/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Module: FGAtmosphere.cpp
- Author: Jon Berndt
- Implementation of 1959 Standard Atmosphere added by Tony Peden
- Date started: 11/24/98
- Purpose: Models the atmosphere
- Called by: FGSimExec
+ Author: Jon Berndt, Tony Peden
+ Date started: 6/2011
+ Purpose: Models an atmosphere interface class
+ Called by: FGFDMExec
- ------------- Copyright (C) 1999 Jon S. Berndt (jon@jsbsim.org) -------------
+ ------------- Copyright (C) 2011 Jon S. Berndt (jon@jsbsim.org) -------------
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
FUNCTIONAL DESCRIPTION
--------------------------------------------------------------------------------
-Models the atmosphere. The equation used below was determined by a third order
-curve fit using Excel. The data is from the ICAO atmosphere model.
+This models a base atmosphere class to serve as a common interface to any derived
+atmosphere models.
HISTORY
--------------------------------------------------------------------------------
-11/24/98 JSB Created
-07/23/99 TP Added implementation of 1959 Standard Atmosphere
- Moved calculation of Mach number to FGPropagate
- Later updated to '76 model
+6/18/2011 Started Jon S. Berndt
+
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
COMMENTS, REFERENCES, and NOTES
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-[1] Anderson, John D. "Introduction to Flight, Third Edition", McGraw-Hill,
- 1989, ISBN 0-07-001641-0
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
INCLUDES
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
-#include "FGAtmosphere.h"
-#include "FGAircraft.h"
-#include "FGPropagate.h"
-#include "FGInertial.h"
-#include "FGAuxiliary.h"
-#include "FGFDMExec.h"
-#include "input_output/FGPropertyManager.h"
#include <iostream>
+#include <iomanip>
#include <cstdlib>
-
-using namespace std;
+#include "FGFDMExec.h"
+#include "FGAtmosphere.h"
namespace JSBSim {
-static const char *IdSrc = "$Id: FGAtmosphere.cpp,v 1.38 2010/09/16 11:01:24 jberndt Exp $";
+static const char *IdSrc = "$Id: FGAtmosphere.cpp,v 1.51 2012/04/13 13:18:28 jberndt Exp $";
static const char *IdHdr = ID_ATMOSPHERE;
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
CLASS IMPLEMENTATION
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
-FGAtmosphere::FGAtmosphere(FGFDMExec* fdmex) : FGModel(fdmex)
+FGAtmosphere::FGAtmosphere(FGFDMExec* fdmex) : FGModel(fdmex),
+ PressureAltitude(0.0), // ft
+ DensityAltitude(0.0), // ft
+ SutherlandConstant(198.72), // deg Rankine
+ Beta(2.269690E-08) // slug/(sec ft R^0.5)
{
Name = "FGAtmosphere";
- lastIndex = 0;
- h = 0.0;
- psiw = 0.0;
- htab[0]=0;
- htab[1]= 36089.0;
- htab[2]= 65617.0;
- htab[3]=104987.0;
- htab[4]=154199.0;
- htab[5]=167322.0;
- htab[6]=232940.0;
- htab[7]=278385.0; //ft.
-
- MagnitudedAccelDt = MagnitudeAccel = Magnitude = 0.0;
-// SetTurbType( ttCulp );
- SetTurbType( ttNone );
- TurbGain = 1.0;
- TurbRate = 10.0;
- Rhythmicity = 0.1;
- spike = target_time = strength = 0.0;
- wind_from_clockwise = 0.0;
- SutherlandConstant = 198.72; // deg Rankine
- Beta = 2.269690E-08; // slug/(sec ft R^0.5)
-
- T_dev_sl = T_dev = delta_T = 0.0;
- StandardTempOnly = false;
- first_pass = true;
- vGustNED.InitMatrix();
- vTurbulenceNED.InitMatrix();
-
- // Milspec turbulence model
- windspeed_at_20ft = 0.;
- probability_of_exceedence_index = 0;
- POE_Table = new FGTable(7,12);
- // this is Figure 7 from p. 49 of MIL-F-8785C
- // rows: probability of exceedance curve index, cols: altitude in ft
- *POE_Table
- << 500.0 << 1750.0 << 3750.0 << 7500.0 << 15000.0 << 25000.0 << 35000.0 << 45000.0 << 55000.0 << 65000.0 << 75000.0 << 80000.0
- << 1 << 3.2 << 2.2 << 1.5 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0
- << 2 << 4.2 << 3.6 << 3.3 << 1.6 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0
- << 3 << 6.6 << 6.9 << 7.4 << 6.7 << 4.6 << 2.7 << 0.4 << 0.0 << 0.0 << 0.0 << 0.0 << 0.0
