1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
8 ------------- Copyright (C) 1999 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 --------------------------------------------------------------------------------
32 --------------------------------------------------------------------------------
35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
47 static const char *IdSrc = "$Id$";
48 static const char *IdHdr = ID_TANK;
50 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
52 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
54 FGTank::FGTank(FGFDMExec* exec, Element* el, int tank_number)
55 : TankNumber(tank_number)
59 Element* element_Grain;
61 Temperature = -9999.0;
62 Ixx = Iyy = Izz = 0.0;
63 Auxiliary = exec->GetAuxiliary();
64 Radius = Capacity = Contents = Standpipe = Length = InnerRadius = 0.0;
65 PropertyManager = exec->GetPropertyManager();
67 vXYZ_drain.InitMatrix();
69 type = el->GetAttributeValue("type");
70 if (type == "FUEL") Type = ttFUEL;
71 else if (type == "OXIDIZER") Type = ttOXIDIZER;
72 else Type = ttUNKNOWN;
74 element = el->FindElement("location");
75 if (element) vXYZ = element->FindElementTripletConvertTo("IN");
76 else cerr << "No location found for this tank." << endl;
78 vXYZ_drain = vXYZ; // Set initial drain location to initial tank CG
80 element = el->FindElement("drain_location");
82 vXYZ_drain = element->FindElementTripletConvertTo("IN");
85 if (el->FindElement("radius"))
86 Radius = el->FindElementValueAsNumberConvertTo("radius", "IN");
87 if (el->FindElement("capacity"))
88 Capacity = el->FindElementValueAsNumberConvertTo("capacity", "LBS");
89 if (el->FindElement("contents"))
90 InitialContents = Contents = el->FindElementValueAsNumberConvertTo("contents", "LBS");
91 if (el->FindElement("temperature"))
92 InitialTemperature = Temperature = el->FindElementValueAsNumber("temperature");
93 if (el->FindElement("standpipe"))
94 InitialStandpipe = Standpipe = el->FindElementValueAsNumberConvertTo("standpipe", "LBS");
99 PctFull = 100.0*Contents/Capacity; // percent full; 0 to 100.0
105 // Check whether this is a solid propellant "tank". Initialize it if true.
107 grainType = gtUNKNOWN; // This is the default
109 element_Grain = el->FindElement("grain_config");
112 strGType = element_Grain->GetAttributeValue("type");
113 if (strGType == "CYLINDRICAL") grainType = gtCYLINDRICAL;
114 else if (strGType == "ENDBURNING") grainType = gtENDBURNING;
115 else cerr << "Unknown propellant grain type specified" << endl;
117 if (element_Grain->FindElement("length"))
118 Length = element_Grain->FindElementValueAsNumberConvertTo("length", "IN");
119 if (element_Grain->FindElement("bore_diameter"))
120 InnerRadius = element_Grain->FindElementValueAsNumberConvertTo("bore_diameter", "IN")/2.0;
122 // Initialize solid propellant values for debug and runtime use.
126 if (Radius <= InnerRadius) {
127 cerr << "The bore diameter should be smaller than the total grain diameter!" << endl;
130 Volume = M_PI * Length * (Radius*Radius - InnerRadius*InnerRadius); // cubic inches
133 Volume = M_PI * Length * Radius * Radius; // cubic inches
136 cerr << "Unknown grain type found in this rocket engine definition." << endl;
139 Density = (Contents*lbtoslug)/Volume; // slugs/in^3
143 string property_name, base_property_name;
144 base_property_name = CreateIndexedPropertyName("propulsion/tank", TankNumber);
145 property_name = base_property_name + "/contents-lbs";
146 PropertyManager->Tie( property_name.c_str(), (FGTank*)this, &FGTank::GetContents,
147 &FGTank::SetContents );
149 if (Temperature != -9999.0) InitialTemperature = Temperature = FahrenheitToCelsius(Temperature);
150 Area = 40.0 * pow(Capacity/1975, 0.666666667);
155 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
162 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
164 void FGTank::ResetToIC(void)
166 Temperature = InitialTemperature;
167 Standpipe = InitialStandpipe;
168 Contents = InitialContents;
169 PctFull = 100.0*Contents/Capacity;
173 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
175 const FGColumnVector3 FGTank::GetXYZ(void)
177 return vXYZ_drain + (Contents/Capacity)*(vXYZ - vXYZ_drain);
180 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
182 const double FGTank::GetXYZ(int idx)
184 return vXYZ_drain(idx) + (Contents/Capacity)*(vXYZ(idx)-vXYZ_drain(idx));
187 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
189 double FGTank::Drain(double used)
191 double remaining = Contents - used;
193 if (remaining >= 0) { // Reduce contents by amount used.
