JSBSim Flight Dynamics Model  1.0 (02 March 2017)
An Open Source Flight Dynamics and Control Software Library in C++
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 (jon@jsbsim.org) -------------
9 
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
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 Lesser General Public License for more
18  details.
19 
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.
23 
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.
26 
27 FUNCTIONAL DESCRIPTION
28 --------------------------------------------------------------------------------
29 
30 HISTORY
31 --------------------------------------------------------------------------------
32 08/24/00 JSB Created
33 
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35 INCLUDES
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
37 
38 #include <iostream>
39 #include <sstream>
40 #include <cstdlib>
41 
42 #include "FGNozzle.h"
43 #include "input_output/FGXMLElement.h"
44 
45 using namespace std;
46 
47 namespace JSBSim {
48 
49 IDENT(IdSrc,"$Id: FGNozzle.cpp,v 1.17 2014/01/13 10:46:10 ehofman Exp $");
50 IDENT(IdHdr,ID_NOZZLE);
51 
52 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
53 CLASS IMPLEMENTATION
54 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
55 
56 
57 FGNozzle::FGNozzle(FGFDMExec* FDMExec, Element* nozzle_element, int num)
58  : FGThruster(FDMExec, nozzle_element, num)
59 {
60  if (nozzle_element->FindElement("area"))
61  Area = nozzle_element->FindElementValueAsNumberConvertTo("area", "FT2");
62  else {
63  cerr << "Fatal Error: Nozzle exit area must be given in nozzle config file." << endl;
64  exit(-1);
65  }
66 
67  Thrust = 0;
68  Type = ttNozzle;
69 
70  Debug(0);
71 }
72 
73 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
74 
76 {
77  Debug(1);
78 }
79 
80 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
81 
82 double FGNozzle::Calculate(double vacThrust)
83 {
84  Thrust = max((double)0.0, vacThrust - in.Pressure*Area);
85 
86  vFn(1) = Thrust * cos(ReverserAngle);
87 
88  return Thrust;
89 }
90 
91 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
92 
93 string FGNozzle::GetThrusterLabels(int id, const string& delimeter)
94 {
95  std::ostringstream buf;
96 
97  buf << Name << " Thrust (engine " << id << " in lbs)";
98 
99  return buf.str();
100 }
101 
102 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
103 
104 string FGNozzle::GetThrusterValues(int id, const string& delimeter)
105 {
106  std::ostringstream buf;
107 
108  buf << Thrust;
109 
110  return buf.str();
111 }
112 
113 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
114 // The bitmasked value choices are as follows:
115 // unset: In this case (the default) JSBSim would only print
116 // out the normally expected messages, essentially echoing
117 // the config files as they are read. If the environment
118 // variable is not set, debug_lvl is set to 1 internally
119 // 0: This requests JSBSim not to output any messages
120 // whatsoever.
121 // 1: This value explicity requests the normal JSBSim
122 // startup messages
123 // 2: This value asks for a message to be printed out when
124 // a class is instantiated
125 // 4: When this value is set, a message is displayed when a
126 // FGModel object executes its Run() method
127 // 8: When this value is set, various runtime state variables
128 // are printed out periodically
129 // 16: When set various parameters are sanity checked and
130 // a message is printed out when they go out of bounds
131 
132 void FGNozzle::Debug(int from)
133 {
134  if (debug_lvl <= 0) return;
135 
136  if (debug_lvl & 1) { // Standard console startup message output
137  if (from == 0) { // Constructor
138  cout << " Nozzle Name: " << Name << endl;
139  cout << " Nozzle Exit Area = " << Area << endl;
140  }
141  }
142  if (debug_lvl & 2 ) { // Instantiation/Destruction notification
143  if (from == 0) cout << "Instantiated: FGNozzle" << endl;
144  if (from == 1) cout << "Destroyed: FGNozzle" << endl;
145  }
146  if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
147  }
148  if (debug_lvl & 8 ) { // Runtime state variables
149  }
150  if (debug_lvl & 16) { // Sanity checking
151  }
152  if (debug_lvl & 64) {
153  if (from == 0) { // Constructor
154  cout << IdSrc << endl;
155  cout << IdHdr << endl;
156  }
157  }
158 }
159 }
double FindElementValueAsNumberConvertTo(const std::string &el, const std::string &target_units)
Searches for the named element and converts and returns the data belonging to it. ...
STL namespace.
Element * FindElement(const std::string &el="")
Searches for a specified element.
Base class for specific thrusting devices such as propellers, nozzles, etc.
Definition: FGThruster.h:84
~FGNozzle()
Destructor.
Definition: FGNozzle.cpp:75
Encapsulates the JSBSim simulation executive.
Definition: FGFDMExec.h:189