- << 4 << 8.6 << 9.6 << 10.6 << 10.1 << 8.0 << 6.6 << 5.0 << 4.2 << 2.7 << 0.0 << 0.0 << 0.0
- << 5 << 11.8 << 13.0 << 16.0 << 15.1 << 11.6 << 9.7 << 8.1 << 8.2 << 7.9 << 4.9 << 3.2 << 2.1
- << 6 << 15.6 << 17.6 << 23.0 << 23.6 << 22.1 << 20.0 << 16.0 << 15.1 << 12.1 << 7.9 << 6.2 << 5.1
- << 7 << 18.7 << 21.5 << 28.4 << 30.2 << 30.7 << 31.0 << 25.2 << 23.1 << 17.5 << 10.7 << 8.4 << 7.2;
bind();
Debug(0);
bool FGAtmosphere::InitModel(void)
{
- if (!FGModel::InitModel()) return false;
+ Calculate(0.0);
+ SLtemperature = Temperature = 518.67;
+ SLpressure = Pressure = 2116.22;
+ SLdensity = Density = Pressure/(Reng*Temperature);
+ SLsoundspeed = Soundspeed = sqrt(SHRatio*Reng*(Temperature));
- UseInternal(); // this is the default
-
- Calculate(h);
- StdSLtemperature = SLtemperature = 518.67;
- StdSLpressure = SLpressure = 2116.22;
- StdSLdensity = SLdensity = 0.00237767;
- StdSLsoundspeed = SLsoundspeed = sqrt(SHRatio*Reng*StdSLtemperature);
- rSLtemperature = 1.0/StdSLtemperature;
- rSLpressure = 1.0/StdSLpressure;
- rSLdensity = 1.0/StdSLdensity;
- rSLsoundspeed = 1.0/StdSLsoundspeed;
+ rSLtemperature = 1/SLtemperature ;
+ rSLpressure = 1/SLpressure ;
+ rSLdensity = 1/SLdensity ;
+ rSLsoundspeed = 1/SLsoundspeed ;
return true;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-bool FGAtmosphere::Run(void)
+bool FGAtmosphere::Run(bool Holding)
{
- if (FGModel::Run()) return true;
- if (FDMExec->Holding()) return false;
-
- RunPreFunctions();
-
- T_dev = 0.0;
- h = Propagate->GetAltitudeASL();
+ if (FGModel::Run(Holding)) return true;
+ if (Holding) return false;
- if (!useExternal) {
- Calculate(h);
- CalculateDerived();
- } else {
- CalculateDerived();
- }
-
- RunPostFunctions();
+ Calculate(in.altitudeASL);
Debug(2);
return false;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-//
-// See reference 1
void FGAtmosphere::Calculate(double altitude)
{
- double slope, reftemp, refpress;
- int i = lastIndex;
-
- if (altitude < htab[lastIndex]) {
- if (altitude <= 0) {
- i = 0;
- altitude=0;
- } else {
- i = lastIndex-1;
- while (htab[i] > altitude) i--;
- }
- } else if (altitude > htab[lastIndex+1]) {
- if (altitude >= htab[7]) {
- i = 7;
- altitude = htab[7];
- } else {
- i = lastIndex+1;
- while (htab[i+1] < altitude) i++;
- }
- }
-
- switch(i) {
- case 0: // Sea level
- slope = -0.00356616; // R/ft.
- reftemp = 518.67; // in degrees Rankine, 288.15 Kelvin
- refpress = 2116.22; // psf
- //refdens = 0.00237767; // slugs/cubic ft.
- break;
- case 1: // 36089 ft. or 11 km
- slope = 0;
- reftemp = 389.97; // in degrees Rankine, 216.65 Kelvin
- refpress = 472.763;
- //refdens = 0.000706032;
- break;
- case 2: // 65616 ft. or 20 km
- slope = 0.00054864;
- reftemp = 389.97; // in degrees Rankine, 216.65 Kelvin
- refpress = 114.636;
- //refdens = 0.000171306;
- break;
- case 3: // 104986 ft. or 32 km
- slope = 0.001536192;
- reftemp = 411.57; // in degrees Rankine, 228.65 Kelvin
- refpress = 18.128;
- //refdens = 1.18422e-05;
- break;
- case 4: // 154199 ft. 47 km
- slope = 0;
- reftemp = 487.17; // in degrees Rankine, 270.65 Kelvin
- refpress = 2.316;
- //refdens = 4.00585e-7;
- break;
- case 5: // 167322 ft. or 51 km
- slope = -0.001536192;
- reftemp = 487.17; // in degrees Rankine, 270.65 Kelvin
- refpress = 1.398;
- //refdens = 8.17102e-7;
- break;
- case 6: // 232940 ft. or 71 km
- slope = -0.00109728;
- reftemp = 386.368; // in degrees Rankine, 214.649 Kelvin
- refpress = 0.0826;
- //refdens = 8.77702e-9;
- break;
- case 7: // 278385 ft. or 84.8520 km
- slope = 0;
- reftemp = 336.5; // in degrees Rankine, 186.94 Kelvin
- refpress = 0.00831;
- //refdens = 2.19541e-10;
- break;
- default: // sea level
- slope = -0.00356616; // R/ft.
- reftemp = 518.67; // in degrees Rankine, 288.15 Kelvin
- refpress = 2116.22; // psf
- //refdens = 0.00237767; // slugs/cubic ft.
- break;
-
- }
-
- // If delta_T is set, then that is our temperature deviation at any altitude.
- // If not, then we'll estimate a deviation based on the sea level deviation (if set).
