Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor  

作　　者：Jianfei WEI Silong ZHANG Jingying ZUO Xin LI Jiang QIN Wen BAO 

机构地区：[1]School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Chinese Journal of Aeronautics》2024年第7期109-133,共25页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52176037).

摘　　要：Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic conditions.Large eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive circumstances.The results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel films.The turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction applications.Besides,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat addition.However,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the wall.On the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the wall.Overall,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关 键 词：Supersonic film cooling HYDROGEN HYDROCARBON Boundary layer combustion Large eddy simulation 

分 类 号：V235.21[航空宇航科学与技术—航空宇航推进理论与工程]