Based on the PR(Peng-Robinson) equation of state

two-dimensional axisymmetric governing equation of two-phase flow was introduced to establish a numerical model of supercritical injection by employing the mixing rule described in relevant references. And preconditioning method was used for solving

while n-decane was used as an alternative of liquid hydrocarbon fuel to investigate the supercritical injection characteristics in a quiescent supercritical nitrogen chamber. The jet length and jet spreading angle affected by ambient and injection parameters were separately analyzed. This demonstrates that jet length and jet spreading angle decrease with the increasing ambient pressure

but increase with the increasing ambient and injection temperature. The sensitivity of supercritical jet length affected by ambient and injection parameters is higher than jet spreading angle. It is deemed that the injection density ratio and injection momentum are two main influential factors to the supercritical injection

and the injection momentum is considered to be the dominant factor.