.3386, 1965.8848, 2356.9431, 2685.9247, 3008.5154, 3337.2855, 3591.5092},
-                {1636.5807, 2002.8708, 2338.0319, 2642.1245, 2896.4894, 3113.6264, 3274.8764,
-                        3411.2977}};
-        double[][] head = new double[][] {
-                {80.0375, 78.8934, 76.2142, 71.8678, 67.0062, 60.6061, 53.0499, 39.728},
-                {72.2122, 71.8369, 68.9009, 65.8341, 60.7167, 54.702, 47.2749, 35.7471},
-                {65.1576, 64.5253, 62.6118, 59.1619, 54.0455, 47.0059, 39.195, 31.6387},
-                {58.6154, 56.9627, 54.6647, 50.4462, 44.4322, 38.4144, 32.9084, 28.8109},
-                {52.3295, 51.0573, 49.5283, 46.3326, 42.3685, 37.2502, 31.4884, 25.598},
-                {40.6578, 39.6416, 37.6008, 34.6603, 30.9503, 27.1116, 23.2713, 20.4546},
-                {35.2705, 34.6359, 32.7228, 31.0645, 27.0985, 22.7482, 18.0113},
-                {32.192, 31.1756, 29.1329, 26.833, 23.8909, 21.3324, 18.7726, 16.3403},};
-        double[][] efficiency = new double[][] {
-                {77.2452238409573, 79.4154186459363, 80.737960012489, 80.5229826589649,
-                        79.2210931638144, 75.4719133864634, 69.6034181197298, 58.7322388482707},
-                {77.0107837113504, 79.3069974136389, 80.8941189021135, 80.7190194665918,
-                        79.5313242980328, 75.5912622896367, 69.6846136362097, 60.0043057990909},
-                {77.0043065299874, 79.1690958847856, 80.8038169975675, 80.6543975614197,
-                        78.8532389102705, 73.6664774270613, 66.2735600426727, 57.671664571658},
-                {77.0716623789093, 80.4629750233093, 81.1390811169072, 79.6374242667478,
-                        75.380928428817, 69.5332969549779, 63.7997587622339, 58.8120614497758},
-                {76.9705872525642, 79.8335492585324, 80.9468133671171, 80.5806471927835,
-                        78.0462158225426, 73.0403707523258, 66.5572286338589, 59.8624822515064},
-                {77.5063036680357, 80.2056198362559, 81.0339108025933, 79.6085962687939,
-                        76.3814534404405, 70.8027503005902, 64.6437367160571, 60.5299349982342},
-                {77.8175271586685, 80.065165942218, 81.0631362122632, 79.8955051771299,
-                        76.1983240929369, 69.289982774309, 60.8567149372229},
-                {78.0924334304045, 80.9353551568667, 80.7904437766234, 78.8639325223295,
-                        75.2170936751143, 70.3105081673411, 65.5507568533569, 61.0391468300337}};
-
-        pump1.getPumpChart().setCurves(chartConditions, speed, flow, head, efficiency);
-        pump1.getPumpChart().setHeadUnit("kJ/kg");
-
-        neqsim.processSimulation.processSystem.ProcessSystem operations =
-                new neqsim.processSimulation.processSystem.ProcessSystem();
-        operations.add(stream_1);
-        operations.add(pump1);
-        operations.run();
-
-        System.out.println("pump power " + pump1.getPower());
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public boolean isUsePumpChart() {
-        return usePumpChart;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void setUsePumpChart(boolean usePumpChart) {
-        this.usePumpChart = usePumpChart;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public String getHeadUnit() {
-        return headUnit;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void setHeadUnit(String headUnit) {
-        this.headUnit = headUnit;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public boolean useRealKappa() {
-        return useRealKappa;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void setUseRealKappa(boolean useRealKappa) {
-        this.useRealKappa = useRealKappa;
-    }
-
-    /** {@inheritDoc} */
-    @Override
-    public void plot() {
-        neqsim.dataPresentation.JFreeChart.graph2b graph =
-                new neqsim.dataPresentation.JFreeChart.graph2b(flow, head,
-                        Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
-                        "head vs flow", "flow", "head");
-        graph.setVisible(true);
-        neqsim.dataPresentation.JFreeChart.graph2b graph2 =
-                new neqsim.dataPresentation.JFreeChart.graph2b(flow, efficiency,
-                        Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
-                        "eff vs flow", "flow", "eff");
-        graph2.setVisible(true);
-        neqsim.dataPresentation.JFreeChart.graph2b graph3 =
-                new neqsim.dataPresentation.JFreeChart.graph2b(redflow, redhead,
-                        Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
-                        "red head vs red flow", "red flow", "red head");
-        graph3.setVisible(true);
-        neqsim.dataPresentation.JFreeChart.graph2b graph4 =
-                new neqsim.dataPresentation.JFreeChart.graph2b(redflow, efficiency,
-                        Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
-                        "red eff vs red dflow", "red flow", "red eff");
-        graph4.setVisible(true);
-    }
+    referenceSpeed = (maxSpeedCurve + minSpeedCurve) / 2.0;
+
+    PolynomialCurveFitter fitter = PolynomialCurveFitter.create(2);
+
+    reducedHeadFitterFunc = new PolynomialFunction(fitter.fit(reducedHeadFitter.toList()));
+    reducedEfficiencyFunc = new PolynomialFunction(fitter.fit(reducedEfficiencyFitter.toList()));
+    fanLawCorrectionFunc = new PolynomialFunction(fitter.fit(fanLawCorrectionFitter.toList()));
+    setUsePumpChart(true);
+  }
+
+  /**
+   * <p>
+   * fitReducedCurve.