-
- if(!StandardTempOnly) {
- T_dev = 0.0;
- if (delta_T != 0.0) {
- T_dev = delta_T;
- } else {
- if ((altitude < 36089.239) && (T_dev_sl != 0.0)) {
- T_dev = T_dev_sl * ( 1.0 - (altitude/36089.239));
- }
- }
- reftemp+=T_dev;
- }
-
- if (slope == 0) {
- intTemperature = reftemp;
- intPressure = refpress*exp(-Inertial->SLgravity()/(reftemp*Reng)*(altitude-htab[i]));
- intDensity = intPressure/(Reng*intTemperature);
- } else {
- intTemperature = reftemp+slope*(altitude-htab[i]);
- intPressure = refpress*pow(intTemperature/reftemp,-Inertial->SLgravity()/(slope*Reng));
- intDensity = intPressure/(Reng*intTemperature);
- }
-
- lastIndex=i;
-}
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Calculate parameters derived from T, P and rho
-// Sum gust and turbulence values in NED frame into the wind vector.
-
-void FGAtmosphere::CalculateDerived(void)
-{
- T_dev = (*temperature) - GetTemperature(h);
-
- if (T_dev == 0.0) density_altitude = h;
- else density_altitude = 518.67/0.00356616 * (1.0 - pow(GetDensityRatio(),0.235));
-
- if (turbType != ttNone) Turbulence();
-
- vTotalWindNED = vWindNED + vGustNED + vTurbulenceNED;
-
- // psiw (Wind heading) is the direction the wind is blowing towards
- if (vWindNED(eX) != 0.0) psiw = atan2( vWindNED(eY), vWindNED(eX) );
- if (psiw < 0) psiw += 2*M_PI;
-
- soundspeed = sqrt(SHRatio*Reng*(*temperature));
-
- intViscosity = Beta * pow(intTemperature, 1.5) / (SutherlandConstant + intTemperature);
- intKinematicViscosity = intViscosity / intDensity;
-}
-
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Get the standard atmospheric properties at a specified altitude
-
-void FGAtmosphere::GetStdAtmosphere(double altitude) {
- StandardTempOnly = true;
- Calculate(altitude);
- StandardTempOnly = false;
- atmosphere.Temperature = intTemperature;
- atmosphere.Pressure = intPressure;
- atmosphere.Density = intDensity;
-
- // Reset the internal atmospheric state
- Calculate(h);
-}
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Get the standard pressure at a specified altitude
-
-double FGAtmosphere::GetPressure(double altitude) {
- GetStdAtmosphere(altitude);
- return atmosphere.Pressure;
-}
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Get the standard temperature at a specified altitude
-
-double FGAtmosphere::GetTemperature(double altitude) {
- GetStdAtmosphere(altitude);
- return atmosphere.Temperature;
+ Temperature = GetTemperature(altitude);
+ Pressure = GetPressure(altitude);
+ Density = Pressure/(Reng*Temperature);
+ Soundspeed = sqrt(SHRatio*Reng*(Temperature));
+ PressureAltitude = altitude;
+ DensityAltitude = altitude;
+
+ Viscosity = Beta * pow(Temperature, 1.5) / (SutherlandConstant + Temperature);
+ KinematicViscosity = Viscosity / Density;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// Get the standard density at a specified altitude
-double FGAtmosphere::GetDensity(double altitude) {
- GetStdAtmosphere(altitude);
- return atmosphere.Density;
-}
-
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-// square a value, but preserve the original sign
-
-static inline double square_signed (double value)
+void FGAtmosphere::SetPressureSL(ePressure unit, double pressure)
{
- if (value < 0)
- return value * value * -1;
- else
- return value * value;
-}
+ double press = ConvertToPSF(pressure, unit);
-/// simply square a value
-static inline double sqr(double x) { return x*x; }
-
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-//
-// psi is the angle that the wind is blowing *towards*
-
-void FGAtmosphere::SetWindspeed(double speed)
-{
- if (vWindNED.Magnitude() == 0.0) {
- psiw = 0.0;
- vWindNED(eNorth) = speed;
- } else {
- vWindNED(eNorth) = speed * cos(psiw);
- vWindNED(eEast) = speed * sin(psiw);
- vWindNED(eDown) = 0.0;
- }
+ SLpressure = press;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+// Get the modeled density at a specified altitude
-double FGAtmosphere::GetWindspeed(void) const
+double FGAtmosphere::GetDensity(double altitude) const
{
- return vWindNED.Magnitude();
+ return GetPressure(altitude)/(Reng * GetTemperature(altitude));
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-//
-// psi is the angle that the wind is blowing *towards*
+// This function sets the sea level temperature.
+// Internally, the Rankine scale is used for calculations, so any temperature
+// supplied must be converted to that unit.
-void FGAtmosphere::SetWindPsi(double dir)
+void FGAtmosphere::SetTemperatureSL(double t, eTemperature unit)
{
- double mag = GetWindspeed();
- psiw = dir;
- SetWindspeed(mag);
+ SLtemperature = ConvertToRankine(t, unit);
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-void FGAtmosphere::Turbulence(void)
+double FGAtmosphere::ConvertToRankine(double t, eTemperature unit) const
{
- double DeltaT = rate*FDMExec->GetDeltaT();
-
- switch (turbType) {
- case ttStandard: {
- // TurbGain = TurbGain * TurbGain * 100.0; // what is this!?
