AD: adding PsiBwd/Fwd with doc changes

docs/source/user/aerodyn/examples/ad_primary_example.dat

@@ -34,8 +34,10 @@ True          TIDrag             - Include the drag term in the tangential-induc
         100   MaxIter            - Maximum number of iteration steps (-) [unused when WakeMod=0]
 --- Shear correction 
 False         SectAvg           - Use sector averaging (flag)
-1             SectAvgWeighting  - Weighting function for sector average  {1=Uniform}  within a sector centered on the blade (switch) [used only when SectAvg=True] 
-5             SectAvgNPoints    - Number of points per sectors (-) [used only when SectAvg=True] 
+1             SectAvgWeighting  - Weighting function for sector average  {1=Uniform, default=1}  within a sector centered on the blade (switch) [used only when SectAvg=True] 
+5             SectAvgNPoints    - Number of points per sectors (-) {default=5} [used only when SectAvg=True] 
+-60           SectAvgPsiBwd     - Backward azimuth relative to blade where the sector starts (<=0) {default=-60} (deg) [used only when SectAvg=True]
+ 60           SectAvgPsiFwd     - Forward azimuth relative to blade where the sector ends (>=0) {default=60} (deg) [used only when SectAvg=True]
 --- Dynamic wake/inflow
           2   DBEMT_Mod          - Type of dynamic BEMT (DBEMT) model {0=No Dynamic Wake, -1=Frozen Wake for linearization, 1:constant tau1, 2=time-dependent tau1, 3=constant tau1 with continuous formulation} (-)
          20   tau1_const         - Time constant for DBEMT (s) [used only when DBEMT_Mod=1 or 3]

docs/source/user/aerodyn/input.rst

@@ -197,6 +197,8 @@ The following inputs in this section are only used when ``WakeMod = 1``.
 - ``Skew_Mod=0`` means no skew model at all (not recommended) 
 - ``Skew_Mod=-1`` throws away non-normal component (for linearization). This setting makes sure the wind speed is always normal to the rotor to limit periodic variation of the wind speed if the rotor is not perpendicular to the wind (e.g. tower top tilting or tilt). This is mostly needed for linearization. 
 
+Currently (``Skew_Mod=0``) or (``Skew_Mod=1`` and ``SkewModCorr=False`` and ``SkewRedistr_Mod = 0``)  are the same, both set of inputs turn off the skew correction entirely.
+
 .. note::
     Link to old inputs: Previous implementations always had the skew model on. `Skew_Mod=-1` replaces the old `SkewMod=0` (an option that few users were using). 
 
