# Coverage for rocketcea\biprop_utils\mr_peak_at_eps_pc.py : 14%

## 147 statements 20 run 127 missing 0 excluded

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 | import sys import numpy as np from rocketcea.biprop_utils.mr_t_limits import MR_Temperature_Limits from rocketcea.Goal import Goal from rocketcea.biprop_utils.run_cea_w_error_corr import run_cea_ode, run_cea_odf from rocketcea.biprop_utils.goldSearch import search_max as gold_search_max from rocketcea.biprop_utils.InterpProp_scipy import InterpProp """ ----------------------- biprop_utils Copyright (C) 2015 Charlie Taylor This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. ----------------------- __author__ = 'Charlie Taylor' __copyright__ = 'Copyright (c) 2015 Charlie Taylor' __license__ = 'GPL-3' __email__ = "cet@appliedpython.com" """ def frac_ox( MR ): """return the fraction of ox (fox) for given MR""" return MR / (MR + 1.0) MR_MAX = 1000.0 def mr_of_fracox( fox ): """return the MR for given ox fraction (fox)""" if fox < 1.0: mr = fox / (1.0 - fox) return min( mr, MR_MAX ) else: return MR_MAX class MR_Peak_At_EpsPc( object ): def __str__(self): return '''<mrPeak=%g, ispPeak=%g, mrLeftOfPeak=%g, mrRightOfPeak=%g, pc=%g, eps=%g>'''%\ (self.mrPeak, self.ispPeak, self.mrLeftOfPeak, self.mrRightOfPeak, self.pc, self.eps) def __init__(self, mrLimitsObj, pc=100., eps=10., ispType='CEAODE', # ispType can be CEAODE, CEAFROZEN NterpSize=100): # size of interpolation array self.mrLimitsObj = mrLimitsObj self.pc = pc self.eps = eps self.ispType = ispType self.mrL = [] # build lists of non-zero isp both above and below stoich_MR self.isL = [] stoich_MR = self.mrLimitsObj.Stoich_MR #print( 'stoich_MR =',stoich_MR) stoich_fox = frac_ox( stoich_MR ) #print( 'stoich_fox =',stoich_fox) self.stoich_fox = stoich_fox stoich_Isp = self.isp_at_mr( mr=stoich_MR ) # build mr and isp lists from the stoich point to the left and right. # Only bother doing this because CEA frozen calc will often fail with condensed species. # build list from stoich towards MR=0 mr_leftL = [stoich_MR] is_leftL = [ stoich_Isp ] df = 1.0 / float(NterpSize) fox = stoich_fox - df while fox > 0.0: mr = mr_of_fracox( fox ) isp = self.isp_at_mr( mr=mr ) if isp > 1.0: mr_leftL.append( mr ) is_leftL.append( isp ) fox = fox - df if isp < stoich_Isp*0.9: break else: break #print 'mr_leftL =',mr_leftL #print 'is_leftL =',is_leftL # build list from stoich towards ox fraction = 1.0 mr_rightL = [] is_rightL = [] fox = stoich_fox + df while fox < 1.0: mr = mr_of_fracox( fox ) isp = self.isp_at_mr( mr=mr ) if isp > 1.0: mr_rightL.append( mr ) is_rightL.append( isp ) fox = fox + df if isp < stoich_Isp*0.9: break else: break #print 'mr_rightL =',mr_rightL #print 'is_rightL =',is_rightL # combine both lists mr_leftL.reverse() is_leftL.reverse() self.mrL = mr_leftL + mr_rightL self.isL = is_leftL + is_rightL if len( self.mrL ) < 3: print('ERROR... len(mrL) < 3') #print 'Optimizing pc=%g, eps=%g'%(pc, eps) self.mr_isp_terp = InterpProp(self.mrL, self.isL) self.mrPeak, iterp_peak = gold_search_max(self.mr_isp_terp, self.mrL[0], self.mrL[-1], tol=1.0e-5) self.ispPeak = self.isp_at_mr( mr=self.mrPeak ) self.isp_min = min( self.isL ) self.isp_max = max( self.isL ) if self.ispPeak < 0.01 or self.mrPeak < 0.0: imin = 0 for i in range( len(self.mrL) ): if self.isL[i] < self.isL[imin]: imin = i imax = min(len(self.mrL)-1, imin+2) imin = max(0, imin-2) self.mrPeak, iterp_peak = gold_search_max(self.mr_isp_terp, self.mrL[imin], self.mrL[imax], tol=1.0e-5) self.ispPeak = self.isp_at_mr( mr=self.mrPeak ) if self.ispPeak < 0.01 or self.mrPeak < 0.0: print(( '_______________BAD OPTIMUM at pc=%g and eps=%g