-
- vDirectiondAccelDt(eX) = 1 - 2.0*(double(rand())/double(RAND_MAX));
- vDirectiondAccelDt(eY) = 1 - 2.0*(double(rand())/double(RAND_MAX));
- vDirectiondAccelDt(eZ) = 1 - 2.0*(double(rand())/double(RAND_MAX));
-
- MagnitudedAccelDt = 1 - 2.0*(double(rand())/double(RAND_MAX)) - Magnitude;
- // Scale the magnitude so that it moves
- // away from the peaks
- MagnitudedAccelDt = ((MagnitudedAccelDt - Magnitude) /
- (1 + fabs(Magnitude)));
- MagnitudeAccel += MagnitudedAccelDt*TurbRate*DeltaT;
- Magnitude += MagnitudeAccel*DeltaT;
- Magnitude = fabs(Magnitude);
-
- vDirectiondAccelDt.Normalize();
-
- // deemphasise non-vertical forces
- vDirectiondAccelDt(eX) = square_signed(vDirectiondAccelDt(eX));
- vDirectiondAccelDt(eY) = square_signed(vDirectiondAccelDt(eY));
-
- vDirectionAccel += vDirectiondAccelDt*TurbRate*DeltaT;
- vDirectionAccel.Normalize();
- vDirection += vDirectionAccel*DeltaT;
-
- vDirection.Normalize();
-
- // Diminish turbulence within three wingspans
- // of the ground
- vTurbulenceNED = TurbGain * Magnitude * vDirection;
- double HOverBMAC = Auxiliary->GetHOverBMAC();
- if (HOverBMAC < 3.0)
- vTurbulenceNED *= (HOverBMAC / 3.0) * (HOverBMAC / 3.0);
-
- // I don't believe these next two statements calculate the proper gradient over
- // the aircraft body. One reason is because this has no relationship with the
- // orientation or velocity of the aircraft, which it must have. What is vTurbulenceGrad
- // supposed to represent? And the direction and magnitude of the turbulence can change,
- // so both accelerations need to be accounted for, no?
-
- // Need to determine the turbulence change in body axes between two time points.
-
- vTurbulenceGrad = TurbGain*MagnitudeAccel * vDirection;
- vBodyTurbGrad = Propagate->GetTl2b()*vTurbulenceGrad;
-
- if (Aircraft->GetWingSpan() > 0) {
- vTurbPQR(eP) = vBodyTurbGrad(eY)/Aircraft->GetWingSpan();
- } else {
- vTurbPQR(eP) = vBodyTurbGrad(eY)/30.0;
- }
-// if (Aircraft->GetHTailArm() != 0.0)
-// vTurbPQR(eQ) = vBodyTurbGrad(eZ)/Aircraft->GetHTailArm();
-// else
-// vTurbPQR(eQ) = vBodyTurbGrad(eZ)/10.0;
-
- if (Aircraft->GetVTailArm() > 0)
- vTurbPQR(eR) = vBodyTurbGrad(eX)/Aircraft->GetVTailArm();
- else
- vTurbPQR(eR) = vBodyTurbGrad(eX)/10.0;
-
- // Clear the horizontal forces
- // actually felt by the plane, now
- // that we've used them to calculate
- // moments.
- // Why? (JSB)
-// vTurbulenceNED(eX) = 0.0;
-// vTurbulenceNED(eY) = 0.0;
+ double targetTemp=0; // in degrees Rankine
+ switch(unit) {
+ case eFahrenheit:
+ targetTemp = t + 459.67;
break;
- }
- case ttBerndt: { // This is very experimental and incomplete at the moment.
-
- vDirectiondAccelDt(eX) = GaussianRandomNumber();
- vDirectiondAccelDt(eY) = GaussianRandomNumber();
- vDirectiondAccelDt(eZ) = GaussianRandomNumber();
-/*
- MagnitudedAccelDt = GaussianRandomNumber();
- MagnitudeAccel += MagnitudedAccelDt * DeltaT;
- Magnitude += MagnitudeAccel * DeltaT;
-*/
- Magnitude += GaussianRandomNumber() * DeltaT;
-
- vDirectiondAccelDt.Normalize();
- vDirectionAccel += TurbRate * vDirectiondAccelDt * DeltaT;
- vDirectionAccel.Normalize();
- vDirection += vDirectionAccel*DeltaT;
-
- // Diminish z-vector within two wingspans of the ground
- double HOverBMAC = Auxiliary->GetHOverBMAC();
- if (HOverBMAC < 2.0) vDirection(eZ) *= HOverBMAC / 2.0;
-
- vDirection.Normalize();
-
- vTurbulenceNED = TurbGain*Magnitude * vDirection;
- vTurbulenceGrad = TurbGain*MagnitudeAccel * vDirection;