+   * </p>
+   */
+  public void fitReducedCurve() {}
+
+  /** {@inheritDoc} */
+  @Override
+  public double getHead(double flow, double speed) {
+    return reducedHeadFitterFunc.value(flow / speed) * speed * speed;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public double getEfficiency(double flow, double speed) {
+    return reducedEfficiencyFunc.value(flow / speed);
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public int getSpeed(double flow, double head) {
+    int iter = 1;
+    double error = 1.0;
+    double derrordspeed = 1.0;
+    double newspeed = referenceSpeed;
+    double newhead = 0.0;
+    double oldspeed = newspeed + 1.0;
+    double oldhead = getHead(flow, oldspeed);
+    double olderror = oldhead - head;
+    do {
+      iter++;
+      newhead = getHead(flow, newspeed);
+      error = newhead - head;
+      derrordspeed = (error - olderror) / (newspeed - oldspeed);
+      newspeed -= error / derrordspeed;
+      // System.out.println("speed " + newspeed);
+    } while (Math.abs(error) > 1e-6 && iter < 100);
+
+    // change speed to minimize
+    // Math.abs(head - reducedHeadFitterFunc.value(flow / speed) * speed * speed);
+    return (int) Math.round(newspeed);
+  }
+
+  /**
+   * <p>
+   * efficiency.
+   * </p>
+   *
+   * @param flow a double
+   * @param speed a double
+   * @return a double
+   */
+  public double efficiency(double flow, double speed) {
+    return 100.0;
+  }
+
+  /**
+   * <p>
+   * checkSurge1.
+   * </p>
+   *
+   * @param flow a double
+   * @param head a double
+   * @return a boolean
+   */
+  public boolean checkSurge1(double flow, double head) {
+    return false;
+  }
+
+  /**
+   * <p>
+   * checkSurge2.
+   * </p>
+   *
+   * @param flow a double
+   * @param speed a double
+   * @return a boolean
+   */
+  public boolean checkSurge2(double flow, double speed) {
+    return false;
+  }
+
+  /**
+   * <p>
+   * checkStoneWall.
+   * </p>
+   *
+   * @param flow a double
+   * @param speed a double
+   * @return a boolean
+   */
+  public boolean checkStoneWall(double flow, double speed) {
+    return false;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void setReferenceConditions(double refMW, double refTemperature, double refPressure,
+      double refZ) {
+    this.refMW = refMW;
+    this.refTemperature = refTemperature;
+    this.refPressure = refPressure;
+    this.refZ = refZ;
+  }
+
+  /**
+   * <p>
+   * main.