196 PctFull = 100.0*Contents/Capacity;
198 } else { // This tank must be empty.
205 if (grainType != gtUNKNOWN) CalculateInertias();
210 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
212 double FGTank::Fill(double amount)
214 double overage = 0.0;
218 if (Contents > Capacity) {
219 overage = Contents - Capacity;
223 PctFull = Contents/Capacity*100.0;
228 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
230 void FGTank::SetContents(double amount)
233 if (Contents > Capacity) {
237 PctFull = Contents/Capacity*100.0;
241 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
243 double FGTank::Calculate(double dt)
245 if (Temperature == -9999.0) return 0.0;
246 double HeatCapacity = 900.0; // Joules/lbm/C
247 double TempFlowFactor = 1.115; // Watts/sqft/C
248 double TAT = Auxiliary->GetTAT_C();
249 double Tdiff = TAT - Temperature;
250 double dTemp = 0.0; // Temp change due to one surface
251 if (fabs(Tdiff) > 0.1) {
252 dTemp = (TempFlowFactor * Area * Tdiff * dt) / (Contents * HeatCapacity);
254 return Temperature += (dTemp + dTemp); // For now, assume upper/lower the same
257 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
258 // This function calculates the moments of inertia for a solid propellant
259 // grain - either an end burning cylindrical grain or a bored cylindrical
262 void FGTank::CalculateInertias(void)
264 double Mass = Contents*lbtoslug;
266 double Rad2 = Radius*Radius;
269 Volume = (Contents*lbtoslug)/Density; // in^3
271 cerr << endl << " Solid propellant grain density is zero!" << endl << endl;
277 InnerRadius = sqrt(Rad2 - Volume/(M_PI * Length));
278 RadSumSqr = (Rad2 + InnerRadius*InnerRadius)/144.0;
279 Ixx = 0.5*Mass*RadSumSqr;
280 Iyy = Mass*(3.0*RadSumSqr + Length*Length/144.0)/12.0;
283 Length = Volume/(M_PI*Rad2);
284 Ixx = 0.5*Mass*Rad2/144.0;
285 Iyy = Mass*(3.0*Rad2 + Length*Length)/(144.0*12.0);
292 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
293 // The bitmasked value choices are as follows:
294 // unset: In this case (the default) JSBSim would only print
295 // out the normally expected messages, essentially echoing
296 // the config files as they are read. If the environment
297 // variable is not set, debug_lvl is set to 1 internally
298 // 0: This requests JSBSim not to output any messages
300 // 1: This value explicity requests the normal JSBSim
302 // 2: This value asks for a message to be printed out when
303 // a class is instantiated
304 // 4: When this value is set, a message is displayed when a
305 // FGModel object executes its Run() method
306 // 8: When this value is set, various runtime state variables
307 // are printed out periodically
308 // 16: When set various parameters are sanity checked and
309 // a message is printed out when they go out of bounds
311 void FGTank::Debug(int from)
313 if (debug_lvl <= 0) return;
315 if (debug_lvl & 1) { // Standard console startup message output
316 if (from == 0) { // Constructor
317 cout << " " << type << " tank holds " << Capacity << " lbs. " << type << endl;
318 cout << " currently at " << PctFull << "% of maximum capacity" << endl;
319 cout << " Tank location (X, Y, Z): " << vXYZ(eX) << ", " << vXYZ(eY) << ", " << vXYZ(eZ) << endl;
320 cout << " Effective radius: " << Radius << " inches" << endl;
321 cout << " Initial temperature: " << Temperature << " Fahrenheit" << endl;
324 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
325 if (from == 0) cout << "Instantiated: FGTank" << endl;
326 if (from == 1) cout << "Destroyed: FGTank" << endl;
328 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
330 if (debug_lvl & 8 ) { // Runtime state variables
332 if (debug_lvl & 16) { // Sanity checking
334 if (debug_lvl & 64) {
335 if (from == 0) { // Constructor
336 cout << IdSrc << endl;
337 cout << IdHdr << endl;