-
- vBodyTurbGrad = Propagate->GetTl2b() * vTurbulenceGrad;
- vTurbPQR(eP) = vBodyTurbGrad(eY) / Aircraft->GetWingSpan();
- if (Aircraft->GetHTailArm() > 0)
- vTurbPQR(eQ) = vBodyTurbGrad(eZ) / Aircraft->GetHTailArm();
- else
- vTurbPQR(eQ) = vBodyTurbGrad(eZ) / 10.0;
-
- if (Aircraft->GetVTailArm() > 0)
- vTurbPQR(eR) = vBodyTurbGrad(eX) / Aircraft->GetVTailArm();
- else
- vTurbPQR(eR) = vBodyTurbGrad(eX)/10.0;
-
+ case eCelsius:
+ targetTemp = t*9.0/5.0 + 32.0 + 459.67;
break;
- }
- case ttCulp: {
-
- vTurbPQR(eP) = wind_from_clockwise;
- if (TurbGain == 0.0) return;
-
- // keep the inputs within allowable limts for this model
- if (TurbGain < 0.0) TurbGain = 0.0;
- if (TurbGain > 1.0) TurbGain = 1.0;
- if (TurbRate < 0.0) TurbRate = 0.0;
- if (TurbRate > 30.0) TurbRate = 30.0;
- if (Rhythmicity < 0.0) Rhythmicity = 0.0;
- if (Rhythmicity > 1.0) Rhythmicity = 1.0;
-
- // generate a sine wave corresponding to turbulence rate in hertz
- double time = FDMExec->GetSimTime();
- double sinewave = sin( time * TurbRate * 6.283185307 );
-
- double random = 0.0;
- if (target_time == 0.0) {
- strength = random = 1 - 2.0*(double(rand())/double(RAND_MAX));
- target_time = time + 0.71 + (random * 0.5);
- }
- if (time > target_time) {
- spike = 1.0;
- target_time = 0.0;
- }
-
- // max vertical wind speed in fps, corresponds to TurbGain = 1.0
- double max_vs = 40;
-
- vTurbulenceNED(1) = vTurbulenceNED(2) = vTurbulenceNED(3) = 0.0;
- double delta = strength * max_vs * TurbGain * (1-Rhythmicity) * spike;
-
- // Vertical component of turbulence.
- vTurbulenceNED(3) = sinewave * max_vs * TurbGain * Rhythmicity;
- vTurbulenceNED(3)+= delta;
- double HOverBMAC = Auxiliary->GetHOverBMAC();
- if (HOverBMAC < 3.0)
- vTurbulenceNED(3) *= HOverBMAC * 0.3333;
-
- // Yaw component of turbulence.
- vTurbulenceNED(1) = sin( delta * 3.0 );
- vTurbulenceNED(2) = cos( delta * 3.0 );
-
- // Roll component of turbulence. Clockwise vortex causes left roll.
- vTurbPQR(eP) += delta * 0.04;
-
- spike = spike * 0.9;
+ case eRankine:
+ targetTemp = t;
+ break;
+ case eKelvin:
+ targetTemp = t*9.0/5.0;
break;
- }
- case ttMilspec:
- case ttTustin: {
- // an index of zero means turbulence is disabled
- if (probability_of_exceedence_index == 0) {
- vTurbulenceNED(1) = vTurbulenceNED(2) = vTurbulenceNED(3) = 0.0;
- vTurbPQR(1) = vTurbPQR(2) = vTurbPQR(3) = 0.0;
- return;
- }
-
- // Turbulence model according to MIL-F-8785C (Flying Qualities of Piloted Aircraft)
- double
- h = Propagate->GetDistanceAGL(),
- V = Auxiliary->GetVt(), // true airspeed in ft/s
- b_w = Aircraft->GetWingSpan(),
- L_u, L_w, sig_u, sig_w;
-
- // clip height functions at 10 ft
- if (h <= 10.) h = 10;
-
- // Scale lengths L and amplitudes sigma as function of height
- if (h <= 1000) {
- L_u = h/pow(0.177 + 0.000823*h, 1.2); // MIL-F-8785c, Fig. 10, p. 55
- L_w = h;
- sig_w = 0.1*windspeed_at_20ft;
- sig_u = sig_w/pow(0.177 + 0.000823*h, 0.4); // MIL-F-8785c, Fig. 11, p. 56
- } else if (h <= 2000) {
- // linear interpolation between low altitude and high altitude models
- L_u = L_w = 1000 + (h-1000.)/1000.*750.;
- sig_u = sig_w = 0.1*windspeed_at_20ft
- + (h-1000.)/1000.*(POE_Table->GetValue(probability_of_exceedence_index, h) - 0.1*windspeed_at_20ft);
- } else {
- L_u = L_w = 1750.; // MIL-F-8785c, Sec. 3.7.2.1, p. 48
- sig_u = sig_w = POE_Table->GetValue(probability_of_exceedence_index, h);
- }
-
- // keep values from last timesteps
- // TODO maybe use deque?
