Correlation of specific impulse and ignition delay in liquid rocket propellants

Abstract

Theoretically there seems to be a linear dependence between specific impulse and the ignition delay in liquid bipropellant systems. It has been observed that the plot of specific impulse versus mixture ratio of various systems based on red fuming nitric acid oxidizer show a maximum. The ignition delay versus mixture ratio plot of the same systems on the other hand show a minimum at a mixture ratio which corresponds to the maximum specific impulse. Thus, the mixture corresponding to maximum performance of a liquid bipropellant system could be qualitatively predicted from the ignition delay measurements.