+   * </p>
+   *
+   * @param args an array of {@link java.lang.String} objects
+   */
+  public static void main(String[] args) {
+    SystemInterface testFluid = new SystemSrkEos(298.15, 50.0);
+    testFluid.addComponent("water", 1.0);
+    testFluid.setTemperature(20.0, "C");
+    testFluid.setPressure(1.0, "bara");
+    testFluid.setTotalFlowRate(1000.0, "kg/hr");
+
+    Stream stream_1 = new Stream("Stream1", testFluid);
+
+    Pump pump1 = new Pump("pump1", stream_1);
+    pump1.setOutletPressure(100.0);
+    // comp1.getAntiSurge().setActive(true);
+    pump1.setSpeed(12918);
+
+    double[] chartConditions = new double[] {0.3, 1.0, 1.0, 1.0};
+    // double[] speed = new double[] { 1000.0, 2000.0, 3000.0, 4000.0 };
+    // double[][] flow = new double[][] { { 453.2, 600.0, 750.0, 800.0 }, { 453.2,
+    // 600.0, 750.0, 800.0
+    // }, { 453.2, 600.0, 750.0, 800.0 }, { 453.2, 600.0, 750.0, 800.0 } };
+    // double[][] head = new double[][] { { 10000.0, 9000.0, 8000.0, 7500.0 }, {
+    // 10000.0, 9000.0, 8000.0, 7500.0 }, { 10000.0, 9000.0, 8000.0, 7500.0 }, {
+    // 10000.0, 9000.0, 8000.0, 7500.0 } };
+    // double[][] polyEff = new double[][] { {
+    // 90.0, 91.0, 89.0, 88.0 }, { 90.0, 91.0, 89.0, 88.0 }, { 90.0, 91.0, 89.0,
+    // 88.1 }, { 90.0, 91.0, 89.0, 88.1 } };
+
+    double[] speed = new double[] {12913, 12298, 11683, 11098, 10453, 9224, 8609, 8200};
+    double[][] flow = new double[][] {
+        {2789.1285, 3174.0375, 3689.2288, 4179.4503, 4570.2768, 4954.7728, 5246.0329, 5661.0331},
+        {2571.1753, 2943.7254, 3440.2675, 3837.4448, 4253.0898, 4668.6643, 4997.1926, 5387.4952},
+        {2415.3793, 2763.0706, 3141.7095, 3594.7436, 4047.6467, 4494.1889, 4853.7353, 5138.7858},
+        {2247.2043, 2799.7342, 3178.3428, 3656.1551, 4102.778, 4394.1591, 4648.3224, 4840.4998},
+        {2072.8397, 2463.9483, 2836.4078, 3202.5266, 3599.6333, 3978.0203, 4257.0022, 4517.345},
+        {1835.9552, 2208.455, 2618.1322, 2940.8034, 3244.7852, 3530.1279, 3753.3738, 3895.9746},
+        {1711.3386, 1965.8848, 2356.9431, 2685.9247, 3008.5154, 3337.2855, 3591.5092},
+        {1636.5807, 2002.8708, 2338.0319, 2642.1245, 2896.4894, 3113.6264, 3274.8764, 3411.2977}};
+    double[][] head =
+        new double[][] {{80.0375, 78.8934, 76.2142, 71.8678, 67.0062, 60.6061, 53.0499, 39.728},
+            {72.2122, 71.8369, 68.9009, 65.8341, 60.7167, 54.702, 47.2749, 35.7471},
+            {65.1576, 64.5253, 62.6118, 59.1619, 54.0455, 47.0059, 39.195, 31.6387},
+            {58.6154, 56.9627, 54.6647, 50.4462, 44.4322, 38.4144, 32.9084, 28.8109},
+            {52.3295, 51.0573, 49.5283, 46.3326, 42.3685, 37.2502, 31.4884, 25.598},
+            {40.6578, 39.6416, 37.6008, 34.6603, 30.9503, 27.1116, 23.2713, 20.4546},
+            {35.2705, 34.6359, 32.7228, 31.0645, 27.0985, 22.7482, 18.0113},
+            {32.192, 31.1756, 29.1329, 26.833, 23.8909, 21.3324, 18.7726, 16.3403},};
+    double[][] efficiency = new double[][] {
+        {77.2452238409573, 79.4154186459363, 80.737960012489, 80.5229826589649, 79.2210931638144,
+            75.4719133864634, 69.6034181197298, 58.7322388482707},
+        {77.0107837113504, 79.3069974136389, 80.8941189021135, 80.7190194665918, 79.5313242980328,
+            75.5912622896367, 69.6846136362097, 60.0043057990909},
+        {77.0043065299874, 79.1690958847856, 80.8038169975675, 80.6543975614197, 78.8532389102705,
+            73.6664774270613, 66.2735600426727, 57.671664571658},
+        {77.0716623789093, 80.4629750233093, 81.1390811169072, 79.6374242667478, 75.380928428817,
+            69.5332969549779, 63.7997587622339, 58.8120614497758},
+        {76.9705872525642, 79.8335492585324, 80.9468133671171, 80.5806471927835, 78.0462158225426,
+            73.0403707523258, 66.5572286338589, 59.8624822515064},
+        {77.5063036680357, 80.2056198362559, 81.0339108025933, 79.6085962687939, 76.3814534404405,
+            70.8027503005902, 64.6437367160571, 60.5299349982342},
+        {77.8175271586685, 80.065165942218, 81.0631362122632, 79.8955051771299, 76.1983240929369,
+            69.289982774309, 60.8567149372229},
+        {78.0924334304045, 80.9353551568667, 80.7904437766234, 78.8639325223295, 75.2170936751143,
+            70.3105081673411, 65.5507568533569, 61.0391468300337}};
+
+    pump1.getPumpChart().setCurves(chartConditions, speed, flow, head, efficiency);
+    pump1.getPumpChart().setHeadUnit("kJ/kg");
+
+    neqsim.processSimulation.processSystem.ProcessSystem operations =
+        new neqsim.processSimulation.processSystem.ProcessSystem();
+    operations.add(stream_1);