- static double
- xi_u_km1 = 0, nu_u_km1 = 0,
- xi_v_km1 = 0, xi_v_km2 = 0, nu_v_km1 = 0, nu_v_km2 = 0,
- xi_w_km1 = 0, xi_w_km2 = 0, nu_w_km1 = 0, nu_w_km2 = 0,
- xi_p_km1 = 0, nu_p_km1 = 0,
- xi_q_km1 = 0, xi_r_km1 = 0;
-
-
- double
- T_V = DeltaT, // for compatibility of nomenclature
- sig_p = 1.9/sqrt(L_w*b_w)*sig_w, // Yeager1998, eq. (8)
- sig_q = sqrt(M_PI/2/L_w/b_w), // eq. (14)
- sig_r = sqrt(2*M_PI/3/L_w/b_w), // eq. (17)
- L_p = sqrt(L_w*b_w)/2.6, // eq. (10)
- tau_u = L_u/V, // eq. (6)
- tau_w = L_w/V, // eq. (3)
- tau_p = L_p/V, // eq. (9)
- tau_q = 4*b_w/M_PI/V, // eq. (13)
- tau_r =3*b_w/M_PI/V, // eq. (17)
- nu_u = GaussianRandomNumber(),
- nu_v = GaussianRandomNumber(),
- nu_w = GaussianRandomNumber(),
- nu_p = GaussianRandomNumber(),
- xi_u, xi_v, xi_w, xi_p, xi_q, xi_r;
-
- // values of turbulence NED velocities
-
- if (turbType == ttTustin) {
- // the following is the Tustin formulation of Yeager's report
- double
- omega_w = V/L_w, // hidden in nomenclature p. 3
- omega_v = V/L_u, // this is defined nowhere
- C_BL = 1/tau_u/tan(T_V/2/tau_u), // eq. (19)
- C_BLp = 1/tau_p/tan(T_V/2/tau_p), // eq. (22)
- C_BLq = 1/tau_q/tan(T_V/2/tau_q), // eq. (24)
- C_BLr = 1/tau_r/tan(T_V/2/tau_r); // eq. (26)
-
- xi_u = -(1 - C_BL*tau_u)/(1 + C_BL*tau_u)*xi_u_km1
- + sig_u*sqrt(2*tau_u/T_V)/(1 + C_BL*tau_u)*(nu_u + nu_u_km1); // eq. (18)
- xi_v = -2*(sqr(omega_v) - sqr(C_BL))/sqr(omega_v + C_BL)*xi_v_km1
- - sqr(omega_v - C_BL)/sqr(omega_v + C_BL) * xi_v_km2
- + sig_u*sqrt(3*omega_v/T_V)/sqr(omega_v + C_BL)*(
- (C_BL + omega_v/sqrt(3.))*nu_v
- + 2/sqrt(3.)*omega_v*nu_v_km1
- + (omega_v/sqrt(3.) - C_BL)*nu_v_km2); // eq. (20) for v
- xi_w = -2*(sqr(omega_w) - sqr(C_BL))/sqr(omega_w + C_BL)*xi_w_km1
- - sqr(omega_w - C_BL)/sqr(omega_w + C_BL) * xi_w_km2
- + sig_w*sqrt(3*omega_w/T_V)/sqr(omega_w + C_BL)*(
- (C_BL + omega_w/sqrt(3.))*nu_w
- + 2/sqrt(3.)*omega_w*nu_w_km1
- + (omega_w/sqrt(3.) - C_BL)*nu_w_km2); // eq. (20) for w
- xi_p = -(1 - C_BLp*tau_p)/(1 + C_BLp*tau_p)*xi_p_km1
- + sig_p*sqrt(2*tau_p/T_V)/(1 + C_BLp*tau_p) * (nu_p + nu_p_km1); // eq. (21)
- xi_q = -(1 - 4*b_w*C_BLq/M_PI/V)/(1 + 4*b_w*C_BLq/M_PI/V) * xi_q_km1
- + C_BLq/V/(1 + 4*b_w*C_BLq/M_PI/V) * (xi_w - xi_w_km1); // eq. (23)
- xi_r = - (1 - 3*b_w*C_BLr/M_PI/V)/(1 + 3*b_w*C_BLr/M_PI/V) * xi_r_km1
- + C_BLr/V/(1 + 3*b_w*C_BLr/M_PI/V) * (xi_v - xi_v_km1); // eq. (25)
-
- } else if (turbType == ttMilspec) {
- // the following is the MIL-STD-1797A formulation
- // as cited in Yeager's report
- xi_u = (1 - T_V/tau_u) *xi_u_km1 + sig_u*sqrt(2*T_V/tau_u)*nu_u; // eq. (30)
- xi_v = (1 - 2*T_V/tau_u)*xi_v_km1 + sig_u*sqrt(4*T_V/tau_u)*nu_v; // eq. (31)
- xi_w = (1 - 2*T_V/tau_w)*xi_w_km1 + sig_w*sqrt(4*T_V/tau_w)*nu_w; // eq. (32)
- xi_p = (1 - T_V/tau_p) *xi_p_km1 + sig_p*sqrt(2*T_V/tau_p)*nu_p; // eq. (33)
- xi_q = (1 - T_V/tau_q) *xi_q_km1 + M_PI/4/b_w*(xi_w - xi_w_km1); // eq. (34)
- xi_r = (1 - T_V/tau_r) *xi_r_km1 + M_PI/3/b_w*(xi_v - xi_v_km1); // eq. (35)
- }
-
- // rotate by wind azimuth and assign the velocities
- double cospsi = cos(psiw), sinpsi = sin(psiw);
- vTurbulenceNED(1) = cospsi*xi_u + sinpsi*xi_v;
- vTurbulenceNED(2) = -sinpsi*xi_u + cospsi*xi_v;
- vTurbulenceNED(3) = xi_w;
-
- vTurbPQR(1) = cospsi*xi_p + sinpsi*xi_q;
- vTurbPQR(2) = -sinpsi*xi_p + cospsi*xi_q;
- vTurbPQR(3) = xi_r;
-
- // vTurbPQR is in the body fixed frame, not NED
- vTurbPQR = Propagate->GetTl2b()*vTurbPQR;
-
- // hand on the values for the next timestep
- xi_u_km1 = xi_u; nu_u_km1 = nu_u;
- xi_v_km2 = xi_v_km1; xi_v_km1 = xi_v; nu_v_km2 = nu_v_km1; nu_v_km1 = nu_v;
- xi_w_km2 = xi_w_km1; xi_w_km1 = xi_w; nu_w_km2 = nu_w_km1; nu_w_km1 = nu_w;
