Numerical Design Studies on Internal Flow Characteristics of LOX/CH4 Swirl Injector

Numerical design study of the central post of a full-scale liquid oxygen and liquid methane (LOXLCH4) swirl coaxial injector element has been carried out utilizing the unsteady ReynoldsAveraged Navier-Stokes (URANS) approach. The scope of the present study involves water cold flow with atmospheric chamber pressure corresponding to a parallel experimental investigation [6]. To characterize the internal two phase flow of the nozzle, the Eulerian Volume of Fluid (VOF) method was used to capture the sharp liquid-gas interface encountered in liquid swirl injector involving air cores. The goal of the numerical simulation is to predict the liquid film thickness and spray cone angle at the injector exit to be used for subsequent atomization/spray modeling studies. The numerical results are compared with the parallel experimental effort [6]. The 2-D axisymmetric numerical computations performed on the LOX inner swirl injector indicated that the accurate prediction of the liquid film thickness is essential to evaluating the swirling sheet’s free cone spray angle at the exit face of the nozzle.