+    operations.add(pump1);
+    operations.run();
+
+    System.out.println("pump power " + pump1.getPower());
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public boolean isUsePumpChart() {
+    return usePumpChart;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void setUsePumpChart(boolean usePumpChart) {
+    this.usePumpChart = usePumpChart;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public String getHeadUnit() {
+    return headUnit;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void setHeadUnit(String headUnit) {
+    this.headUnit = headUnit;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public boolean useRealKappa() {
+    return useRealKappa;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void setUseRealKappa(boolean useRealKappa) {
+    this.useRealKappa = useRealKappa;
+  }
+
+  /** {@inheritDoc} */
+  @Override
+  public void plot() {
+    neqsim.dataPresentation.JFreeChart.graph2b graph =
+        new neqsim.dataPresentation.JFreeChart.graph2b(flow, head,
+            Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new), "head vs flow",
+            "flow", "head");
+    graph.setVisible(true);
+    neqsim.dataPresentation.JFreeChart.graph2b graph2 =
+        new neqsim.dataPresentation.JFreeChart.graph2b(flow, efficiency,
+            Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new), "eff vs flow",
+            "flow", "eff");
+    graph2.setVisible(true);
+    neqsim.dataPresentation.JFreeChart.graph2b graph3 =
+        new neqsim.dataPresentation.JFreeChart.graph2b(redflow, redhead,
+            Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
+            "red head vs red flow", "red flow", "red head");
+    graph3.setVisible(true);
+    neqsim.dataPresentation.JFreeChart.graph2b graph4 =
+        new neqsim.dataPresentation.JFreeChart.graph2b(redflow, efficiency,
+            Arrays.stream(speed).mapToObj(String::valueOf).toArray(String[]::new),
+            "red eff vs red dflow", "red flow", "red eff");
+    graph4.setVisible(true);
+  }
 }
diff --git a/src/main/java/neqsim/thermo/system/SystemInterface.java b/src/main/java/neqsim/thermo/system/SystemInterface.java
index 19f07b59b0..3893a7613d 100644
--- a/src/main/java/neqsim/thermo/system/SystemInterface.java
+++ b/src/main/java/neqsim/thermo/system/SystemInterface.java
@@ -2530,7 +2530,7 @@ public void addCharacterized(String[] charNames, double[] charFlowrate, double[]
       double[] relativedensity);
 
   /**
-   * Get normal liquid density of fluid.
+   * Get ideal liquid density of fluid in given unit.
    *
    * @param unit {@link java.lang.String} Supported units are kg/m3 and gr/cm3
    * @return a double
diff --git a/src/main/java/neqsim/thermo/system/SystemThermo.java b/src/main/java/neqsim/thermo/system/SystemThermo.java
index a86c71e1ee..48d7570907 100644
--- a/src/main/java/neqsim/thermo/system/SystemThermo.java
+++ b/src/main/java/neqsim/thermo/system/SystemThermo.java
@@ -66,8 +66,7 @@ abstract class SystemThermo implements SystemInterface {
   protected double criticalPressure = 0;
   private double totalNumberOfMoles = 0;
   public String componentNameTag = "";
-  protected neqsim.thermo.characterization.WaxCharacterise waxCharacterisation = null; // new
-                                                                                       // WaxCharacterise(this);
+  protected neqsim.thermo.characterization.WaxCharacterise waxCharacterisation = null;
   protected double[] beta = new double[6];
   protected int a;
 
@@ -3091,7 +3090,9 @@ public double getMass(String unit) {
   /**
    * {@inheritDoc}
    *
+   * <p>
    * need to call initPhysicalProperties() before this method is called
+   * </p>
    */
   @Override
   public double getCorrectedVolume() {
@@ -5094,8 +5095,10 @@ public SystemProperties getProperties() {
 
 
   /**
-   * @param molefractions
-   * @param type
+   * Wrapper function for addComponent to set fluid type and specify mole fractions.
+   *
+   * @param molefractions Component mole fraction of each component.
+   * @param type Type of fluid. Supports "PlusFluid", "Plus" and default.
    */
   private void setMolarFractions(double[] molefractions, String type) {
     double totalFlow = getTotalNumberOfMoles();
@@ -5226,11 +5229,7 @@ public void addOilFractions(String[] charNames, double[] charFlowrate, double[]
   }
 
 
-  /**
-   * {@inheritDoc}
-   *
-   * Return normal liquid density of fluid in given unit.
-   */
+  /** {@inheritDoc} */
   public double getIdealLiquidDensity(String unit) {
     double normalLiquidDensity = 0.0;
     double molarMass = getMolarMass();