Fix view factor aggregation.

NREL · Aug 6, 2021 · f8b05c7 · f8b05c7
1 parent 7677a1c
commit f8b05c7
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Showing 2 changed files with 60 additions and 24 deletions.
diff --git a/src/EnergyPlus/DataViewFactorInformation.hh b/src/EnergyPlus/DataViewFactorInformation.hh
@@ -68,7 +68,7 @@ namespace DataViewFactorInformation {
         std::vector<std::string> ZoneNames; // Zone names which are part of this enclosure
         std::vector<int> ZoneNums;          // Zones which are part of this enclosure
         int NumOfSurfaces;                  // Number of surfaces in the enclosure
-        Array2D<Real64> F;                  // View Factors
+        Array2D<Real64> F;                  // View Factors: F(i,j) = from surface j to surface i (counter-intuitive, but optimized for performance)
         Array2D<Real64> ScriptF;            // Hottel's Script F //Tuned Transposed
         Array1D<Real64> Area;               // Surface area
         Array1D<Real64> Emissivity;         // Surface emissivity

diff --git a/src/EnergyPlus/HeatBalanceIntRadExchange.cc b/src/EnergyPlus/HeatBalanceIntRadExchange.cc
@@ -1329,34 +1329,70 @@ namespace HeatBalanceIntRadExchange {
                                                                      state.dataIPShortCut->cAlphaFieldNames,
                                                                      state.dataIPShortCut->cNumericFieldNames);
 
-            if (NumNums < pow_2(N)) {
-                ShowWarningError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", not enough values.");
-                ShowContinueError(
-                    state,
-                    format("...Number of input values [{}] is less than the required number=[{}] Missing surface pairs will have a zero view factor.",
-                           NumNums,
-                           pow_2(N)));
-            }
             F = 0.0;
             numinx1 = 0;
+            if (!state.dataSurface->UseRepresentativeSurfaceCalculations) {
+                if (NumNums < pow_2(N)) {
+                    ShowWarningError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", not enough values.");
+                    ShowContinueError(
+                        state,
+                        format("...Number of input values [{}] is less than the required number=[{}] Missing surface pairs will have a zero view factor.",
+                               NumNums,
+                               pow_2(N)));
+                }
 
-            // TODO: Automatic Window Multipliers, throw error if view factors aren't the same for representative surfaces
-            for (index = 2; index <= NumAlphas; index += 2) {
-                inx1 = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index), enclosureSurfaceNames, N);
-                inx2 = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index + 1), enclosureSurfaceNames, N);
-                if (inx1 == 0) {
-                    ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
-                    ShowContinueError(state, "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index) + "\", not in this zone or enclosure.");
-                    ErrorsFound = true;
+                for (index = 2; index <= NumAlphas; index += 2) {
+                    inx1 = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index), enclosureSurfaceNames, N);
+                    inx2 = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index + 1), enclosureSurfaceNames, N);
+                    if (inx1 == 0) {
+                        ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
+                        ShowContinueError(state, "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index) + "\", not in this zone or enclosure.");
+                        ErrorsFound = true;
+                    }
+                    if (inx2 == 0) {
+                        ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
+                        ShowContinueError(state,
+                                          "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index + 2) + "\", not in this zone or enclosure.");
+                        ErrorsFound = true;
+                    }
+                    ++numinx1;
+                    if (inx1 > 0 && inx2 > 0) F(inx2, inx1) = state.dataIPShortCut->rNumericArgs(numinx1);
                 }
-                if (inx2 == 0) {
-                    ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
-                    ShowContinueError(state,
-                                      "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index + 2) + "\", not in this zone or enclosure.");
-                    ErrorsFound = true;
+            } else {
+
+                // Aggregate view factors for representative surfaces
+                for (index = 2; index <= NumAlphas; index += 2) {
+                    int fromSurfNum = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index), state.dataSurface->Surface, N);
+                    int toSurfNum = UtilityRoutines::FindItemInList(state.dataIPShortCut->cAlphaArgs(index + 1), state.dataSurface->Surface, N);
+                    if (fromSurfNum == 0) {
+                        ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
+                        ShowContinueError(state, "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index) + "\", not in this zone or enclosure.");
+                        ErrorsFound = true;
+                    }
+                    if (toSurfNum == 0) {
+                        ShowSevereError(state, "GetInputViewFactors: " + cCurrentModuleObject + "=\"" + EnclosureName + "\", invalid surface name.");
+                        ShowContinueError(state,
+                                          "...Surface name=\"" + state.dataIPShortCut->cAlphaArgs(index + 2) + "\", not in this zone or enclosure.");
+                        ErrorsFound = true;
+                    }
+                    ++numinx1;
+                    if (fromSurfNum > 0 && toSurfNum > 0) {
+                        auto &fromSurf = state.dataSurface->Surface(fromSurfNum);
+                        auto &toSurf = state.dataSurface->Surface(toSurfNum);
+                        int repFromSurfNum = fromSurf.RepresentativeCalcSurfNum;
+                        int repToSurfNum = toSurf.RepresentativeCalcSurfNum;
+                        // "From" surfaces within a representative group should all have the same view factors to the other surfaces
+                        // "To" surfaces within a representative group should aggregate the view factors from other surfaces
+                        if (fromSurfNum == repFromSurfNum) {
+                            auto &repFromSurf = state.dataSurface->Surface(repFromSurfNum);
+                            auto &repToSurf = state.dataSurface->Surface(repToSurfNum);
+                            int fromInx = UtilityRoutines::FindItemInList(repFromSurf.Name, enclosureSurfaceNames, N);
+                            int toInx = UtilityRoutines::FindItemInList(repToSurf.Name, enclosureSurfaceNames, N);
+                            F(toInx, fromInx) += state.dataIPShortCut->rNumericArgs(numinx1);
+                        }
+                        // TODO: Track view factors to ensure that "From" surfaces have similar view factors?
+                    }
                 }
-                ++numinx1;
-                if (inx1 > 0 && inx2 > 0) F(inx2, inx1) = state.dataIPShortCut->rNumericArgs(numinx1);
             }
             enclosureSurfaceNames.deallocate();
         }