From 4b90566a773dcaae88769c8d467dbcbad95d33a8 Mon Sep 17 00:00:00 2001
From: Florian Schueltke <florian.schueltke@ilr.rwth-aachen.de>
Date: Wed, 19 Feb 2025 18:17:58 +0100
Subject: [PATCH 1/3] aerodynamic_analysis (schueltke): - corrected wave drag
calibration - corrected function call of neutral point estimation with
correct trimmed polar
---
.../src/bwb/bwbDefaultStrategy.cpp | 21 ++++++++-
.../src/methods/waveDragMason.cpp | 5 +--
.../src/methods/waveDragMason.h | 3 +-
.../src/taw/tawDefaultStrategy.cpp | 43 ++++++++++++-------
4 files changed, 50 insertions(+), 22 deletions(-)
diff --git a/aerodynamic_analysis/src/bwb/bwbDefaultStrategy.cpp b/aerodynamic_analysis/src/bwb/bwbDefaultStrategy.cpp
index c6fd74b4..3255e85e 100644
--- a/aerodynamic_analysis/src/bwb/bwbDefaultStrategy.cpp
+++ b/aerodynamic_analysis/src/bwb/bwbDefaultStrategy.cpp
@@ -227,7 +227,26 @@ void bwbDefaultStrategy::calculateWaveDragMason(waveDragMason *myWaveDragMason)
= myWaveDragMason->calculateWaveDrag(currentPolarSet.cleanPolars.at(polarID).Points.at(pointID),
currentPolarSet.cleanPolars.at(polarID).MachNumber,
0, 0, currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).yStations,
- currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).Cl_distr, true);
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).Cl_distr);
+ }
+ //calibration of wing wave drag if calibration is active
+ if (myWaveDragMason->doWaveDragMasonCalibration && currentPolarSet.cleanPolars.at(polarID).PointsWing.back().CD_wave > 0) { // check if polar has wave drag
+ for (size_t pointID(0); pointID < currentPolarSet.cleanPolars.at(polarID).Points.size(); ++pointID) {
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave += myWaveDragMason->calculateWaveDragCorrectionByCalibration(
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave, currentPolarSet.cleanPolars.at(polarID).Points.at(pointID),
+ currentPolarSet.cleanPolars.at(polarID).MachNumber);
+ }
+ }
+ //correction of wing wave drag and summation to total drag
+ for (size_t pointID(0); pointID < currentPolarSet.cleanPolars.at(polarID).Points.size(); ++pointID) {
+ //wing
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave +=
+ myWaveDragMason->calculateWaveDragCorrectionByDragCounts(myWaveDragMason->waveDragCtCorrForCalibrationWing);
+ //check negative wave drag due to correction
+ if (currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave < 0.) { // Check if wing wave drag is negative due to calibration; if so, set to zero
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave = 0.;
+ }
+ //calculate total wave drag
currentPolarSet.cleanPolars.at(polarID).Points.at(pointID).CD_wave = currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave;
}
}
diff --git a/aerodynamic_analysis/src/methods/waveDragMason.cpp b/aerodynamic_analysis/src/methods/waveDragMason.cpp
index 87f264ab..51a24ddd 100644
--- a/aerodynamic_analysis/src/methods/waveDragMason.cpp
+++ b/aerodynamic_analysis/src/methods/waveDragMason.cpp
@@ -97,7 +97,7 @@ waveDragMason::waveDragMason(const std::shared_ptr<RuntimeIO>& rtIO, const waveD
}
double waveDragMason::calculateWaveDrag(const PolarPoint& aPolarPoint, const double aMachNumber, size_t liftingSurfaceIndex, const double chordWiseSweepPosition,
- const std::vector<double>& spanStations, const std::vector<double>& Cl_distribution, const bool doCorrection) {
+ const std::vector<double>& spanStations, const std::vector<double>& Cl_distribution) {
// consistency check
if (spanStations.size() != Cl_distribution.size()) {
stringstream errorMessage;
@@ -174,9 +174,6 @@ double waveDragMason::calculateWaveDrag(const PolarPoint& aPolarPoint, const dou
}
// double the drag to account for the whole wing
C_DWaveTotal = 2. * std::accumulate(C_DWaveSegment.begin(), C_DWaveSegment.end(), 0.0) / liftingSurfaceRefArea;
- if (doCorrection) {
- C_DWaveTotal += calculateWaveDragCorrectionByCalibration(C_DWaveTotal, aPolarPoint, aMachNumber);
- }
return C_DWaveTotal;
}
diff --git a/aerodynamic_analysis/src/methods/waveDragMason.h b/aerodynamic_analysis/src/methods/waveDragMason.h
index c2b6ef99..72870dbd 100644
--- a/aerodynamic_analysis/src/methods/waveDragMason.h
+++ b/aerodynamic_analysis/src/methods/waveDragMason.h
@@ -72,10 +72,9 @@ class waveDragMason{
* \param liftingSurfaceIndex the index of the lifting surface, which gets calculated
