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Merge pull request #1288 from openrocket/revert-1273-normalize-CD-names

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Revert "Refer to drag coefficient consistently as CD"
This commit is contained in:
Joe Pfeiffer 2022-04-10 09:41:35 -06:00 committed by GitHub
commit 507dbb7c36
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GPG Key ID: 4AEE18F83AFDEB23
9 changed files with 61 additions and 57 deletions
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22
core/src/net/sf/openrocket/aerodynamics/AerodynamicForces.java
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@ -51,7 +51,7 @@ public class AerodynamicForces implements Cloneable, Monitorable {
/** Axial drag coefficient, CA */
private double CDaxial = Double.NaN;
private double Caxial = Double.NaN;
/** Total drag force coefficient, parallel to the airflow. */
private double CD = Double.NaN;
@ -181,13 +181,13 @@ public class AerodynamicForces implements Cloneable, Monitorable {
return CrollForce;
}
public void setCDaxial(double cdaxial) {
CDaxial = cdaxial;
public void setCaxial(double caxial) {
Caxial = caxial;
modID++;
}
public double getCDaxial() {
return CDaxial;
public double getCaxial() {
return Caxial;
}
public void setCD(double cD) {
@ -277,7 +277,7 @@ public class AerodynamicForces implements Cloneable, Monitorable {
setCroll(Double.NaN);
setCrollDamp(Double.NaN);
setCrollForce(Double.NaN);
setCDaxial(Double.NaN);
setCaxial(Double.NaN);
setCD(Double.NaN);
setPitchDampingMoment(Double.NaN);
setYawDampingMoment(Double.NaN);
@ -299,7 +299,7 @@ public class AerodynamicForces implements Cloneable, Monitorable {
setCroll(0);
setCrollDamp(0);
setCrollForce(0);
setCDaxial(0);
setCaxial(0);
setCD(0);
setPitchDampingMoment(0);
setYawDampingMoment(0);
@ -334,7 +334,7 @@ public class AerodynamicForces implements Cloneable, Monitorable {
MathUtil.equals(this.getCroll(), other.getCroll()) &&
MathUtil.equals(this.getCrollDamp(), other.getCrollDamp()) &&
MathUtil.equals(this.getCrollForce(), other.getCrollForce()) &&
MathUtil.equals(this.getCDaxial(), other.getCDaxial()) &&
MathUtil.equals(this.getCaxial(), other.getCaxial()) &&
MathUtil.equals(this.getCD(), other.getCD()) &&
MathUtil.equals(this.getPressureCD(), other.getPressureCD()) &&
MathUtil.equals(this.getBaseCD(), other.getBaseCD()) &&
@ -346,7 +346,7 @@ public class AerodynamicForces implements Cloneable, Monitorable {
@Override
public int hashCode() {
return (int) (1000*(this.getCD()+this.getCDaxial()+this.getCNa())) + this.getCP().hashCode();
return (int) (1000*(this.getCD()+this.getCaxial()+this.getCNa())) + this.getCP().hashCode();
}
@ -373,8 +373,8 @@ public class AerodynamicForces implements Cloneable, Monitorable {
if (!Double.isNaN(getCroll()))
text += "Croll:" + getCroll() + ",";
if (!Double.isNaN(getCDaxial()))
text += "CDaxial:" + getCDaxial() + ",";
if (!Double.isNaN(getCaxial()))
text += "Caxial:" + getCaxial() + ",";
if (!Double.isNaN(getCD()))
text += "CD:" + getCD() + ",";

