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;
70 Area2 = (Diameter*Diameter/4.0)*M_PI;
73 char property_name[80];
74 snprintf(property_name, 80, "propulsion/c-thrust[%u]", EngineNum);
75 PropertyManager->Tie( property_name, &ThrustCoeff );
80 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
84 char property_name[80];
85 snprintf(property_name, 80, "propulsion/c-thrust[%u]", EngineNum);
86 PropertyManager->Untie( property_name );
91 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
93 double FGNozzle::Calculate(double CfPc)
95 double pAtm = fdmex->GetAtmosphere()->GetPressure();
96 Thrust = max((double)0.0, (CfPc * AreaT + (PE - pAtm)*Area2) * nzlEff);
99 ThrustCoeff = max((double)0.0, CfPc / ((pAtm - PE) * Area2));
104 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
106 double FGNozzle::GetPowerRequired(void)
111 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
113 string FGNozzle::GetThrusterLabels(int id, string delimeter)
115 std::ostringstream buf;
117 buf << Name << "_Thrust[" << id << ']';
122 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
124 string FGNozzle::GetThrusterValues(int id, string delimeter)
126 std::ostringstream buf;
133 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
134 // The bitmasked value choices are as follows:
135 // unset: In this case (the default) JSBSim would only print
136 // out the normally expected messages, essentially echoing
137 // the config files as they are read. If the environment
138 // variable is not set, debug_lvl is set to 1 internally
139 // 0: This requests JSBSim not to output any messages
141 // 1: This value explicity requests the normal JSBSim
143 // 2: This value asks for a message to be printed out when
144 // a class is instantiated
145 // 4: When this value is set, a message is displayed when a
146 // FGModel object executes its Run() method
147 // 8: When this value is set, various runtime state variables
148 // are printed out periodically
149 // 16: When set various parameters are sanity checked and
150 // a message is printed out when they go out of bounds
152 void FGNozzle::Debug(int from)
154 if (debug_lvl <= 0) return;
156 if (debug_lvl & 1) { // Standard console startup message output
157 if (from == 0) { // Constructor
158 cout << " Nozzle Name: " << Name << endl;
159 cout << " Nozzle Exit Pressure = " << PE << endl;
160 cout << " Nozzle Expansion Ratio = " << ExpR << endl;
161 cout << " Nozzle Efficiency = " << nzlEff << endl;
162 cout << " Nozzle Diameter = " << Diameter << endl;
165 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
166 if (from == 0) cout << "Instantiated: FGNozzle" << endl;
167 if (from == 1) cout << "Destroyed: FGNozzle" << endl;
169 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
171 if (debug_lvl & 8 ) { // Runtime state variables
173 if (debug_lvl & 16) { // Sanity checking
175 if (debug_lvl & 64) {
176 if (from == 0) { // Constructor
177 cout << IdSrc << endl;
178 cout << IdHdr << endl;