- xi_p_km1 = xi_p; nu_p_km1 = nu_p;
- xi_q_km1 = xi_q;
- xi_r_km1 = xi_r;
-
- }
default:
break;
}
+
+ return targetTemp;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-void FGAtmosphere::UseExternal(void)
+double FGAtmosphere::ConvertToPSF(double p, ePressure unit) const
{
- temperature=&exTemperature;
- pressure=&exPressure;
- density=&exDensity;
- useExternal=true;
-}
+ double targetPressure=0; // Pressure in PSF
-//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ switch(unit) {
+ case ePSF:
+ targetPressure = p;
+ break;
+ case eMillibars:
+ targetPressure = p*2.08854342;
+ break;
+ case ePascals:
+ targetPressure = p*0.0208854342;
+ break;
+ case eInchesHg:
+ targetPressure = p*70.7180803;
+ break;
+ default:
+ throw("Undefined pressure unit given");
+ }
-void FGAtmosphere::UseInternal(void)
-{
- temperature=&intTemperature;
- pressure=&intPressure;
- density=&intDensity;
- useExternal=false;
+ return targetPressure;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void FGAtmosphere::bind(void)
{
- typedef double (FGAtmosphere::*PMF)(int) const;
- typedef double (FGAtmosphere::*PMFv)(void) const;
- typedef int (FGAtmosphere::*PMFt)(void) const;
- typedef void (FGAtmosphere::*PMFd)(int,double);
- typedef void (FGAtmosphere::*PMFi)(int);
- PropertyManager->Tie("atmosphere/T-R", this, (PMFv)&FGAtmosphere::GetTemperature);
- PropertyManager->Tie("atmosphere/rho-slugs_ft3", this, (PMFv)&FGAtmosphere::GetDensity);
- PropertyManager->Tie("atmosphere/P-psf", this, (PMFv)&FGAtmosphere::GetPressure);
+ typedef double (FGAtmosphere::*PMFi)(int) const;
+ typedef void (FGAtmosphere::*PMF)(int, double);
+ PropertyManager->Tie("atmosphere/T-R", this, &FGAtmosphere::GetTemperature);
+ PropertyManager->Tie("atmosphere/rho-slugs_ft3", this, &FGAtmosphere::GetDensity);
+ PropertyManager->Tie("atmosphere/P-psf", this, &FGAtmosphere::GetPressure);
PropertyManager->Tie("atmosphere/a-fps", this, &FGAtmosphere::GetSoundSpeed);
PropertyManager->Tie("atmosphere/T-sl-R", this, &FGAtmosphere::GetTemperatureSL);
PropertyManager->Tie("atmosphere/rho-sl-slugs_ft3", this, &FGAtmosphere::GetDensitySL);
- PropertyManager->Tie("atmosphere/P-sl-psf", this, &FGAtmosphere::GetPressureSL);
+// PropertyManager->Tie("atmosphere/P-sl-psf", this, ePSF,
+// (PMFi)&FGAtmosphere::GetPressureSL,
+// (PMF)&FGAtmosphere::SetPressureSL);
PropertyManager->Tie("atmosphere/a-sl-fps", this, &FGAtmosphere::GetSoundSpeedSL);
PropertyManager->Tie("atmosphere/theta", this, &FGAtmosphere::GetTemperatureRatio);
PropertyManager->Tie("atmosphere/sigma", this, &FGAtmosphere::GetDensityRatio);
PropertyManager->Tie("atmosphere/delta", this, &FGAtmosphere::GetPressureRatio);
PropertyManager->Tie("atmosphere/a-ratio", this, &FGAtmosphere::GetSoundSpeedRatio);
- PropertyManager->Tie("atmosphere/psiw-rad", this, &FGAtmosphere::GetWindPsi, &FGAtmosphere::SetWindPsi);
- PropertyManager->Tie("atmosphere/delta-T", this, &FGAtmosphere::GetDeltaT, &FGAtmosphere::SetDeltaT);
- PropertyManager->Tie("atmosphere/T-sl-dev-F", this, &FGAtmosphere::GetSLTempDev, &FGAtmosphere::SetSLTempDev);
PropertyManager->Tie("atmosphere/density-altitude", this, &FGAtmosphere::GetDensityAltitude);
-
- PropertyManager->Tie("atmosphere/wind-north-fps", this, eNorth, (PMF)&FGAtmosphere::GetWindNED,
- (PMFd)&FGAtmosphere::SetWindNED);
- PropertyManager->Tie("atmosphere/wind-east-fps", this, eEast, (PMF)&FGAtmosphere::GetWindNED,
- (PMFd)&FGAtmosphere::SetWindNED);
- PropertyManager->Tie("atmosphere/wind-down-fps", this, eDown, (PMF)&FGAtmosphere::GetWindNED,
- (PMFd)&FGAtmosphere::SetWindNED);