38
core/src/net/sf/openrocket/aerodynamics/BarrowmanCalculator.java
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@ -82,11 +82,11 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
// Calculate non-axial force data
calculateForceAnalysis(conditions, configuration.getRocket(), instMap, eachMap, assemblyMap, warnings);
// Calculate drag coefficient data
// Calculate friction data
AerodynamicForces rocketForces = assemblyMap.get(configuration.getRocket());
rocketForces.setFrictionCD(calculateFrictionCD(configuration, conditions, eachMap, warnings));
rocketForces.setPressureCD(calculatePressureCD(configuration, conditions, eachMap, warnings));
rocketForces.setBaseCD(calculateBaseCD(configuration, conditions, eachMap, warnings));
rocketForces.setFrictionCD(calculateFrictionDrag(configuration, conditions, eachMap, warnings));
rocketForces.setPressureCD(calculatePressureDrag(configuration, conditions, eachMap, warnings));
rocketForces.setBaseCD(calculateBaseDrag(configuration, conditions, eachMap, warnings));
Map<RocketComponent, AerodynamicForces> finalMap = new LinkedHashMap<>();
for(final RocketComponent comp : instMap.keySet()){
@ -117,7 +117,7 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
f.setFrictionCD(0);
f.setCD(f.getBaseCD() + f.getPressureCD() + f.getFrictionCD());
f.setCDaxial(calculateAxialCD(conditions, f.getCD()));
f.setCaxial(calculateAxialDrag(conditions, f.getCD()));
finalMap.put(comp, f);
}
@ -177,13 +177,13 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
AerodynamicForces total = calculateNonAxialForces(configuration, conditions, warnings);
// Calculate friction data
total.setFrictionCD(calculateFrictionCD(configuration, conditions, null, warnings));
total.setPressureCD(calculatePressureCD(configuration, conditions, null, warnings));
total.setBaseCD(calculateBaseCD(configuration, conditions, null, warnings));
total.setFrictionCD(calculateFrictionDrag(configuration, conditions, null, warnings));
total.setPressureCD(calculatePressureDrag(configuration, conditions, null, warnings));
total.setBaseCD(calculateBaseDrag(configuration, conditions, null, warnings));
total.setCD(total.getFrictionCD() + total.getPressureCD() + total.getBaseCD());
total.setCDaxial(calculateAxialCD(conditions, total.getCD()));
total.setCaxial(calculateAxialDrag(conditions, total.getCD()));
// Calculate pitch and yaw damping moments
calculateDampingMoments(configuration, conditions, total);
@ -322,7 +322,7 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
* @param set Set to handle
* @return friction drag for entire rocket
*/
private double calculateFrictionCD(FlightConfiguration configuration, FlightConditions conditions,
private double calculateFrictionDrag(FlightConfiguration configuration, FlightConditions conditions,
Map<RocketComponent, AerodynamicForces> map, WarningSet set) {
double c1 = 1.0, c2 = 1.0;
@ -523,7 +523,9 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
if (map != null) {
map.get(c).setFrictionCD(cd / conditions.getRefArea());
}
}
}
}
@ -553,7 +555,7 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
* @param warningSet all current warnings
* @return
*/
private double calculatePressureCD(FlightConfiguration configuration, FlightConditions conditions,
private double calculatePressureDrag(FlightConfiguration configuration, FlightConditions conditions,
Map<RocketComponent, AerodynamicForces> forceMap, WarningSet warningSet) {
double stagnation, base, total;
@ -576,8 +578,8 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
for(InstanceContext context: contextList ) {
// Pressure fore drag
double cd = calcMap.get(c).calculatePressureCD(conditions, stagnation, base,
warningSet);
double cd = calcMap.get(c).calculatePressureDragForce(conditions, stagnation, base,
warningSet);
total += cd;
if (forceMap != null) {
@ -622,8 +624,8 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
* @param warnings all current warnings
* @return
*/
private double calculateBaseCD(FlightConfiguration configuration, FlightConditions conditions,
Map<RocketComponent, AerodynamicForces> map, WarningSet warnings) {
private double calculateBaseDrag(FlightConfiguration configuration, FlightConditions conditions,
Map<RocketComponent, AerodynamicForces> map, WarningSet warnings) {
double base, total;
@ -685,6 +687,8 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
return total;
}
/**
* gets CD by the speed
* @param m Mach number for calculation
@ -735,13 +739,13 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
/**
* Calculate the axial drag coefficient from the total drag coefficient.
* Calculate the axial drag from the total drag coefficient.
*
* @param conditions
* @param cd
* @return
*/
private double calculateAxialCD(FlightConditions conditions, double cd) {
private double calculateAxialDrag(FlightConditions conditions, double cd) {
double aoa = MathUtil.clamp(conditions.getAOA(), 0, Math.PI);
double mul;

24
core/src/net/sf/openrocket/aerodynamics/barrowman/FinSetCalc.java
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@ -623,11 +623,11 @@ public class FinSetCalc extends RocketComponentCalc {
// }
@Override
public double calculatePressureCD(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings) {
public double calculatePressureDragForce(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings) {
double mach = conditions.getMach();
double cd = 0;
double drag = 0;
// Pressure fore-drag
if (crossSection == FinSet.CrossSection.AIRFOIL ||
@ -635,34 +635,34 @@ public class FinSetCalc extends RocketComponentCalc {
// Round leading edge
if (mach < 0.9) {
cd = Math.pow(1 - pow2(mach), -0.417) - 1;
drag = Math.pow(1 - pow2(mach), -0.417) - 1;
} else if (mach < 1) {
cd = 1 - 1.785 * (mach - 0.9);
drag = 1 - 1.785 * (mach - 0.9);
} else {
cd = 1.214 - 0.502 / pow2(mach) + 0.1095 / pow2(pow2(mach));
drag = 1.214 - 0.502 / pow2(mach) + 0.1095 / pow2(pow2(mach));
}
} else if (crossSection == FinSet.CrossSection.SQUARE) {
cd = stagnationCD;
drag = stagnationCD;
} else {
throw new UnsupportedOperationException("Unsupported fin profile: " + crossSection);
}
// Slanted leading edge
cd *= pow2(cosGammaLead);
drag *= pow2(cosGammaLead);
// Trailing edge drag
if (crossSection == FinSet.CrossSection.SQUARE) {
cd += baseCD;
drag += baseCD;
} else if (crossSection == FinSet.CrossSection.ROUNDED) {
cd += baseCD / 2;
drag += baseCD / 2;
}
// Airfoil assumed to have zero base drag
// Scale to correct reference area
cd *= cd * span * thickness / conditions.getRefArea();
drag *= span * thickness / conditions.getRefArea();
return cd;
return drag;
}
private void calculateInterferenceFinCount(FinSet component) {

