CR=2.5, eps=62.5, pcentBell=72.3,
RupThroat=1.5, RdwnThroat=1.0, RchmConv=1.0, cham_conv_deg=30,
LchmOvrDt=3.10, LchmMin=2.0, LchamberInp=None)
effObj = Efficiencies()
effObj.set_const('ERE', 0.98) # don't know injector details so set effERE=0.98
# It's an ablative chamber, so some FFC (fuel film cooling) is required... guess about 15%
core = CoreStream( geomObj=geomObj, effObj=effObj, pcentFFC=15.0,
oxName='N2O4', fuelName='A50', MRcore=1.6, Pc=100 )
R = RocketThruster(name='Apollo SPS',coreObj=core)
# scale geometry to give 20,500 lbf of thrust for current conditions
R.scale_Rt_to_Thrust( 20500 , Pamb=0.0 )
# figure out best mixture ratio to run the engine.
R.set_mr_to_max_ispdel()
# re-scale geometry to give 20,500 lbf of thrust after MR change
R.scale_Rt_to_Thrust( 20500 , Pamb=0.0 )
fsave = 'Apollo_SPS.html'
fOut = open(fsave , 'w')
fOut.write( R.get_html_file_str() )
fOut.close()
webbrowser.open( os.path.abspath(fsave) )
from rocketisp.geometry import Geometry
from rocketisp.efficiencies import Efficiencies
from rocketisp.stream_tubes import CoreStream
from rocketisp.rocket_isp import RocketThruster
# create CoreStream with area ratio=375:1, Pc=137, FFC=30% and effERE=0.99
C = CoreStream( geomObj=Geometry(eps=375),
effObj=Efficiencies(ERE=0.99), pcentFFC=30,
oxName='N2O4', fuelName='N2H4', MRcore=1.26 ,
Pc=137, Pamb=0)
# instantiate RocketThruster
R = RocketThruster(name='100 lbf Aerojet HiPAT R-4D', coreObj=C)
R.scale_Rt_to_Thrust( 100 , Pamb=0.0 )
MRcore_opt = R.set_mr_to_max_ispdel()
print('MRcore_opt = %g'%MRcore_opt)
R.summ_print()