Numerical investigation of supercritical LOX/Methane cryogenic combustion in a rocket combustion chamber

Kurzfassung

This paper presents simulation activities performed in the frame of a partnership program between the German Aerospace Center (DLR) and the launcher directorate of the French National Center for Space Studies (CNES). The specific test case presented in this paper is a supercritical LOx-methane combustion test on the penta-injector combustion chamber BhpHrM (high pressure and high mixture ratio) of ONERA's test bench Mascotte. The current paper presents numerical works on the hot gas-side analysis of a LOx-methane combustion chamber. Two different simulation approaches are compared in this paper. Both simulations are Reynolds-averaged Navier−Stokes (RANS) simulations. The DLR simulation is computed with the DLR computational fluid dynamics (CFD) code TAU. It uses a flamelet model to solve the combustion coupled to the Soave−Redlich−Kwong (SRK) equation of state. It also uses a low Reynolds approach to model the heat transfer. The CNES simulations have been performed with CPS_C by CT Ingénierie. CPS_C uses a finite rate chemistry model with a 9-species and 21-reaction kinetic scheme coupled to the SRK equation of state. The paper investigates the temperature and species distribution within the flow field of the combustion chamber. It shows the difference in oxygen cores length, flame shapes, and recirculation zones within the major axis of the flow field and several axial cuts. The upsides and downsides of the specific modeling approaches are presented and compared. Finally, the experimental measurements of the wall temperature are compared to the wall temperature obtained from the simulation. The complex three-dimensional shape of the wall heat flux and temperatures are not captured in their entirety, especially in the front half of the combustion chamber. In contrast, in the latter half of the combustion chamber the values for temperature and wall heat flux correspond quite well between simulation and experiment.