2
core/src/net/sf/openrocket/aerodynamics/barrowman/LaunchLugCalc.java
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@ -31,7 +31,7 @@ public class LaunchLugCalc extends RocketComponentCalc {
}
@Override
public double calculatePressureCD(FlightConditions conditions,
public double calculatePressureDragForce(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings) {
return CDmul*stagnationCD * refArea / conditions.getRefArea();

2
core/src/net/sf/openrocket/aerodynamics/barrowman/RocketComponentCalc.java
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@ -39,6 +39,6 @@ public abstract class RocketComponentCalc {
* @param warnings set in which to store possible warnings
* @return the pressure drag of the component
*/
public abstract double calculatePressureCD(FlightConditions conditions,
public abstract double calculatePressureDragForce(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings);
}

2
core/src/net/sf/openrocket/aerodynamics/barrowman/SymmetricComponentCalc.java
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@ -179,7 +179,7 @@ public class SymmetricComponentCalc extends RocketComponentCalc {
private LinearInterpolator interpolator = null;
@Override
public double calculatePressureCD(FlightConditions conditions,
public double calculatePressureDragForce(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings) {
// Check for simple cases first

22
core/src/net/sf/openrocket/aerodynamics/barrowman/TubeFinSetCalc.java
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@ -622,11 +622,11 @@ public class TubeFinSetCalc extends RocketComponentCalc {
// }
@Override
public double calculatePressureCD(FlightConditions conditions,
public double calculatePressureDragForce(FlightConditions conditions,
double stagnationCD, double baseCD, WarningSet warnings) {
double mach = conditions.getMach();
double cd = 0;
double drag = 0;
// Pressure fore-drag
if (crossSection == FinSet.CrossSection.AIRFOIL ||
@ -634,34 +634,34 @@ public class TubeFinSetCalc extends RocketComponentCalc {
// Round leading edge
if (mach < 0.9) {
cd = Math.pow(1 - pow2(mach), -0.417) - 1;
drag = Math.pow(1 - pow2(mach), -0.417) - 1;
} else if (mach < 1) {
cd = 1 - 1.785 * (mach - 0.9);
drag = 1 - 1.785 * (mach - 0.9);
} else {
cd = 1.214 - 0.502 / pow2(mach) + 0.1095 / pow2(pow2(mach));
drag = 1.214 - 0.502 / pow2(mach) + 0.1095 / pow2(pow2(mach));
}
} else if (crossSection == FinSet.CrossSection.SQUARE) {
cd = stagnationCD;
drag = stagnationCD;
} else {
throw new UnsupportedOperationException("Unsupported fin profile: " + crossSection);
}
// Slanted leading edge
cd *= pow2(cosGammaLead);
drag *= pow2(cosGammaLead);
// Trailing edge drag
if (crossSection == FinSet.CrossSection.SQUARE) {
cd += baseCD;
drag += baseCD;
} else if (crossSection == FinSet.CrossSection.ROUNDED) {
cd += baseCD / 2;
drag += baseCD / 2;
}
// Airfoil assumed to have zero base drag
// Scale to correct reference area
cd *= finCount * span * thickness / conditions.getRefArea();
drag *= finCount * span * thickness / conditions.getRefArea();
return cd;
return drag;
}
private static int calculateInterferenceFinCount(TubeFinSet component) {

4
core/src/net/sf/openrocket/simulation/RK4SimulationStepper.java
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@ -341,7 +341,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
// Linear forces in rocket coordinates
store.dragForce = store.forces.getCDaxial() * dynP * refArea;
store.dragForce = store.forces.getCaxial() * dynP * refArea;
double fN = store.forces.getCN() * dynP * refArea;
double fSide = store.forces.getCside() * dynP * refArea;
@ -646,7 +646,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
if (store.forces != null) {
data.setValue(FlightDataType.TYPE_DRAG_COEFF, store.forces.getCD());
data.setValue(FlightDataType.TYPE_AXIAL_DRAG_COEFF, store.forces.getCDaxial());
data.setValue(FlightDataType.TYPE_AXIAL_DRAG_COEFF, store.forces.getCaxial());
data.setValue(FlightDataType.TYPE_FRICTION_DRAG_COEFF, store.forces.getFrictionCD());
data.setValue(FlightDataType.TYPE_PRESSURE_DRAG_COEFF, store.forces.getPressureCD());
data.setValue(FlightDataType.TYPE_BASE_DRAG_COEFF, store.forces.getBaseCD());

2
core/test/net/sf/openrocket/aerodynamics/SymmetricComponentCalcTest.java
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@ -136,7 +136,7 @@ public class SymmetricComponentCalcTest {
double m = i/20.0;
String buf = "SymmetricComponentCalc produces bad Cd at index " + i + "(m=" + m +")";
conditions.setMach(m);
double testcd = calcObj.calculatePressureCD(conditions, 0.0, 0.0, warnings) *
double testcd = calcObj.calculatePressureDragForce(conditions, 0.0, 0.0, warnings) *
conditions.getRefArea() / frontalArea;
assertEquals(buf, cd[(int) Math.round(m*20)], testcd, EPSILON);
}