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Correct calculateFrictionDrag() to iterate through all instances of components

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This commit is contained in:
JoePfeiffer 2020-03-19 11:01:14 -06:00
parent af3d226b2b
commit 5483c3e659
1 changed files with 76 additions and 72 deletions
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148
core/src/net/sf/openrocket/aerodynamics/BarrowmanCalculator.java
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@ -392,84 +392,90 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
double[] roughnessLimited = new double[Finish.values().length];
Arrays.fill(roughnessLimited, Double.NaN);
for (RocketComponent c : configuration.getActiveComponents()) {
final InstanceMap imap = configuration.getActiveInstances();
for(Map.Entry<RocketComponent, ArrayList<InstanceContext>> entry: imap.entrySet() ) {
final RocketComponent c = entry.getKey();
// Consider only SymmetricComponents and FinSets:
if (!(c instanceof SymmetricComponent) &&
!(c instanceof FinSet))
continue;
// Calculate the roughness-limited friction coefficient
Finish finish = ((ExternalComponent) c).getFinish();
if (Double.isNaN(roughnessLimited[finish.ordinal()])) {
roughnessLimited[finish.ordinal()] =
0.032 * Math.pow(finish.getRoughnessSize() / configuration.getLength(), 0.2) *
roughnessCorrection;
}
/*
* Actual Cf is maximum of Cf and the roughness-limited value.
* For perfect finish require additionally that Re > 1e6
*/
double componentCf;
if (configuration.getRocket().isPerfectFinish()) {
// For perfect finish require Re > 1e6
if ((Re > 1.0e6) && (roughnessLimited[finish.ordinal()] > Cf)) {
componentCf = roughnessLimited[finish.ordinal()];
} else {
componentCf = Cf;
}
} else {
// For fully turbulent use simple max
componentCf = Math.max(Cf, roughnessLimited[finish.ordinal()]);
}
//Handle Overriden CD for Whole Rocket
if(c.isCDOverridden()) {
continue;
}
// Calculate the friction drag:
if (c instanceof SymmetricComponent) {
SymmetricComponent s = (SymmetricComponent) c;
bodyFriction += componentCf * s.getComponentWetArea();
if (map != null) {
// Corrected later
map.get(c).setFrictionCD(componentCf * s.getComponentWetArea()
/ conditions.getRefArea());
}
double r = Math.max(s.getForeRadius(), s.getAftRadius());
if (r > maxR)
maxR = r;
len += c.getLength();
} else if (c instanceof FinSet) {
FinSet f = (FinSet) c;
double mac = ((FinSetCalc) calcMap.get(c)).getMACLength();
double cd = componentCf * (1 + 2 * f.getThickness() / mac) *
2 * f.getFinCount() * f.getPlanformArea();
finFriction += cd;
if (map != null) {
map.get(c).setFrictionCD(cd / conditions.getRefArea());
}
}
// iterate across component instances
final ArrayList<InstanceContext> contextList = entry.getValue();
for(InstanceContext context: contextList ) {
// Calculate the roughness-limited friction coefficient
Finish finish = ((ExternalComponent) c).getFinish();
if (Double.isNaN(roughnessLimited[finish.ordinal()])) {
roughnessLimited[finish.ordinal()] =
0.032 * Math.pow(finish.getRoughnessSize() / configuration.getLength(), 0.2) *
roughnessCorrection;
}
/*
* Actual Cf is maximum of Cf and the roughness-limited value.
* For perfect finish require additionally that Re > 1e6
*/
double componentCf;
if (configuration.getRocket().isPerfectFinish()) {
// For perfect finish require Re > 1e6
if ((Re > 1.0e6) && (roughnessLimited[finish.ordinal()] > Cf)) {
componentCf = roughnessLimited[finish.ordinal()];
} else {
componentCf = Cf;
}
} else {
// For fully turbulent use simple max
componentCf = Math.max(Cf, roughnessLimited[finish.ordinal()]);
}
//Handle Overriden CD for Whole Rocket
if(c.isCDOverridden()) {
continue;
}
// Calculate the friction drag:
if (c instanceof SymmetricComponent) {
SymmetricComponent s = (SymmetricComponent) c;
bodyFriction += componentCf * s.getComponentWetArea();
if (map != null) {
// Corrected later
map.get(c).setFrictionCD(componentCf * s.getComponentWetArea()
/ conditions.getRefArea());
}
double r = Math.max(s.getForeRadius(), s.getAftRadius());
if (r > maxR)
maxR = r;
len += c.getLength();
} else if (c instanceof FinSet) {
FinSet f = (FinSet) c;
double mac = ((FinSetCalc) calcMap.get(c)).getMACLength();
double cd = componentCf * (1 + 2 * f.getThickness() / mac) *
2 * f.getPlanformArea();
finFriction += cd;
if (map != null) {
map.get(c).setFrictionCD(cd / conditions.getRefArea());
}
}
}
}
// fB may be POSITIVE_INFINITY, but that's ok for us
double fB = (len + 0.0001) / maxR;
double correction = (1 + 1.0 / (2 * fB));
@ -482,8 +488,6 @@ public class BarrowmanCalculator extends AbstractAerodynamicCalculator {
}
}
}
return (finFriction + correction * bodyFriction) / conditions.getRefArea();
}