摘要
高马赫数下超燃冲压发动机壁面冷却通道受高热流密度影响易损毁从而导致发动机失效,研究壁面冷却通道冷却性能有利于改善受热不均匀的现象。因此,本文提出液态金属-碳氢燃料双层冷却通道,搭建了液态金属流动换热试验系统,验证了仿真试验系统具有较好的精确度。仿真结果表明,裂解反应提高了燃料的总热沉,同时也加剧了通道内的热分层现象,这是双通道燃料裂解反应带来的双重效应,且在高热流密度工况下体现得更突出;与正癸烷单通道相比,双通道正癸烷侧可将温度不均匀系数R_(T)最大值从55%左右降到18%左右,热沉不均匀系数R_(H)最大值从1000%左右下降至不到100%;与液态金属单通道相比,双通道液态金属侧可将R_(H)最大值从230%降低至80%左右,说明双通道结构有效改善了液态金属在通道内吸收热量的均匀性。本文研究结果为液态金属冷却系统获得合适的燃烧室壁面冷却通道参数提供理论指导。
At high Mach numbers,the cooling channels on the scramjet wall are susceptible to damage due to the influence of high heat flux density,leading to engine failure.Researching the cooling performance of wall cooling channels is beneficial for improving the phenomenon of uneven heating.Therefore,this paper proposes a double-layer cooling channel using liquid metal and hydrocarbon fuel.A flow and heat transfer test system of liquid metal was established to verify that the simulation has good accuracy.Simulation results show that the cracking reaction increases the total heat sink of the fuel while also aggravating the thermal stratification phenomenon within the channel.This is a dual effect brought by the cracking reaction of the dual-channel fuel,which is more prominent under high heat flux conditions.Compared with the single-channel of n-decane,the maximum of R_(T) on the side of n-decane of dual-channel can be reduced from about 55%to about 18%,and the maximum of R_(H) can be reduced from about 1000%to less than 100%.Compared with the single-channel of liquid metal,the maximum of R_(H) on the side of liquid metal of dual-channel can be reduced from 230%to about 80%,indicating that the dual-channel structure effectively improves the uniformity of heat absorption by liquid metal within the channel.This study provides theoretical guidance for obtaining appropriate combustor wall cooling channel parameters for liquid metal cooling systems.
作者
徐静
党朝磊
王毅琳
王思博
程昆林
秦江
刘小勇
Xu Jing;Dang Chaolei;Wang Yilin;Wang Sibo;Cheng Kunlin;Qin Jiang;Liu Xiaoyong(Harbin Institute of Technology,Harbin 150001,China)
出处
《航空科学技术》
2024年第12期16-27,共12页
Aeronautical Science & Technology
基金
航空科学基金(20230028077001)。
关键词
液态金属
碳氢燃料
壁面冷却通道
裂解反应
热分层
liquid metal
hydrocarbon fuel
wall cooling channel
cracking reaction
thermal stratification
