Large eddy simulation of cryogenic coaxial LN2/GH2 injection under supercritical pressures

Abstract

The coaxial injection of cryogenic nitrogen and warm hydrogen into a supercritical nitrogen atmosphere is studied numerically by means of well resolved large-eddy simulation (LES). Numerical data for two operating conditions are compared both quantitatively and qualitatively with a series of experiments [Oschwald et al., 35th AIAA/ASME/SAE/ASEE Joint Propulsion Conference, 1999], A detailed thermodynamic analysis of phenomena associated with the binary mixing of nitrogen and hydrogen together with a systematic study of the thermodynamic state of cryogenic nitrogen prior to injection allows an assessment of uncertainties related to both numerical and experimental data. Trans- and supercritical mixing constitutes considerable challenges for numerical simulations with regard to physical modeling and numerical stability. We compare a fully conservative (FC) formulation to a quasi conservative (QC) formulation of the governing equation, which was recently proposed by Terashima and Koshi [J. Comput. Phys., 2012].