an arrangement for determining {HEAD ~ the combustion duration} from {TAIL ~ an energy conversion} which is calculated using a polytropic equation of state 
an arrangement for determining { HEAD ~ the combustion duration } from { TAIL ~ an energy conversion } which is calculated using a polytropic equation of state
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH