1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
6 Purpose: Encapsulates the nozzle object
8 ------------- Copyright (C) 2000 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.
27 FUNCTIONAL DESCRIPTION
28 --------------------------------------------------------------------------------
31 --------------------------------------------------------------------------------
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
41 #include "FGAtmosphere.h"
45 static const char *IdSrc = "$Id$";
46 static const char *IdHdr = ID_NOZZLE;
48 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
50 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
53 FGNozzle::FGNozzle(FGFDMExec* FDMExec, FGConfigFile* Nzl_cfg, int num) : FGThruster(FDMExec)
57 Name = Nzl_cfg->GetValue("NAME");
58 Nzl_cfg->GetNextConfigLine();
59 while (Nzl_cfg->GetValue() != string("/FG_NOZZLE")) {
61 if (token == "PE") *Nzl_cfg >> PE;
62 else if (token == "EXPR") *Nzl_cfg >> ExpR;
63 else if (token == "NZL_EFF") *Nzl_cfg >> nzlEff;
64 else if (token == "DIAM") *Nzl_cfg >> Diameter;
65 else cerr << "Unhandled token in Nozzle config file: " << token << endl;
71 Area2 = (Diameter*Diameter/4.0)*M_PI;
74 char property_name[80];
75 snprintf(property_name, 80, "propulsion/c-thrust[%u]", EngineNum);
76 PropertyManager->Tie( property_name, &ThrustCoeff );
81 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
85 char property_name[80];
86 snprintf(property_name, 80, "propulsion/c-thrust[%u]", EngineNum);
87 PropertyManager->Untie( property_name );
92 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
94 double FGNozzle::Calculate(double CfPc)
96 double pAtm = fdmex->GetAtmosphere()->GetPressure();
97 Thrust = max((double)0.0, (CfPc * AreaT + (PE - pAtm)*Area2) * nzlEff);
98 vFn(1) = Thrust * cos(ReverserAngle);
100 ThrustCoeff = max((double)0.0, CfPc / ((pAtm - PE) * Area2));
105 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
107 double FGNozzle::GetPowerRequired(void)
112 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
114 string FGNozzle::GetThrusterLabels(int id)
116 std::ostringstream buf;
118 buf << Name << "_Thrust[" << id << ']';
123 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
125 string FGNozzle::GetThrusterValues(int id)
127 std::ostringstream buf;
134 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
135 // The bitmasked value choices are as follows:
136 // unset: In this case (the default) JSBSim would only print
137 // out the normally expected messages, essentially echoing
138 // the config files as they are read. If the environment
139 // variable is not set, debug_lvl is set to 1 internally
140 // 0: This requests JSBSim not to output any messages
142 // 1: This value explicity requests the normal JSBSim
144 // 2: This value asks for a message to be printed out when
145 // a class is instantiated
146 // 4: When this value is set, a message is displayed when a
147 // FGModel object executes its Run() method
148 // 8: When this value is set, various runtime state variables
149 // are printed out periodically
150 // 16: When set various parameters are sanity checked and
151 // a message is printed out when they go out of bounds
153 void FGNozzle::Debug(int from)
155 if (debug_lvl <= 0) return;
157 if (debug_lvl & 1) { // Standard console startup message output
158 if (from == 0) { // Constructor
159 cout << " Nozzle Name: " << Name << endl;
160 cout << " Nozzle Exit Pressure = " << PE << endl;
161 cout << " Nozzle Expansion Ratio = " << ExpR << endl;
162 cout << " Nozzle Efficiency = " << nzlEff << endl;
163 cout << " Nozzle Diameter = " << Diameter << endl;
166 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
167 if (from == 0) cout << "Instantiated: FGNozzle" << endl;
168 if (from == 1) cout << "Destroyed: FGNozzle" << endl;
170 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
172 if (debug_lvl & 8 ) { // Runtime state variables
174 if (debug_lvl & 16) { // Sanity checking
176 if (debug_lvl & 64) {
177 if (from == 0) { // Constructor
178 cout << IdSrc << endl;
179 cout << IdHdr << endl;