화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.121, 1297-1306, 2018
Numerical investigation of transpiration cooling for porous nose cone with liquid coolant
Transpiration cooling is considered a potential candidate as a thermal management tool for the next generation of hypersonic vehicles. This paper presents a numerical investigation on transpiration cooling of a porous nose cone, the behaviors of liquid coolant in transonic flow field under low and high enthalpy conditions are investigated by using the Darcy-Forchheimer model and the local non-equilibrium thermal model. We not only consider the mass and heat transfer in the porous media, but also consider further the heat exchange between the porous media and other regions by an effective two-step multi-region numerical scheme. The experimental photograph of icing under low enthalpy condition and the experimental cooling efficiency under high enthalpy condition are used to compare with the simulation results to verify the accuracy. Velocities and temperatures of coolant in the boundary layer are used to analyze the transpiration process in detail under both conditions. The conversion between internal energy and kinetic energy is used to explain the icing phenomenon under low enthalpy condition, and the thickness change of the boundary layer is used to explain the generation of oblique waves on the cone wall under high enthalpy condition. The simulation results show that the injection of coolant has a significant effect on the morphology of the boundary layer. (C) 2018 Elsevier Ltd. All rights reserved.