mrPeak=%g, ispPeak=%g'%(pc, eps, self.ispPeak, self.mrPeak))) # place holders for left and right of peak Isp self._mrLeftOfPeak = None self._mrRightOfPeak = None @property def mrLeftOfPeak(self): # 1st point if self._mrLeftOfPeak is None: self.calc_mrLow_minus_NPcentIsp() return self._mrLeftOfPeak @property def mrRightOfPeak(self): # 1st point if self._mrRightOfPeak is None: self.calc_mrHigh_minus_NPcentIsp() return self._mrRightOfPeak def isp_at_mr(self, mr): '''Return Isp from either CEA or TDK program. Can be ODE or Frozen. Return value is determined by ispType flag (CEAODE, CEAFROZEN) ''' if self.ispType=='CEAODE': return run_cea_ode(self.mrLimitsObj.ispODEObj, Pc=self.pc, MR=mr, eps=self.eps ) elif self.ispType=='CEAFROZEN': ispFroz = run_cea_odf(self.mrLimitsObj.ispODEObj, Pc=self.pc, MR=mr, eps=self.eps ) return ispFroz else: print('ERROR... illegal value for ispType',self.ispType,'(should be CEAODE, CEAFROZEN)') sys.exit() def calc_mrLow_minus_NPcentIsp(self, NPcent=3.0): # N % lower than Peak Isp ispTarget = self.ispPeak * (100.0-NPcent)/100.0 G = Goal(goalVal=ispTarget, minX=self.mrL[0], maxX=self.mrPeak, funcOfX=self.mr_isp_terp, tolerance=1.0E-4, maxLoops=40, failValue=None) self._mrLeftOfPeak, self.ierrorLowIsp = G() if self.ierrorLowIsp: print('WARNING... mrLeftOfPeak NOT found. Setting equal to mrPeak') self._mrLeftOfPeak = self.mrPeak if self._mrLeftOfPeak < 0.01: print('WARNING... mrLeftOfPeak is Too Low. Setting equal to mrPeak') self._mrLeftOfPeak = 0.01 return self._mrLeftOfPeak def calc_mrHigh_minus_NPcentIsp(self, NPcent=3.0): # N % lower than Peak Isp ispTarget = self.ispPeak * (100.0-NPcent)/100.0 G = Goal(goalVal=ispTarget, minX=self.mrPeak, maxX=self.mrL[-1], funcOfX=self.mr_isp_terp, tolerance=1.0E-4, maxLoops=40, failValue=None) self._mrRightOfPeak, self.ierrorHighIsp = G() if self.ierrorHighIsp: print('WARNING... mrRightOfPeak NOT found. Setting equal to mrPeak') self._mrRightOfPeak = self.mrPeak print(self) #if self._mrRightOfPeak>5.0: # print self return self._mrRightOfPeak def get_peak_mr_vs_isp_lists(self, Npts=20): mrL = list( np.linspace(self.mrLeftOfPeak, self.mrRightOfPeak, Npts) ) ispL = [self.isp_at_mr( mr=mr) for mr in mrL] return mrL, ispL if __name__=="__main__": from pylab import * mc = MR_Temperature_Limits(oxName='F2', fuelName='H2', oxPcentL=None, fuelPcentL=None, TC_LIMIT=1400.0, PcNominal=200.0, epsNominal=3.0, MR_MIN=0.0, MR_MAX=1000.0) print('Stoich MR =',mc.Stoich_MR,'for %s/%s'%(mc.cea_oxName, mc.cea_fuelName)) print() print('Min MR = %g'%mc.min_MR, ' Tc at Min MR =',mc.Tc_at_min_MR) print('Max MR = %g'%mc.max_MR, ' Tc at Max MR =',mc.Tc_at_max_MR) mrcurve = MR_Peak_At_EpsPc( mc, pc=1000., eps=10., ispType='CEAFROZEN')#'CEAFROZEN' ) print('Peak IspODE=%g sec at MR ='%mrcurve.ispPeak,mrcurve.mrPeak) print() print('MR at 97% Isp (on low side) =', mrcurve.mrLeftOfPeak) print('MR at 97% Isp (on high side) =', mrcurve.mrRightOfPeak) mrlo = 1.01 * mrcurve.mrL[0] mrhi = 0.99 * mrcurve.mrL[-1] mrL = np.linspace(mrlo, mrhi, 100) foxL = [frac_ox(mr) for mr in mrL] ispL = [mrcurve.isp_at_mr( mr=mr) for mr in mrL] title( '%s/%s'%(mc.cea_oxName, mc.cea_fuelName) + ' ' + mrcurve.ispType ) #plot(mrL, ispL) plot(foxL, ispL) foxL = [frac_ox(mr) for mr in mrcurve.mrL] plot(foxL, [i for i in mrcurve.isL], 's') #plot(mrL, ispL, 'o') mrL = [mrcurve.mrLeftOfPeak, mrcurve.mrPeak, mrcurve.mrRightOfPeak] foxL = [frac_ox(mr) for mr in mrL] ispL = [mrcurve.isp_at_mr( mr=mr) for mr in mrL] plot(foxL, ispL, 'o') axvline( mrcurve.stoich_fox ) #mrL = [i*.04 for i in range(150)] #ispL = [mrcurve.mr_isp_terp(mr) for mr in mrL] #plot(mrL, ispL, '.') #print('mrcurve.mrL =',mrcurve.mrL) #print('mrcurve.isL =',mrcurve.isL) show()