* \param spanStations vector of span coordinates of the wing corresponding to the lift points
* \param Cl_distribution vector of lift coefficients corresponding to the span station coordinates
- * \param doCorrection switch do enable CL based calibraiton
*/
double calculateWaveDrag(const PolarPoint& aPolarPoint, const double machNumber, size_t liftingSurfaceIndex, const double chordWiseSweepPosition,
- const std::vector<double>& spanStations, const std::vector<double>& Cl_distribution, const bool doCorrection);
+ const std::vector<double>& spanStations, const std::vector<double>& Cl_distribution);
/** \brief Function calculates the wave drag correction for a polar point using a clibration function
* \details this function should only be used for wing and not for stabilizer
* \param waveDragBeforeCorrection the value of the uncorrected wave drag point
diff --git a/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp b/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
index 23532b5a..4da20902 100644
--- a/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
+++ b/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
@@ -390,30 +390,43 @@ void tawDefaultStrategy::calculateWaveDragMason(waveDragMason *myWaveDragMason)
sweepPosition = 0.5;
}
for (size_t pointID(0); pointID < currentPolarSet.cleanPolars.at(polarID).Points.size(); ++pointID) {
- // wave drag wing
+ // wave drag wing (uncorrected; correction will be applied afterwards)
currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave
= myWaveDragMason->calculateWaveDrag(currentPolarSet.cleanPolars.at(polarID).Points.at(pointID),
currentPolarSet.cleanPolars.at(polarID).MachNumber,
0, sweepPosition, currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).yStations,
- currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).Cl_distr,
- myWaveDragMason->doWaveDragMasonCalibration)
- + myWaveDragMason->calculateWaveDragCorrectionByDragCounts(myWaveDragMason->waveDragCtCorrForCalibrationWing);
- if (currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave < 0.) { // Check if drag is negative due to calibration; if so, set to zero
- currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave = 0.;
- }
- // wave drag stabilizer
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).Cl_distr);
+ // wave drag stabilizer (uncorrected; no calibration needed/assumed for stabilizer)
currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave
= myWaveDragMason->calculateWaveDrag(currentPolarSet.cleanPolars.at(polarID).Points.at(pointID),
currentPolarSet.cleanPolars.at(polarID).MachNumber,
1, sweepPosition, currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).yStations,
- currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).Cl_distr,
- false)
- + myWaveDragMason->calculateWaveDragCorrectionByDragCounts(myWaveDragMason->waveDragCtCorrForCalibrationStabilizer);
- if (currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave < 0.) { // Check if drag is negative due to calibration; if so, set to zero
+ currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).Cl_distr);
+ }
+ //calibration of wing wave drag if calibration is active
+ if (myWaveDragMason->doWaveDragMasonCalibration && currentPolarSet.cleanPolars.at(polarID).PointsWing.back().CD_wave > 0) { // check if polar has wave drag
+ for (size_t pointID(0); pointID < currentPolarSet.cleanPolars.at(polarID).Points.size(); ++pointID) {
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave += myWaveDragMason->calculateWaveDragCorrectionByCalibration(
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave, currentPolarSet.cleanPolars.at(polarID).Points.at(pointID),
+ currentPolarSet.cleanPolars.at(polarID).MachNumber);
+ }
+ }
+ //correction of wing and stabilizer wave drag and summation to total drag
+ for (size_t pointID(0); pointID < currentPolarSet.cleanPolars.at(polarID).Points.size(); ++pointID) {
+ //wing
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave +=
+ myWaveDragMason->calculateWaveDragCorrectionByDragCounts(myWaveDragMason->waveDragCtCorrForCalibrationWing);
+ //stabilizer
+ currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave +=
+ myWaveDragMason->calculateWaveDragCorrectionByDragCounts(myWaveDragMason->waveDragCtCorrForCalibrationStabilizer);
+ //check negative wave drag due to correction
