public void SimulateAeroProperties(out Vector3 aeroForce, out Vector3 aeroTorque, Vector3 velocityWorldVector, double altitude)
{
// Rodhern: It seems that this method, 'SimulateAeroProperties', is only used in FARAPI, which in turn can be used by say KSPTrajectories.
// The parameter 'FARCenterQuery dummy' is from a code fix by Benjamin Chung (commit 18fbb9d29431679a4de9dfc22a443f400d2d4f8b).
FARCenterQuery center = new FARCenterQuery();
FARCenterQuery dummy = new FARCenterQuery();
float pressure;
float density;
float temperature;
float speedOfSound;
CelestialBody body = vessel.mainBody; //Calculate main gas properties
pressure = (float)body.GetPressure(altitude);
temperature = (float)body.GetTemperature(altitude);
density = (float)body.GetDensity(pressure, temperature);
speedOfSound = (float)body.GetSpeedOfSound(pressure, density);
if (pressure <= 0 || temperature <= 0 || density <= 0 || speedOfSound <= 0)
{
aeroForce = Vector3.zero;
aeroTorque = Vector3.zero;
return;
}
float velocityMag = velocityWorldVector.magnitude;
float machNumber = velocityMag / speedOfSound;
float reynoldsNumber = (float)FARAeroUtil.CalculateReynoldsNumber(density, Length, velocityMag, machNumber, temperature, body.atmosphereAdiabaticIndex);
float reynoldsPerLength = reynoldsNumber / (float)Length;
float pseudoKnudsenNumber = machNumber / (reynoldsNumber + machNumber);
float skinFriction = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
FlightEnv fenv = FlightEnv.NewPredicted(vessel.mainBody, altitude, machNumber);
if (_currentAeroSections != null)
{
for (int i = 0; i < _currentAeroSections.Count; i++)
{
FARAeroSection curSection = _currentAeroSections[i];
if (curSection != null)
{
curSection.PredictionCalculateAeroForces(density, machNumber, reynoldsPerLength, pseudoKnudsenNumber, skinFriction, velocityWorldVector, center);
}
}
for (int i = 0; i < _legacyWingModels.Count; i++)
{
FARWingAerodynamicModel curWing = _legacyWingModels[i];
if ((object)curWing != null)
{
Vector3d force = curWing.PrecomputeCenterOfLift(velocityWorldVector, fenv, dummy);
center.AddForce(curWing.transform.position, force);
}
}
}
aeroForce = center.force;
aeroTorque = center.TorqueAt(vessel.CoM);
}
public void SimulateAeroProperties(out Vector3 aeroForce, out Vector3 aeroTorque, Vector3 velocityWorldVector, double altitude)
{
FARCenterQuery center = new FARCenterQuery();
float pressure;
float density;
float temperature;
float speedOfSound;
CelestialBody body = vessel.mainBody; //Calculate main gas properties
pressure = (float)body.GetPressure(altitude);
temperature = (float)body.GetTemperature(altitude);
density = (float)body.GetDensity(pressure, temperature);
speedOfSound = (float)body.GetSpeedOfSound(pressure, density);
if (pressure <= 0 || temperature <= 0 || density <= 0 || speedOfSound <= 0)
{
aeroForce = Vector3.zero;
aeroTorque = Vector3.zero;
return;
}
float velocityMag = velocityWorldVector.magnitude;
float machNumber = velocityMag / speedOfSound;
float reynoldsNumber = (float)FARAeroUtil.CalculateReynoldsNumber(density, Length, velocityMag, machNumber, temperature, body.atmosphereAdiabaticIndex);
float reynoldsPerLength = reynoldsNumber / (float)Length;