@@ -253,16 +255,22 @@ Shear corrections
 ~~~~~~~~~~~~~~~~~
 
 The BEM algorithm may need to be corrected to account for shear.
-Currently, a sector average correction is implemented, as a beta feature, to limit fluctuations associtated with variations of wind speed as the blade rotates.
+Currently, a sector average correction is implemented, as a beta feature, to limit fluctuations associated with variations of wind speed as the blade rotates.
 
-The feature will be documented at a later time.
+The feature will be documented at a later time and is still at an experimental stage.
 
-**SectAvg**  Use Sector Averaging (flag)
+**SectAvg**  Use Sector Averaging (flag).
+The method uses sectors expanding forward and backward relative to the current azimuth of the blade (see ``SectAvgPsiBwd`` and ``SectAvgPsiFwd``). 
+The velocity is averaged within this sector by attributing different weighting at different points in the sector (see ``SectAvgWeighting``).
 
 **SectAvgWeighting** Weighting function for sector average. 
-1=Uniform  within a sector centered on the blade (switch) [used only when ``SectAvg=True``] 
+1=Uniform  (switch) [used only when ``SectAvg=True``]. Default is 1.
+
+**SectAvgNPoints** Number of points per sectors (-) [used only when ``SectAvg=True``]. Default is 5.
+
+**SectAvgPsiBwd** Backward azimuth (in degrees) relative to the blade azimuth where the sector starts. Must be negative. [used only when SectAvg=True]. Default is -60 deg.
 
-**SectAvgNPoints** Number of points per sectors (-) [used only when ``SectAvg=True``] 
+**SectAvgPsiFwd** Forward azimuth (in degrees) relative to the blade azimuth where the sector ends. Must be positive. [used only when SectAvg=True]. Default is 60 deg.
 
 
 

modules/aerodyn/src/AeroDyn_IO.f90

@@ -852,8 +852,10 @@ SUBROUTINE ParsePrimaryFileInfo( PriPath, InitInp, InputFile, RootName, NumBlade
       call WrScr('         Setting SectAvg to False as the input is Missing (legacy behavior).')
       InputFileData%SectAvg = .false.
    else
-      call ParseVar( FileInfo_In, CurLine, "SectAvgWeighting", InputFileData%SA_Weighting, ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
-      call ParseVar( FileInfo_In, CurLine, "SectAvgNPoints"  , InputFileData%SA_nPerSec, ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
+      call ParseVarWDefault( FileInfo_In, CurLine, "SectAvgWeighting", InputFileData%SA_Weighting, 1      , ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
+      call ParseVarWDefault( FileInfo_In, CurLine, "SectAvgNPoints"  , InputFileData%SA_nPerSec,   5      , ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
+      call ParseVarWDefault( FileInfo_In, CurLine, "SectAvgPsiBwd"   , InputFileData%SA_PsiBwd,  -60._ReKi, ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
+      call ParseVarWDefault( FileInfo_In, CurLine, "SectAvgPsiFwd"   , InputFileData%SA_PsiFwd,   60._ReKi, ErrStat2, ErrMsg2, UnEc ); if (Failed()) return
       call ParseCom (FileInfo_in, CurLine, sDummy, errStat2, errMsg2, UnEc, isLegalComment); if (Failed()) return
    endif
 

modules/aerodyn/src/AeroDyn_Registry.txt

@@ -199,7 +199,7 @@ typedef	^	AD_InputFile	Logical	SectAvg	-	-	False	"Use Sector average for BEM inf
 typedef	^	     ^      	IntKi  	SA_Weighting	-	-	1	    "Sector Average - Weighting function for sector average  {1=Uniform, 2=Impulse, }  within a 360/nB sector centered on the blade (switch) [used only when SectAvg=True]" -
 typedef	^	     ^      	ReKi   	SA_PsiBwd	-	-60	-	"Sector Average - Backard Azimuth (<0)"	deg
 typedef	^	     ^      	ReKi   	SA_PsiFwd	-	 60	-	"Sector Average - Forward Azimuth (>0)"	deg
-typedef	^	     ^      	IntKi  	SA_nPerSec	-	 11	-	"Sector average - Number of points per sectors (-) [used only when SectAvg=True]" -
+typedef	^	     ^      	IntKi  	SA_nPerSec	-	  5	-	"Sector average - Number of points per sectors (-) [used only when SectAvg=True]" -
 typedef	^	     ^      	LOGICAL	AoA34	-	-	-	"Sample the angle of attack (AoA) at the 3/4 chord or the AC point {default=True} [always used]"	-
 typedef	^	     ^      	IntKi	UAMod	-	-	-	"Unsteady Aero Model Switch (switch) {0=Quasi-steady (no UA),  2=Gonzalez's variant (changes in Cn,Cc,Cm), 3=Minnema/Pierce variant (changes in Cc and Cm)}" -
 typedef	^	AD_InputFile	LOGICAL	FLookup	-	-	-	"Flag to indicate whether a lookup for f' will be calculated (TRUE) or whether best-fit exponential equations will be used (FALSE); if FALSE S1-S4 must be provided in airfoil input files [used only when AFAeroMod=2]"	flag

modules/aerodyn/src/AeroDyn_Types.f90

@@ -225,7 +225,7 @@ MODULE AeroDyn_Types
     INTEGER(IntKi)  :: SA_Weighting = 0_IntKi      !< Sector Average - Weighting function for sector average  {1=Uniform, 2=Impulse, }  within a 360/nB sector centered on the blade (switch) [used only when SectAvg=True] [-]
     REAL(ReKi)  :: SA_PsiBwd = -60      !< Sector Average - Backard Azimuth (<0) [deg]
     REAL(ReKi)  :: SA_PsiFwd = 60      !< Sector Average - Forward Azimuth (>0) [deg]
-    INTEGER(IntKi)  :: SA_nPerSec = 11      !< Sector average - Number of points per sectors (-) [used only when SectAvg=True] [-]
+    INTEGER(IntKi)  :: SA_nPerSec = 5      !< Sector average - Number of points per sectors (-) [used only when SectAvg=True] [-]
     LOGICAL  :: AoA34 = .false.      !< Sample the angle of attack (AoA) at the 3/4 chord or the AC point {default=True} [always used] [-]
     INTEGER(IntKi)  :: UAMod = 0_IntKi      !< Unsteady Aero Model Switch (switch) {0=Quasi-steady (no UA),  2=Gonzalez's variant (changes in Cn,Cc,Cm), 3=Minnema/Pierce variant (changes in Cc and Cm)} [-]
     LOGICAL  :: FLookup = .false.      !< Flag to indicate whether a lookup for f' will be calculated (TRUE) or whether best-fit exponential equations will be used (FALSE); if FALSE S1-S4 must be provided in airfoil input files [used only when AFAeroMod=2] [flag]