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

   1 package com.billkuker.rocketry.motorsim;\r
   2 \r
   3 import javax.measure.quantity.Dimensionless;\r
   4 import javax.measure.quantity.Duration;\r
   5 import javax.measure.quantity.Force;\r
   6 import javax.measure.quantity.Mass;\r
   7 import javax.measure.quantity.Pressure;\r
   8 import javax.measure.quantity.Volume;\r
   9 import javax.measure.quantity.VolumetricDensity;\r
  10 import javax.measure.unit.SI;\r
  11 \r
  12 import org.jscience.physics.amount.Amount;\r
  13 \r
  14 import com.billkuker.rocketry.motorsim.Burn.Interval;\r
  15 \r
  16 public class BurnSummary {\r
  17 \r
  18         Amount<RocketScience.Impulse> ns = Amount.valueOf(0,\r
  19                         RocketScience.NEWTON_SECOND);\r
  20 \r
  21         Amount<Duration> thrustTime = Amount.valueOf(0, SI.SECOND);\r
  22         Amount<Force> maxThrust = Amount.valueOf(0, SI.NEWTON);\r
  23         Amount<Pressure> maxPressure = Amount.valueOf(0, SI.MEGA(SI.PASCAL));\r
  24         Amount<Duration> isp;\r
  25         Amount<Mass> propellantMass;\r
  26         Double saftyFactor;\r
  27         \r
  28         public BurnSummary(Burn b) {\r
  29                 for (Interval i : b.getData().values()) {\r
  30                         ns = ns.plus(i.dt.times(i.thrust));\r
  31                         if (i.thrust.isGreaterThan(Amount.valueOf(0.01, SI.NEWTON))) {\r
  32                                 thrustTime = thrustTime.plus(i.dt);\r
  33                         }\r
  34                         if (i.thrust.isGreaterThan(maxThrust))\r
  35                                 maxThrust = i.thrust;\r
  36                         if (i.chamberPressure.isGreaterThan(maxPressure))\r
  37                                 maxPressure = i.chamberPressure;\r
  38                 }\r
  39                 \r
  40                 isp = ns\r
  41                 .divide(b\r
  42                                 .getMotor()\r
  43                                 .getGrain()\r
  44                                 .volume(Amount.valueOf(0, SI.MILLIMETER))\r
  45                                 .times(b.getMotor()\r
  46                                                 .getFuel()\r
  47                                                 .getIdealDensity()\r
  48                                                 .times(b.getMotor().getFuel()\r
  49                                                                 .getDensityRatio())))\r
  50                 .to(SI.METERS_PER_SECOND)\r
  51                 .divide(Amount.valueOf(9.81,\r
  52                                 SI.METERS_PER_SQUARE_SECOND)).to(SI.SECOND);\r
  53 \r
  54                 if ( b.getMotor().getChamber().getBurstPressure() != null )\r
  55                         saftyFactor = b.getMotor().getChamber().getBurstPressure().divide(maxPressure).to(Dimensionless.UNIT).doubleValue(Dimensionless.UNIT);\r
  56 \r
  57                 Amount<Volume> vol = b.getMotor().getGrain().volume(Amount.valueOf(0, SI.MILLIMETER));\r
  58                 Amount<VolumetricDensity> ideal = b.getMotor().getFuel().getIdealDensity();\r
  59                 Amount<VolumetricDensity> actual = ideal.times(b.getMotor().getFuel().getDensityRatio());\r
  60                 propellantMass = vol.times(actual).to(SI.GRAM);\r
  61         }\r
  62 \r
  63         public String getRating() {\r
  64                 float cnf = (float) (Math.log(ns\r
  65                                 .doubleValue(RocketScience.NEWTON_SECOND) / 1.25) / Math\r
  66                                 .log(2));\r
  67                 int cn = (int) cnf;\r
  68                 float fraction = cnf - cn;\r
  69                 int percent = (int) (100 * fraction);\r
  70                 char cl = (char) ((int) 'A' + cn);\r
  71                 \r
  72                 return percent + "% "\r
  73                 + new String(new char[] { cl }) + "-"\r
  74                 + Math.round(averageThrust().doubleValue(SI.NEWTON));\r
  75         }\r
  76 \r
  77         public Double getSaftyFactor(){\r
  78                 return saftyFactor;\r
  79         }\r
  80         \r
  81         public Amount<RocketScience.Impulse> totalImpulse() {\r
  82                 return ns;\r
  83         }\r
  84 \r
  85         public Amount<Duration> thrustTime() {\r
  86                 return thrustTime;\r
  87         }\r
  88 \r
  89         public Amount<Force> maxThrust() {\r
  90                 return maxThrust;\r
  91         }\r
  92         \r
  93         public Amount<Duration> specificImpulse(){\r
  94                 return isp;\r
  95         }\r
  96 \r
  97         public Amount<Force> averageThrust() {\r
  98                 Amount<Force> averageThrust = Amount.valueOf(0, SI.NEWTON);\r
  99                 if (thrustTime().isGreaterThan(Amount.valueOf(0, SI.SECOND)))\r
 100                         averageThrust = totalImpulse().divide(thrustTime).to(SI.NEWTON);\r
 101                 return averageThrust;\r
 102         }\r
 103 \r
 104         public Amount<Pressure> maxPressure(){\r
 105                 return maxPressure;\r
 106         }\r
 107         \r
 108         public Amount<Mass> getPropellantMass() {\r
 109                 return propellantMass;\r
 110         }\r
 111 \r
 112 }\r