float skinFriction = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
float pseudoKnudsenNumber = machNumber / (reynoldsNumber + machNumber);
if (_currentAeroSections != null)
{
for (int i = 0; i < _currentAeroSections.Count; i++)
{
FARAeroSection curSection = _currentAeroSections[i];
if (curSection != null)
{
curSection.PredictionCalculateAeroForces(density, machNumber, reynoldsPerLength, pseudoKnudsenNumber, skinFriction, velocityWorldVector, center);
}
}
for (int i = 0; i < _legacyWingModels.Count; i++)
{
FARWingAerodynamicModel curWing = _legacyWingModels[i];
if ((object)curWing != null)
{
curWing.PrecomputeCenterOfLift(velocityWorldVector, machNumber, density, center);
}
}
}
aeroForce = center.force;
aeroTorque = center.TorqueAt(vessel.CoM);
}
private void CalculateAndApplyVesselAeroProperties()
{
float atmDensity = (float)vessel.atmDensity;
if (atmDensity <= 0)
{
MachNumber = 0;
ReynoldsNumber = 0;
return;
}
MachNumber = vessel.mach;
ReynoldsNumber = FARAeroUtil.CalculateReynoldsNumber(vessel.atmDensity,
Length,
vessel.srfSpeed,
MachNumber,
FlightGlobals.getExternalTemperature((float)vessel
.altitude,
vessel.mainBody),
vessel.mainBody.atmosphereAdiabaticIndex);
float skinFrictionDragCoefficient = (float)FARAeroUtil.SkinFrictionDrag(ReynoldsNumber, MachNumber);
float pseudoKnudsenNumber = (float)(MachNumber / (ReynoldsNumber + MachNumber));
Vector3 frameVel = Krakensbane.GetFrameVelocityV3f();
//start from the top and come down to improve performance if it needs to remove anything
for (int i = _currentAeroModules.Count - 1; i >= 0; i--)
{
FARAeroPartModule m = _currentAeroModules[i];
if (m != null && m.part != null && m.part.partTransform != null)
{
m.UpdateVelocityAndAngVelocity(frameVel);
}
else
{
_currentAeroModules.RemoveAt(i);
}
}
foreach (FARAeroSection aeroSection in _currentAeroSections)
{
aeroSection.FlightCalculateAeroForces((float)MachNumber,
(float)(ReynoldsNumber / Length),
pseudoKnudsenNumber,
skinFrictionDragCoefficient);
}
_vesselIntakeRamDrag.ApplyIntakeRamDrag((float)MachNumber, vessel.srf_velocity.normalized);
foreach (FARAeroPartModule m in _currentAeroModules)
{
m.ApplyForces();
}
}
private void CalculateAndApplyVesselAeroProperties()
{
float atmDensity = (float)_vessel.atmDensity;
if (atmDensity <= 0)
{
machNumber = 0;
reynoldsNumber = 0;
return;
}
machNumber = _vessel.mach;
reynoldsNumber = FARAeroUtil.CalculateReynoldsNumber(_vessel.atmDensity, Length, _vessel.srfSpeed, machNumber, FlightGlobals.getExternalTemperature((float)_vessel.altitude, _vessel.mainBody), _vessel.mainBody.atmosphereAdiabaticIndex);
float skinFrictionDragCoefficient = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
Vector3 frameVel = Krakensbane.GetFrameVelocityV3f();
if (_updateQueued) //only happens if we have an voxelization scheduled, then we need to check for null
{
for (int i = _currentAeroModules.Count - 1; i >= 0; i--) //start from the top and come down to improve performance if it needs to remove anything
{
FARAeroPartModule m = _currentAeroModules[i];
if (m != null)
{
m.UpdateVelocityAndAngVelocity(frameVel);
}
else
{
_currentAeroModules.RemoveAt(i);
i++;
}
}
}
