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 Lesser 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 Lesser General Public License for more
20 You should have received a copy of the GNU Lesser 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 Lesser 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 <models/FGAtmosphere.h>
45 static const char *IdSrc = "$Id$";
46 static const char *IdHdr = ID_NOZZLE;
48 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
50 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
53 FGNozzle::FGNozzle(FGFDMExec* FDMExec, Element* nozzle_element, int num)
54 : FGThruster(FDMExec, nozzle_element, num)
57 if (nozzle_element->FindElement("pe"))
58 PE = nozzle_element->FindElementValueAsNumberConvertTo("pe", "PSF");
60 cerr << "Fatal Error: Nozzle exit pressure must be given in nozzle config file." << endl;
63 if (nozzle_element->FindElement("expr"))
64 ExpR = nozzle_element->FindElementValueAsNumber("expr");
66 cerr << "Fatal Error: Nozzle expansion ratio must be given in nozzle config file." << endl;
69 if (nozzle_element->FindElement("nzl_eff"))
70 nzlEff = nozzle_element->FindElementValueAsNumber("nzl_eff");
72 cerr << "Fatal Error: Nozzle efficiency must be given in nozzle config file." << endl;
75 if (nozzle_element->FindElement("diam"))
76 Diameter = nozzle_element->FindElementValueAsNumberConvertTo("diam", "FT");
78 cerr << "Fatal Error: Nozzle diameter must be given in nozzle config file." << endl;
84 Area2 = (Diameter*Diameter/4.0)*M_PI;
90 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
97 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
99 double FGNozzle::Calculate(double CfPc)
101 double pAtm = fdmex->GetAtmosphere()->GetPressure();
103 Thrust = max((double)0.0, (CfPc * AreaT + (PE - pAtm)*Area2) * nzlEff);
107 vFn(1) = Thrust * cos(ReverserAngle);
109 ThrustCoeff = max((double)0.0, CfPc / ((pAtm - PE) * Area2));
114 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
116 double FGNozzle::GetPowerRequired(void)
121 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
123 string FGNozzle::GetThrusterLabels(int id, string delimeter)
125 std::ostringstream buf;
127 buf << Name << " Thrust (engine " << id << " in lbs)";
132 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
134 string FGNozzle::GetThrusterValues(int id, string delimeter)
136 std::ostringstream buf;
143 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
144 // The bitmasked value choices are as follows:
145 // unset: In this case (the default) JSBSim would only print
146 // out the normally expected messages, essentially echoing
147 // the config files as they are read. If the environment
148 // variable is not set, debug_lvl is set to 1 internally
149 // 0: This requests JSBSim not to output any messages
151 // 1: This value explicity requests the normal JSBSim
153 // 2: This value asks for a message to be printed out when
154 // a class is instantiated
155 // 4: When this value is set, a message is displayed when a
156 // FGModel object executes its Run() method
157 // 8: When this value is set, various runtime state variables
158 // are printed out periodically
159 // 16: When set various parameters are sanity checked and
160 // a message is printed out when they go out of bounds
162 void FGNozzle::Debug(int from)
164 if (debug_lvl <= 0) return;
166 if (debug_lvl & 1) { // Standard console startup message output
167 if (from == 0) { // Constructor
168 cout << " Nozzle Name: " << Name << endl;
169 cout << " Nozzle Exit Pressure = " << PE << endl;
170 cout << " Nozzle Expansion Ratio = " << ExpR << endl;
171 cout << " Nozzle Efficiency = " << nzlEff << endl;
172 cout << " Nozzle Diameter = " << Diameter << endl;
175 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
176 if (from == 0) cout << "Instantiated: FGNozzle" << endl;
177 if (from == 1) cout << "Destroyed: FGNozzle" << endl;
179 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
181 if (debug_lvl & 8 ) { // Runtime state variables
183 if (debug_lvl & 16) { // Sanity checking
185 if (debug_lvl & 64) {
186 if (from == 0) { // Constructor
187 cout << IdSrc << endl;
188 cout << IdHdr << endl;