# Coverage for rocketcea\biprop_utils\run_cea_w_error_corr.py : 94%

## 66 statements 62 run 4 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 | from __future__ import print_function '''If CEA gives back Isp==0, then try to estimate it.''' """ ----------------------- 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 make_cea_ode_est(cea_ispObj, Pc=100.0, MR=1.0, eps=40.0): # Got here if simple call did not work # Try averaging a high and low Pc pc_hi = Pc * 1.05 pc_lo = Pc * 0.95 ispODE_hi = cea_ispObj.get_Isp( Pc=pc_hi, MR=MR, eps=eps) ispODE_lo = cea_ispObj.get_Isp( Pc=pc_lo, MR=MR, eps=eps) # If both look good, take the average if ispODE_hi>0.1 and ispODE_lo>0.1: ispODE = (ispODE_hi+ispODE_lo)/2.0 else: # hope there's a good one (Is hope a plan?) ispODE = max(ispODE_hi, ispODE_lo) print( 'WARNING... make_cea_ode_est is returning max of hi and low =',ispODE ) print( 'Estimated CEA_Isp at Pc=%g, MR=%g, eps=%g'%(Pc, MR, eps),'ispODE%g'%ispODE ) return ispODE def make_cea_odf_est(cea_ispObj, Pc=100.0, MR=1.0, eps=40.0): # Got here if simple call did not work # Try averaging a high and low Pc pc_hi = Pc * 1.05 pc_lo = Pc * 0.95 ispFroz_hi,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=pc_hi, MR=MR, eps=eps, frozenAtThroat=0) ispFroz_lo,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=pc_lo, MR=MR, eps=eps, frozenAtThroat=0) # If both look good, take the average if ispFroz_hi>0.1 and ispFroz_lo>0.1: ispFroz = (ispFroz_hi+ispFroz_lo)/2.0 else: # hope there's a good one (Is hope a plan?) ispFroz = max(ispFroz_hi, ispFroz_lo) if ispFroz <= 0.1: print( "Searching...", end='') for i_hope in range(18): if ispFroz <= 0.1: print( ".", end='') pc_hi *= 1.1 pc_lo *= 0.9 ispFroz_hi,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=pc_hi, MR=MR, eps=eps, frozenAtThroat=0) ispFroz_lo,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=pc_lo, MR=MR, eps=eps, frozenAtThroat=0) ispFroz = max(ispFroz_hi, ispFroz_lo) if ispFroz <= 0.1: print( "_NOT_FOUND_") print( 'Estimated CEA_Isp Frozen at Pc=%g, MR=%g, eps=%g'%(Pc, MR, eps),'ispFroz=%g'%ispFroz) else: print('') #print( 'Estimated CEA_Isp Frozen at Pc=%g, MR=%g, eps=%g'%(Pc, MR, eps),'ispFroz=%g'%ispFroz) return ispFroz def run_cea_ode(cea_ispObj, Pc=100.0, MR=1.0, eps=40.0): ispODE = cea_ispObj.get_Isp( Pc=Pc, MR=MR, eps=eps) if ispODE > 0.1: # i.e. it's probably OK return ispODE else: return make_cea_ode_est(cea_ispObj, Pc=Pc, MR=MR, eps=eps) def run_cea_odf(cea_ispObj, Pc=100.0, MR=1.0, eps=40.0): ispFroz,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=Pc, MR=MR, eps=eps, frozenAtThroat=0) if ispFroz > 0.1: # i.e. it's probably OK return ispFroz else: return make_cea_odf_est(cea_ispObj, Pc=Pc, MR=MR, eps=eps) def run_all_cea(cea_ispObj, Pc=100.0, MR=1.0, eps=40.0): ispFroz,cstrODE,tcODE = cea_ispObj.getFrozen_IvacCstrTc( Pc=Pc, MR=MR, eps=eps, frozenAtThroat=0) if ispFroz < 0.1: # try a guess ispFroz = make_cea_odf_est(cea_ispObj, Pc=Pc, MR=MR, eps=eps) ispODE = run_cea_ode(cea_ispObj, Pc=Pc, MR=MR, eps=eps) return ispODE, ispFroz, cstrODE, tcODE if __name__=="__main__": from rocketcea.cea_obj import CEA_Obj cea_ispObj = CEA_Obj(oxName='LOX', fuelName='LH2') for pc,mr,eps in [(100.,1.0,40),(100.,2.0,40),(400.,1.2453509339,32.),(400.,2.5,32.)]: isp_ode = run_cea_ode(cea_ispObj, Pc=pc, MR=mr, eps=eps) isp_odf = run_cea_odf(cea_ispObj, Pc=pc, MR=mr, eps=eps) isp_est = make_cea_ode_est(cea_ispObj, Pc=pc, MR=mr, eps=eps) isp_froz_est = make_cea_odf_est(cea_ispObj, Pc=pc, MR=mr, eps=eps) print( ' isp_ode =',isp_ode) print( ' isp_odf =',isp_odf) print( ' isp_est =',isp_est) print( 'isp_froz_est =',isp_froz_est) print('') ispODE, ispFroz, cstrODE, tcODE = run_all_cea(cea_ispObj, Pc=100.0, MR=6.0, eps=40.0) print('Run All:', ispODE, ispFroz, cstrODE, tcODE)