else //otherwise, we don't need to do Unity's expensive "is this part dead" null-check
{
for (int i = _currentAeroModules.Count - 1; i >= 0; i--) //start from the top and come down to improve performance if it needs to remove anything
{
FARAeroPartModule m = _currentAeroModules[i];
m.UpdateVelocityAndAngVelocity(frameVel);
}
}
for (int i = 0; i < _currentAeroSections.Count; i++)
{
_currentAeroSections[i].FlightCalculateAeroForces(atmDensity, (float)machNumber, (float)(reynoldsNumber / Length), skinFrictionDragCoefficient);
}
_vesselIntakeRamDrag.ApplyIntakeRamDrag((float)machNumber, _vessel.srf_velocity.normalized, (float)_vessel.dynamicPressurekPa);
for (int i = 0; i < _currentAeroModules.Count; i++)
{
FARAeroPartModule m = _currentAeroModules[i];
m.ApplyForces();
}
}
private void CalculateAndApplyVesselAeroProperties()
{
float atmDensity = (float)_vessel.atmDensity;
if (atmDensity <= 0)
{
machNumber = 0;
reynoldsNumber = 0;
return;
}
machNumber = _vessel.mach;
reynoldsNumber = FARAeroUtil.CalculateReynoldsNumber(_vessel.atmDensity, Length, _vessel.srfSpeed, machNumber, FlightGlobals.getExternalTemperature((float)_vessel.altitude, _vessel.mainBody), _vessel.mainBody.atmosphereAdiabaticIndex);
float skinFrictionDragCoefficient = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
Vector3 frameVel = Krakensbane.GetFrameVelocityV3f();
for (int i = 0; i < _currentAeroModules.Count; i++)
{
FARAeroPartModule m = _currentAeroModules[i];
if (m != null)
{
m.UpdateVelocityAndAngVelocity(frameVel);
}
else
{
_currentAeroModules.RemoveAt(i);
i--;
}
}
for (int i = 0; i < _currentAeroSections.Count; i++)
{
_currentAeroSections[i].FlightCalculateAeroForces(atmDensity, (float)machNumber, (float)(reynoldsNumber / Length), skinFrictionDragCoefficient);
}
_vesselIntakeRamDrag.ApplyIntakeRamDrag((float)machNumber, _vessel.srf_velocity.normalized, (float)_vessel.dynamicPressurekPa);
for (int i = 0; i < _currentAeroModules.Count; i++)
{
FARAeroPartModule m = _currentAeroModules[i];
if ((object)m != null)
{
m.ApplyForces();
}
}
}
public void SimulateAeroProperties(out Vector3 aeroForce, out Vector3 aeroTorque, Vector3 velocityWorldVector, double altitude)
{
FARCenterQuery center = new FARCenterQuery();
float pressure;
float density;
float temperature;
float speedOfSound;
CelestialBody body = _vessel.mainBody; //Calculate main gas properties
pressure = (float)body.GetPressure(altitude);
temperature = (float)body.GetTemperature(altitude);
density = (float)body.GetDensity(pressure, temperature);
speedOfSound = (float)body.GetSpeedOfSound(pressure, density);
float velocityMag = velocityWorldVector.magnitude;
float machNumber = velocityMag / speedOfSound;
float reynoldsNumber = (float)FARAeroUtil.CalculateReynoldsNumber(density, Length, velocityMag, machNumber, temperature, body.atmosphereAdiabaticIndex);
float reynoldsPerLength = reynoldsNumber / (float)Length;
float skinFriction = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
float pseudoLanchesterNumber = machNumber / (reynoldsNumber + machNumber);
for (int i = 0; i < _currentAeroSections.Count; i++)
{
