1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
5 Implementation of 1959 Standard Atmosphere added by Tony Peden
8 ------------- Copyright (C) 1999 Jon S. Berndt (jsb@hal-pc.org) -------------
10 This program is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free Software
12 Foundation; either version 2 of the License, or (at your option) any later
15 This program is distributed in the hope that it will be useful, but WITHOUT
16 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
20 You should have received a copy of the GNU General Public License along with
21 this program; if not, write to the Free Software Foundation, Inc., 59 Temple
22 Place - Suite 330, Boston, MA 02111-1307, USA.
24 Further information about the GNU General Public License can also be found on
25 the world wide web at http://www.gnu.org.
28 --------------------------------------------------------------------------------
30 07/23/99 TP Added implementation of 1959 Standard Atmosphere
31 Moved calculation of Mach number to FGTranslation
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
38 #ifndef FGAtmosphere_H
39 #define FGAtmosphere_H
41 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
43 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
46 #include "FGMatrix33.h"
47 #include "FGColumnVector3.h"
48 #include "FGColumnVector4.h"
50 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
52 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
54 #define ID_ATMOSPHERE "$Id$"
56 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
58 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
62 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
64 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
66 /** Models the standard atmosphere.
67 @author Tony Peden, Jon Berndt
69 @see Anderson, John D. "Introduction to Flight, Third Edition", McGraw-Hill,
70 1989, ISBN 0-07-001641-0
73 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
75 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
77 class FGAtmosphere : public FGModel {
81 FGAtmosphere(FGFDMExec*);
84 /** Runs the Atmosphere model; called by the Executive
85 @return false if no error */
90 /// Returns the temperature in degrees Rankine.
91 inline double GetTemperature(void) const {return *temperature;}
92 /** Returns the density in slugs/ft^3.
93 <i>This function may <b>only</b> be used if Run() is called first.</i> */
94 inline double GetDensity(void) const {return *density;}
95 /// Returns the pressure in psf.
96 inline double GetPressure(void) const {return *pressure;}
97 /// Returns the speed of sound in ft/sec.
98 inline double GetSoundSpeed(void) const {return soundspeed;}
100 /// Returns the sea level temperature in degrees Rankine.
101 inline double GetTemperatureSL(void) const { return SLtemperature; }
102 /// Returns the sea level density in slugs/ft^3
103 inline double GetDensitySL(void) const { return SLdensity; }
104 /// Returns the sea level pressure in psf.
105 inline double GetPressureSL(void) const { return SLpressure; }
106 /// Returns the sea level speed of sound in ft/sec.
107 inline double GetSoundSpeedSL(void) const { return SLsoundspeed; }
109 /// Returns the ratio of at-altitude temperature over the sea level value.
110 inline double GetTemperatureRatio(void) const { return (*temperature)*rSLtemperature; }
111 /// Returns the ratio of at-altitude density over the sea level value.
112 inline double GetDensityRatio(void) const { return (*density)*rSLdensity; }
113 /// Returns the ratio of at-altitude pressure over the sea level value.
114 inline double GetPressureRatio(void) const { return (*pressure)*rSLpressure; }
115 /// Returns the ratio of at-altitude sound speed over the sea level value.
116 inline double GetSoundSpeedRatio(void) const { return soundspeed*rSLsoundspeed; }
118 /// Tells the simulator to use an externally calculated atmosphere model.
119 void UseExternal(void);
120 /// Tells the simulator to use the internal atmosphere model.
121 void UseInternal(void); //this is the default
122 /// Gets the boolean that tells if the external atmosphere model is being used.
123 bool External(void) { return useExternal; }
125 /// Provides the external atmosphere model with an interface to set the temperature.
126 inline void SetExTemperature(double t) { exTemperature=t; }
127 /// Provides the external atmosphere model with an interface to set the density.
128 inline void SetExDensity(double d) { exDensity=d; }
129 /// Provides the external atmosphere model with an interface to set the pressure.
130 inline void SetExPressure(double p) { exPressure=p; }
132 /// Sets the wind components in NED frame.
133 inline void SetWindNED(double wN, double wE, double wD) { vWindNED(1)=wN; vWindNED(2)=wE; vWindNED(3)=wD;}
135 /// Retrieves the wind components in NED frame.
136 inline FGColumnVector3& GetWindNED(void) { return vWindNED; }
138 /** Retrieves the wind direction. The direction is defined as north=0 and
139 increases counterclockwise. The wind heading is returned in radians.*/
140 inline double GetWindPsi(void) const { return psiw; }
142 inline void SetTurbGain(double tt) {TurbGain = tt;}
143 inline void SetTurbRate(double tt) {TurbRate = tt;}
145 inline double GetTurbPQR(int idx) const {return vTurbPQR(idx);}
146 inline FGColumnVector3& GetTurbPQR(void) {return vTurbPQR;}
155 enum tType {ttStandard, ttBerndt, ttNone} turbType;
160 double SLtemperature,SLdensity,SLpressure,SLsoundspeed;
161 double rSLtemperature,rSLdensity,rSLpressure,rSLsoundspeed; //reciprocals
162 double *temperature,*density,*pressure;
165 double exTemperature,exDensity,exPressure;
166 double intTemperature, intDensity, intPressure;
168 double MagnitudedAccelDt, MagnitudeAccel, Magnitude;
171 FGColumnVector3 vDirectiondAccelDt;
172 FGColumnVector3 vDirectionAccel;
173 FGColumnVector3 vDirection;
174 FGColumnVector3 vTurbulence;
175 FGColumnVector3 vTurbulenceGrad;
176 FGColumnVector3 vBodyTurbGrad;
177 FGColumnVector3 vTurbPQR;
179 FGColumnVector3 vWindNED;
182 void Calculate(double altitude);
183 void Turbulence(void);
184 void Debug(int from);
187 } // namespace JSBSim
189 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%