src/FDM/JSBSim/FGNozzle.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGNozzle.cpp
   4  Author:       Jon S. Berndt
   5  Date started: 08/24/00
   6  Purpose:      Encapsulates the nozzle object
   7
   8  ------------- Copyright (C) 2000  Jon S. Berndt (jsb@hal-pc.org) -------------
   9
  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
  13  version.
  14
  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
  18  details.
  19
  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.
  23
  24  Further information about the GNU General Public License can also be found on
  25  the world wide web at http://www.gnu.org.
  26
  27 FUNCTIONAL DESCRIPTION
  28 --------------------------------------------------------------------------------
  29
  30 HISTORY
  31 --------------------------------------------------------------------------------
  32 08/24/00  JSB  Created
  33
  34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  35 INCLUDES
  36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  37
  38 #include "FGNozzle.h"
  39
  40 static const char *IdSrc = "$Id$";
  41 static const char *IdHdr = ID_NOZZLE;
  42
  43 extern short debug_lvl;
  44
  45 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  46 CLASS IMPLEMENTATION
  47 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  48
  49
  50 FGNozzle::FGNozzle(FGFDMExec* FDMExec, FGConfigFile* Nzl_cfg) : FGThruster(FDMExec)
  51 {
  52   string token;
  53
  54   Name = Nzl_cfg->GetValue("NAME");
  55   cout << "      Nozzle Name: " << Name << endl;
  56   Nzl_cfg->GetNextConfigLine();
  57   while (Nzl_cfg->GetValue() != "/FG_NOZZLE") {
  58     *Nzl_cfg >> token;
  59     if (token == "PE") {
  60       *Nzl_cfg >> PE;
  61       cout << "      Nozzle Exit Pressure = " << PE << endl;
  62     } else if (token == "EXPR") {
  63       *Nzl_cfg >> ExpR;
  64       cout << "      Nozzle Expansion Ratio = " << ExpR << endl;
  65     } else if (token == "NZL_EFF") {
  66       *Nzl_cfg >> nzlEff;
  67       cout << "      Nozzle Efficiency = " << nzlEff << endl;
  68     } else if (token == "DIAM") {
  69       *Nzl_cfg >> Diameter;
  70       cout << "      Nozzle Diameter = " << Diameter << endl;
  71     } else {
  72       cout << "Unhandled token in Nozzle config file: " << token << endl;
  73     }
  74   }
  75
  76   if (debug_lvl & 2) cout << "Instantiated: FGNozzle" << endl;
  77 }
  78
  79 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  80
  81 FGNozzle::~FGNozzle()
  82 {
  83   if (debug_lvl & 2) cout << "Destroyed:    FGNozzle" << endl;
  84 }
  85
  86 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  87
  88 float FGNozzle::Calculate(float CfPc)
  89 {
  90   float Thrust;
  91   float pAtm = fdmex->GetAtmosphere()->GetPressure();
  92
  93   Thrust = (CfPc + (PE - pAtm)*ExpR) * (Diameter / ExpR) * nzlEff;
  94
  95   return Thrust;
  96 }
  97
  98 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  99
 100 float FGNozzle::GetPowerRequired(void)
 101 {
 102   return PE;
 103 }
 104
 105 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 106
 107 void FGNozzle::Debug(void)
 108 {
 109     //TODO: Add your source code here
 110 }
 111