+ if (currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave < 0.) { // Check if wing wave drag is negative due to calibration; if so, set to zero
+ currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave = 0.;
+ }
+ if (currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave < 0.) { // Check if stabilizer wave drag is negative due to calibration; if so, set to zero
currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave = 0.;
}
-
- // total wave drag
+ //calculate total wave drag
currentPolarSet.cleanPolars.at(polarID).Points.at(pointID).CD_wave = currentPolarSet.cleanPolars.at(polarID).PointsWing.at(pointID).CD_wave
+ currentPolarSet.cleanPolars.at(polarID).PointsStab.at(pointID).CD_wave;
}
@@ -983,7 +996,7 @@ void tawDefaultStrategy::setReferenceValues() {
data_->span.set_value(geom2::measure::span(liftingSurfaces.at(0)));
data_->MAC.set_value(geom2::measure::mean_aerodynamic_chord(liftingSurfaces.at(0)));
data_->S_ref.set_value(geom2::measure::reference_area(liftingSurfaces.at(0)));
- data_->neutral_point_xCoordinate.set_value(getNeutralPointXposition(getTrimmedCruisePolar(polarDataCGMap.at(0).at(0).cleanPolars, data_->initialCruiseMachNumber),
+ data_->neutral_point_xCoordinate.set_value(getNeutralPointXposition(getTrimmedCruisePolar(polarDataTrimMap.at(0).cleanPolars, data_->initialCruiseMachNumber),
data_->MAC.value(), CoGPositions["design"].xCoordinate));
}
--
GitLab
From b29d4178544a7aa341d65330302f6850109eea55 Mon Sep 17 00:00:00 2001
From: Florian Schueltke <florian.schueltke@ilr.rwth-aachen.de>
Date: Wed, 19 Feb 2025 20:25:39 +0100
Subject: [PATCH 2/3] aerodynamic_analysis (schueltke): - updated
calculateWaveDragCorrectionByCalibration function; output should not change,
only clean up
---
aerodynamic_analysis/src/methods/waveDragMason.cpp | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/aerodynamic_analysis/src/methods/waveDragMason.cpp b/aerodynamic_analysis/src/methods/waveDragMason.cpp
index 51a24ddd..82e1c672 100644
--- a/aerodynamic_analysis/src/methods/waveDragMason.cpp
+++ b/aerodynamic_analysis/src/methods/waveDragMason.cpp
@@ -178,15 +178,10 @@ double waveDragMason::calculateWaveDrag(const PolarPoint& aPolarPoint, const dou
}
double waveDragMason::calculateWaveDragCorrectionByCalibration(const double& waveDragBeforeCorrection, const PolarPoint& aPolarPoint, const double& aMachNumber) {
- double totalWaveDragCorrection(0.);
/* Drag calibration. First introduced in commit [4eab519c2] based on experimental data in [Lam2010], 23.06.2010. After several changes,
the current definition and values in config are from Risse, commit [2ec91580] on 02.08.2015. Especially for wave drag calibration, the values should be used
carefully, as they usually only fit to one specific airfoil family and, thus, k-factor. */
- totalWaveDragCorrection = CLFact * pow(aMachNumber * aPolarPoint.CL, CLExp);
- if (aMachNumber >= 0.5) {
- totalWaveDragCorrection = CLFact * pow(aMachNumber * aPolarPoint.CL, CLExp);
- }
- return totalWaveDragCorrection;
+ return CLFact * pow(aMachNumber * aPolarPoint.CL, CLExp);
}
double waveDragMason::calculateWaveDragCorrectionByDragCounts(const double& waveDragCtCorrForCalibration) {
--
GitLab
From e485dfa443c74d5033e6c59bfa83d61e4c64be66 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20Sch=C3=BCltke?=
<florian.schueltke@ilr.rwth-aachen.de>
Date: Thu, 20 Feb 2025 15:22:09 +0100
Subject: [PATCH 3/3] reverted change as discussed --> to be clarified for
final release
---
aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp b/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
index 4da20902..91708daf 100644
--- a/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
+++ b/aerodynamic_analysis/src/taw/tawDefaultStrategy.cpp
@@ -996,7 +996,7 @@ void tawDefaultStrategy::setReferenceValues() {
data_->span.set_value(geom2::measure::span(liftingSurfaces.at(0)));
data_->MAC.set_value(geom2::measure::mean_aerodynamic_chord(liftingSurfaces.at(0)));
data_->S_ref.set_value(geom2::measure::reference_area(liftingSurfaces.at(0)));
- data_->neutral_point_xCoordinate.set_value(getNeutralPointXposition(getTrimmedCruisePolar(polarDataTrimMap.at(0).cleanPolars, data_->initialCruiseMachNumber),
+ data_->neutral_point_xCoordinate.set_value(getNeutralPointXposition(getTrimmedCruisePolar(polarDataCGMap.at(0).at(0).cleanPolars, data_->initialCruiseMachNumber),
data_->MAC.value(), CoGPositions["design"].xCoordinate));
}
--
GitLab