_currentAeroSections[i].PredictionCalculateAeroForces(density, machNumber, reynoldsPerLength, pseudoLanchesterNumber, skinFriction, velocityWorldVector, center);
}
for (int i = 0; i < _legacyWingModels.Count; i++)
{
_legacyWingModels[i].PrecomputeCenterOfLift(velocityWorldVector, machNumber, density, center);
}
aeroForce = center.force;
aeroTorque = center.TorqueAt(_vessel.CoM);
}
/// <summary>
/// These are just a few different attempts to figure drag for various blunt bodies
/// </summary>
private void DragModel(Vector3d local_velocity, double M, double rho)
{
// Has the same x/y/z as the vertices in PartMaxBoundaries etc
Vector3d model_velocity = to_model_rotation * local_velocity;
double viscousLift, potentialLift, newtonianLift;
viscousLift = potentialLift = newtonianLift = 0;
double CdAdd = 0;
//float AxialProportion = Vector3.Dot(localUpVector, local_velocity);
double AxialProportion = model_velocity.y;
float AxialProportion_flt = (float)model_velocity.y;
double AxialProportion_2 = AxialProportion * AxialProportion;
double OneMinusAxial_2 = Math.Abs(1 - AxialProportion_2);
double M_2 = M * M;
double M_2_recip = 1 / M_2;
double maxPressureCoeff;
if (FARDebugValues.useSplinesForSupersonicMath)
{
maxPressureCoeff = FARAeroUtil.MaxPressureCoefficient.Evaluate((float)M);
}
else
{
maxPressureCoeff = FARAeroUtil.MaxPressureCoefficientCalc(M);
}
double sepFlowCd = SeparatedFlowDrag(M, M_2, M_2_recip);
//This handles elliptical and other non-circular cross sections
//float crossflowParameter = Vector3.Dot(localForwardVector, Vector3.Exclude(localUpVector, local_velocity).normalized);
//crossflowParameter *= crossflowParameter;
double crossflowParameter = model_velocity.z * model_velocity.z;
double crossflow = model_velocity.x * model_velocity.x + crossflowParameter;
if (crossflow != 0)
{
crossflowParameter /= crossflow;
}
crossflowParameter = crossflowParameter * majorMinorAxisRatio + (1 - crossflowParameter) / majorMinorAxisRatio;
if (AxialProportion_2 > 0.98)
{
crossflowParameter *= 50 * OneMinusAxial_2;
}
Cd += CdCurve.Evaluate(AxialProportion_flt);
viscousLift = ClViscousCurve.Evaluate(AxialProportion_flt);
double axialDirectionFactor = cosAngleCutoff * AxialProportion;
if (axialDirectionFactor > 0)
{
Cd = Math.Min(Cd, sepFlowCd * taperCrossSectionAreaRatio) * AxialProportion_2 + Cd * OneMinusAxial_2;
}
else
{
Cd = Math.Min(Cd, maxPressureCoeff * taperCrossSectionAreaRatio) * AxialProportion_2 + Cd * OneMinusAxial_2;
}
if (M_2 > 1)
{
potentialLift = ClPotentialCurve.Evaluate(AxialProportion_flt) * M_2_recip;
}
else
{
potentialLift = ClPotentialCurve.Evaluate(AxialProportion_flt);
}
Cm = CmCurve.Evaluate(AxialProportion_flt) * 0.1;
CoDshift = CenterOfDrag;
double MachMultiplier = MachDragEffect(M);
Cd *= MachMultiplier;
if (HighLogic.LoadedSceneIsFlight)
{
Cd += FARAeroUtil.SkinFrictionDrag(rho, lengthScale, local_velocity.magnitude, M, FlightGlobals.getExternalTemperature(part.transform.position) + FARAeroUtil.currentBodyTemp); //Skin friction drag
}
else
{
Cd += 0.005;
}
for (int i = 0; i < attachNodeDragList.Count; i++)
{
attachNodeData node = attachNodeDragList[i];
double dotProd = Vector3d.Dot(node.location.normalized, local_velocity);
double tmp = 0;
double Cltmp = 0;
