git.gag.com Git - sw/motorsim/blob - src/com/billkuker/rocketry/motorsim/fuel/PiecewiseLinearFuel.java

   1 package com.billkuker.rocketry.motorsim.fuel;\r
   2 \r
   3 import java.net.URI;\r
   4 import java.util.NoSuchElementException;\r
   5 import java.util.SortedMap;\r
   6 import java.util.TreeMap;\r
   7 \r
   8 import javax.measure.quantity.Dimensionless;\r
   9 import javax.measure.quantity.Pressure;\r
  10 import javax.measure.quantity.Velocity;\r
  11 import javax.measure.quantity.VolumetricDensity;\r
  12 import javax.measure.unit.SI;\r
  13 \r
  14 import org.apache.log4j.Logger;\r
  15 import org.jscience.physics.amount.Amount;\r
  16 \r
  17 import com.billkuker.rocketry.motorsim.Fuel;\r
  18 import com.billkuker.rocketry.motorsim.visual.Chart;\r
  19 \r
  20 public class PiecewiseLinearFuel implements Fuel{\r
  21         private static final Logger log = Logger.getLogger(PiecewiseLinearFuel.class);\r
  22         \r
  23         private String name;\r
  24         private URI uri;\r
  25         private Amount<VolumetricDensity> density;\r
  26         private float densityRatio;\r
  27         private float combustionEfficiency;\r
  28         \r
  29         private class Entry implements Comparable<Entry>{\r
  30                 Amount<Pressure> pressure;\r
  31                 Amount<Velocity> burnRate;\r
  32                 @Override\r
  33                 public int compareTo(Entry o) {\r
  34                         if ( o.pressure.approximates(pressure) )\r
  35                                 return 0;\r
  36                         return o.pressure.isGreaterThan(pressure)?-1:1;\r
  37                 }\r
  38         }\r
  39         \r
  40         private SortedMap<Amount<Pressure>, Entry> entries = new TreeMap<Amount<Pressure>, Entry>();\r
  41         \r
  42         protected void add(final Amount<Pressure> p, final Amount<Velocity> r){\r
  43                 entries.put(p, new Entry(){{pressure = p; burnRate = r;}});\r
  44         }\r
  45         \r
  46         public PiecewiseLinearFuel(){\r
  47                 add(Amount.valueOf(-1,SI.MEGA(SI.PASCAL)), Amount.valueOf(0, SI.METERS_PER_SECOND));\r
  48                 add(Amount.valueOf(0,SI.MEGA(SI.PASCAL)), Amount.valueOf(0, SI.METERS_PER_SECOND));\r
  49         }\r
  50 \r
  51         @Override\r
  52         public String getName() {\r
  53                 return name;\r
  54         }\r
  55 \r
  56         @Override\r
  57         public URI getURI() {\r
  58                 return uri;\r
  59         }\r
  60 \r
  61         @Override\r
  62         public Amount<VolumetricDensity> getIdealDensity() {\r
  63                 return density;\r
  64         }\r
  65 \r
  66         @Override\r
  67         public Amount<Velocity> burnRate(Amount<Pressure> pressure) {\r
  68                 Entry low = null;\r
  69                 low = entries.get(entries.headMap(pressure).lastKey());\r
  70                 Entry high = null;\r
  71                 try {\r
  72                         high = entries.get(entries.tailMap(pressure).firstKey());\r
  73                 } catch ( NoSuchElementException e ){\r
  74                         log.warn("Pressure " + pressure + " is outside of expiermental range for " + this.getName());\r
  75                         high = low;\r
  76                         low = entries.get(entries.headMap(low.pressure).lastKey());\r
  77                 }\r
  78                 \r
  79                 Amount<Pressure> lowToHigh = high.pressure.minus(low.pressure);\r
  80                 Amount<Pressure> lowToTarget = pressure.minus(low.pressure);\r
  81                 Amount<Dimensionless> frac = lowToTarget.divide(lowToHigh).to(Dimensionless.UNIT);\r
  82                 \r
  83                 Amount<Velocity> vdiff = high.burnRate.minus(low.burnRate);\r
  84                 Amount<Velocity> ret = low.burnRate.plus(vdiff.times(frac));\r
  85                 \r
  86                 return ret;\r
  87                 \r
  88         }\r
  89 \r
  90         @Override\r
  91         public CombustionProduct getCombustionProduct(){\r
  92                 return null;\r
  93         }\r
  94 \r
  95         @Override\r
  96         public double getDensityRatio() {\r
  97                 return densityRatio;\r
  98         }\r
  99 \r
 100         @Override\r
 101         public double getCombustionEfficiency() {\r
 102                 return combustionEfficiency;\r
 103         }\r
 104 \r
 105         public static void main( String args[]) throws Exception{\r
 106                 PiecewiseLinearFuel f = new PiecewiseLinearFuel();\r
 107                 f.add(Amount.valueOf(0,SI.MEGA(SI.PASCAL)), Amount.valueOf(0, SI.METERS_PER_SECOND));\r
 108                 f.add(Amount.valueOf(2,SI.MEGA(SI.PASCAL)), Amount.valueOf(2, SI.METERS_PER_SECOND));\r
 109                 f.add(Amount.valueOf(4,SI.MEGA(SI.PASCAL)), Amount.valueOf(1, SI.METERS_PER_SECOND));\r
 110                 f.add(Amount.valueOf(10,SI.MEGA(SI.PASCAL)), Amount.valueOf(3, SI.METERS_PER_SECOND));\r
 111                 f.add(Amount.valueOf(20,SI.MEGA(SI.PASCAL)), Amount.valueOf(4, SI.METERS_PER_SECOND));\r
 112                 Chart<Pressure, Velocity> burnRate = new Chart<Pressure, Velocity>(\r
 113                                 SI.MEGA(SI.PASCAL),\r
 114                                 SI.METERS_PER_SECOND,\r
 115                                 f,\r
 116                                 "burnRate");\r
 117                 burnRate.setDomain(\r
 118                                 burnRate.new IntervalDomain(\r
 119                                                 Amount.valueOf(0, SI.MEGA(SI.PASCAL)),\r
 120                                                 Amount.valueOf(11, SI.MEGA(SI.PASCAL)),\r
 121                                                 200\r
 122                                                 ));\r
 123                 \r
 124                 burnRate.show();\r
 125         }\r
 126 }\r