- PropertyManager->Tie("atmosphere/wind-mag-fps", this, &FGAtmosphere::GetWindspeed,
- &FGAtmosphere::SetWindspeed);
- PropertyManager->Tie("atmosphere/total-wind-north-fps", this, eNorth, (PMF)&FGAtmosphere::GetTotalWindNED);
- PropertyManager->Tie("atmosphere/total-wind-east-fps", this, eEast, (PMF)&FGAtmosphere::GetTotalWindNED);
- PropertyManager->Tie("atmosphere/total-wind-down-fps", this, eDown, (PMF)&FGAtmosphere::GetTotalWindNED);
-
- PropertyManager->Tie("atmosphere/gust-north-fps", this, eNorth, (PMF)&FGAtmosphere::GetGustNED,
- (PMFd)&FGAtmosphere::SetGustNED);
- PropertyManager->Tie("atmosphere/gust-east-fps", this, eEast, (PMF)&FGAtmosphere::GetGustNED,
- (PMFd)&FGAtmosphere::SetGustNED);
- PropertyManager->Tie("atmosphere/gust-down-fps", this, eDown, (PMF)&FGAtmosphere::GetGustNED,
- (PMFd)&FGAtmosphere::SetGustNED);
-
- PropertyManager->Tie("atmosphere/turb-north-fps", this, eNorth, (PMF)&FGAtmosphere::GetTurbNED,
- (PMFd)&FGAtmosphere::SetTurbNED);
- PropertyManager->Tie("atmosphere/turb-east-fps", this, eEast, (PMF)&FGAtmosphere::GetTurbNED,
- (PMFd)&FGAtmosphere::SetTurbNED);
- PropertyManager->Tie("atmosphere/turb-down-fps", this, eDown, (PMF)&FGAtmosphere::GetTurbNED,
- (PMFd)&FGAtmosphere::SetTurbNED);
-
- PropertyManager->Tie("atmosphere/p-turb-rad_sec", this,1, (PMF)&FGAtmosphere::GetTurbPQR);
- PropertyManager->Tie("atmosphere/q-turb-rad_sec", this,2, (PMF)&FGAtmosphere::GetTurbPQR);
- PropertyManager->Tie("atmosphere/r-turb-rad_sec", this,3, (PMF)&FGAtmosphere::GetTurbPQR);
- PropertyManager->Tie("atmosphere/turb-type", this, (PMFt)&FGAtmosphere::GetTurbType, (PMFi)&FGAtmosphere::SetTurbType);
- PropertyManager->Tie("atmosphere/turb-rate", this, &FGAtmosphere::GetTurbRate, &FGAtmosphere::SetTurbRate);
- PropertyManager->Tie("atmosphere/turb-gain", this, &FGAtmosphere::GetTurbGain, &FGAtmosphere::SetTurbGain);
- PropertyManager->Tie("atmosphere/turb-rhythmicity", this, &FGAtmosphere::GetRhythmicity,
- &FGAtmosphere::SetRhythmicity);
-
- PropertyManager->Tie("atmosphere/turbulence/milspec/windspeed_at_20ft_AGL-fps",
- this, &FGAtmosphere::GetWindspeed20ft,
- &FGAtmosphere::SetWindspeed20ft);
- PropertyManager->Tie("atmosphere/turbulence/milspec/severity",
- this, &FGAtmosphere::GetProbabilityOfExceedence,
- &FGAtmosphere::SetProbabilityOfExceedence);
-
+ PropertyManager->Tie("atmosphere/pressure-altitude", this, &FGAtmosphere::GetPressureAltitude);
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
}
}
if (debug_lvl & 2 ) { // Instantiation/Destruction notification
- if (from == 0) cout << "Instantiated: FGAtmosphere" << endl;
- if (from == 1) cout << "Destroyed: FGAtmosphere" << endl;
+ if (from == 0) std::cout << "Instantiated: FGAtmosphere" << std::endl;
+ if (from == 1) std::cout << "Destroyed: FGAtmosphere" << std::endl;
}
if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
}
}
if (debug_lvl & 16) { // Sanity checking
}
- if (debug_lvl & 128) { // Turbulence
- if (first_pass && from == 2) {
- first_pass = false;
- cout << "vTurbulenceNED(X), vTurbulenceNED(Y), vTurbulenceNED(Z), "
- << "vTurbulenceGrad(X), vTurbulenceGrad(Y), vTurbulenceGrad(Z), "
- << "vDirection(X), vDirection(Y), vDirection(Z), "
- << "Magnitude, "
- << "vTurbPQR(P), vTurbPQR(Q), vTurbPQR(R), " << endl;
- }
- if (from == 2) {
- cout << vTurbulenceNED << ", " << vTurbulenceGrad << ", " << vDirection << ", " << Magnitude << ", " << vTurbPQR << endl;
- }
+ if (debug_lvl & 128) { //
}
if (debug_lvl & 64) {
if (from == 0) { // Constructor
- cout << IdSrc << endl;
- cout << IdHdr << endl;
+ std::cout << IdSrc << std::endl;
+ std::cout << IdHdr << std::endl;
}
}
}
projects / flightgear.git / blobdiff