Numerical flowfield analysis of the next generation Vulcan nozzle

Abstract

For numerical simulations of reacting, viscous nozzle flows in advanced rocket nozzles, a numerical method has been developed. The code is based on the well-established DLR Euler/thin layer Navier Stokes code NSHYP that was originally written for hypersonic re-entry flow simulations. The code solves the three-dimensional, time-dependent Euler and thin-layer Navier- Stokes equations in conservation-law form. Hydrogen and oxygen are considered as fuel and oxidizer, respectively. The passive scalar approach accounts for the multicomponent diffusion effects. Turbulent transport is described with an algebraic eddy-viscosity, and a &-e two-equations model. Calculations of conventional bell nozzles were performed. Results of Vulcan Mark 1 nozzle flow simulations are shown and compared in detail with another wellestablished numerical approach, based on the method of characteristi cs. A modified Vulcan engine is proposed, where the gas generator exhaust gases are injected into the main nozzle. Results of an engine analysis are presented. Based on this engine analysis, numerical flowfield calculations of the modified nozzle were performed and are presented.