if (dotProd < 0)
{
dotProd *= dotProd;
tmp = sepFlowCd;
// Cltmp = tmp * (dotProd - 1);
// Cltmp *= pair.Value;
tmp *= node.areaValue * dotProd;
// Vector3 CoDshiftOffset = -Vector3.Exclude(pair.Key, part.transform.worldToLocalMatrix.MultiplyVector(velocity.normalized)).normalized;
// CoDshiftOffset *= Mathf.Sqrt(Mathf.Clamp01(1 - dotProd));
// CoDshiftOffset *= Mathf.Sqrt(1.5f * pair.Value);
CoDshift += node.location * (tmp / (tmp + Cd));
}
else
{
Vector3d worldPairVec = part_transform.TransformDirection(node.location.normalized);
double dotProd_2 = dotProd * dotProd;
double liftProd_2 = 1 - dotProd_2;
double liftProd = Vector3d.Dot(worldPairVec, liftDir);
double forceCoefficient = dotProd_2 * bluntBodyCosForceParameter;
forceCoefficient += liftProd_2 * bluntBodySinForceParameter;
forceCoefficient *= maxPressureCoeff * node.areaValue; //force applied perependicular to the flat end of the node
tmp = forceCoefficient * dotProd;
Cltmp = -forceCoefficient * liftProd; //negative because lift is in opposite direction of projection of velocity vector onto node direction
double Cmtmp = dotProd * liftProd * bluntBodyMomentParameter;
Cmtmp *= node.areaValue * node.recipDiameter;
if (!node.pitchesAwayFromUpVec)
{
Cmtmp *= -1;
}
Cm += Cmtmp;
double tmpCdCl = Math.Sqrt(tmp * tmp + Cltmp * Cltmp);
CoDshift += node.location * (tmpCdCl / (tmpCdCl + Math.Sqrt(Cd * Cd + Cl * Cl)));
/*double liftProd = Vector3d.Dot(worldPairVec, liftDir);
*
* tmp = maxPressureCoeff * dotProd_2 * dotProd;
* tmp *= node.areaValue;
*
* Cltmp = maxPressureCoeff * dotProd_2 * liftProd;
* Cltmp *= -node.areaValue;
*
* double radius = Math.Sqrt(node.areaValue / Math.PI);
* Vector3 CoDshiftOffset = Vector3.Exclude(node.location, local_velocity).normalized;
* CoDshiftOffset *= (float)(Math.Abs(liftProd) * radius * 0.4);
*
* double Cmtmp;
* if (node.pitchesAwayFromUpVec)
* Cmtmp = -0.325 * radius * node.areaValue / S * Math.Abs(liftProd);
* else
* Cmtmp = 0.325 * radius * node.areaValue / S * Math.Abs(liftProd);
*
* double tmpCdCl = Math.Sqrt(tmp * tmp + Cltmp * Cltmp);
*
* CoDshift += node.location * (tmpCdCl / (tmpCdCl + Math.Sqrt(Cd * Cd + Cl * Cl))) + CoDshiftOffset;
*
* Cm += Cmtmp;*/
}
CdAdd += tmp;
newtonianLift += Cltmp;
}
viscousLift *= MachMultiplier;
Cd += CdAdd;
Cl = viscousLift + potentialLift;
Cl *= crossflowParameter;
Cm *= crossflowParameter;
Cl += newtonianLift;
// Debug.Log("Cd = " + Cd + " Cl = " + Cl + " Cm = " + Cm + "\nPot Lift = " + potentialLift + " Visc Lift = " + viscousLift + " Newt Lift = " + newtonianLift + "\nCdAdd = " + CdAdd + " sepFlowCd = " + sepFlowCd + " maxPressureCoeff = " + maxPressureCoeff + "\ntaperCrossSectionAreaRatio = " + taperCrossSectionAreaRatio + " crossflowParameter = " + crossflowParameter);
}
public void SimulateAeroProperties(
out Vector3 aeroForce,
out Vector3 aeroTorque,
Vector3 velocityWorldVector,
double altitude
)
{
Vector3d position = vessel.CurrentPosition(altitude);
if (velocityWorldVector.NearlyEqual(lastSimResults.VelocityVector) &&
(FARAtmosphere.IsCustom
// Custom atmospheres are not guaranteed to be independent of latitude and longitude
? position.NearlyEqual(lastSimResults.Position)
