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Three dimensional steady flowfield generated by transverse sonic injection into a supersonic flow was simulated by solving the Favre-averaged Navier-Stokes equations using the weighted essentially nonoscillatory (WENO) schemes and Jones-Launder k-e model. Results indicate that in the upstream of the square injection there exist two main recirculation regions and the primary vortex induces the horseshoe vortex region. In the downstream there is a low pressure region which conduces a pair of helical vortex.

[Abstract] A model that is based on the complex physical and chemical processes in the operation of hybrid rocket motor and able to work in different operating conditions, was proposed to predict the flow characteristics and fuel grain pyrolysis surface regression rate in hybrid motors. Navier-Stokes equations coupled with chemical species and turbulence transport equations were applied to simulate unsteady turbulence gas flow in the passage. The equation set was complemented by an additional turbulent model. A low-Reynolds number e − k turbulent model was used to decrease the instability of the heat transfer near the grain surface. The coupling between the solid and gaseous phases was carried out through energy and mass conservation on the interface. Dynamic mesh techniques were used to simulate moving process of the grain surface. The dynamic mesh update methods used in the paper are Spring-Based Smoothing Method and Local Re-meshing Method. The model was validated by comparison between computational and experimental data, and then was used to simulate a lab-scale hybrid rocket motor. Temperature, velocity, and species distributions were obtained, as well as the temperature and regression rate on the grain pyrolysis surface.