: altitude.NearlyEqual(lastSimResults.Position.z)))
{
aeroForce = lastSimResults.Force;
aeroTorque = lastSimResults.Torque;
return;
}
var center = new FARCenterQuery();
var dummy = new FARCenterQuery();
//Calculate main gas properties
GasProperties properties = FARAtmosphere.GetGasProperties(vessel.mainBody, position, Planetarium.GetUniversalTime());
if (properties.Pressure <= 0 || properties.Temperature <= 0)
{
aeroForce = Vector3.zero;
aeroTorque = Vector3.zero;
return;
}
float velocityMag = velocityWorldVector.magnitude;
float machNumber = (float)(velocityMag / properties.SpeedOfSound);
float reynoldsNumber = (float)FARAeroUtil.CalculateReynoldsNumber(properties.Density,
Length,
velocityMag,
machNumber,
properties.Temperature,
properties.AdiabaticIndex);
float reynoldsPerLength = reynoldsNumber / (float)Length;
float skinFriction = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
float pseudoKnudsenNumber = machNumber / (reynoldsNumber + machNumber);
if (_currentAeroSections != null)
{
foreach (FARAeroSection curSection in _currentAeroSections)
{
curSection?.PredictionCalculateAeroForces((float)properties.Density,
machNumber,
reynoldsPerLength,
pseudoKnudsenNumber,
skinFriction,
velocityWorldVector,
center);
}
foreach (FARWingAerodynamicModel curWing in _legacyWingModels)
{
if (curWing != null)
{
center.AddForce(curWing.transform.position,
curWing.PrecomputeCenterOfLift(velocityWorldVector,
machNumber,
properties.Density,
dummy));
}
}
}
aeroForce = center.force;
aeroTorque = center.TorqueAt(vessel.CoM);
lastSimResults = new CachedSimResults(velocityWorldVector, position, aeroForce, aeroTorque);
}
public void SimulateAeroProperties(
out Vector3 aeroForce,
out Vector3 aeroTorque,
Vector3 velocityWorldVector,
double altitude
)
{
var center = new FARCenterQuery();
var dummy = new FARCenterQuery();
//Calculate main gas properties
GasProperties properties = FARAtmosphere.GetGasProperties(vessel, altitude, Planetarium.GetUniversalTime());
if (properties.Pressure <= 0 || properties.Temperature <= 0)
{
aeroForce = Vector3.zero;
aeroTorque = Vector3.zero;
return;
}
float velocityMag = velocityWorldVector.magnitude;
float machNumber = (float)(velocityMag / properties.SpeedOfSound);
float reynoldsNumber = (float)FARAeroUtil.CalculateReynoldsNumber(properties.Density,
Length,
velocityMag,
machNumber,
properties.Temperature,
properties.AdiabaticIndex);
float reynoldsPerLength = reynoldsNumber / (float)Length;
float skinFriction = (float)FARAeroUtil.SkinFrictionDrag(reynoldsNumber, machNumber);
float pseudoKnudsenNumber = machNumber / (reynoldsNumber + machNumber);
if (_currentAeroSections != null)
{
foreach (FARAeroSection curSection in _currentAeroSections)
{
curSection?.PredictionCalculateAeroForces((float)properties.Density,
machNumber,
reynoldsPerLength,
pseudoKnudsenNumber,
skinFriction,
velocityWorldVector,
center);
}
foreach (FARWingAerodynamicModel curWing in _legacyWingModels)
{
if (curWing != null)
{
center.AddForce(curWing.transform.position,
curWing.PrecomputeCenterOfLift(velocityWorldVector,
machNumber,
properties.Density,
dummy));
}
}
}
aeroForce = center.force;
aeroTorque = center.TorqueAt(vessel.CoM);
}
