超临界压力下基于径向热物性分布的碳氢燃料流动换热特性研究  

Heat transfer of hydrocarbon fuel based on thermoproperties radial distribution under supercritical pressure

作　　者：林大森 李海旺[1] 朱剑琴[1,2] 程泽源 魏颍川 胡希卓 LIN Dasen;LI Haiwang;ZHU Jianqin;CHENG Zeyuan;WEI Yingchuan;HU Xizhuo(School of Power and Energy,Beihang University,Beijing 100191,China;Tianmushan Laboratory,Hangzhou 311115,China;College of Aeronautical Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]北京航空航天大学能源与动力工程学院,北京100191 [2]天目山实验室,浙江杭州311115 [3]中国民航大学航空工程学院,天津300300

出　　处：《推进技术》2025年第2期187-199,共13页Journal of Propulsion Technology

基　　金：国家自然科学基金(52122604;52306064;52106121)。

摘　　要：针对超临界加热管内碳氢燃料径向热物性分布及其与管内对流换热之间的耦合机制,建立了二维冷却通道模型,开展了燃料入口温度为300~400 K和热流密度为0.60~0.75 MW/m^(2)工况下碳氢燃料流动换热数值模拟。研究结果表明:加热管内不同换热现象与截面流体热物性径向分布密切相关。流体径向热物性非均匀系数峰值出现在入口换热恶化区;而换热强化现象主要源自于混合物定压比热和导热系数径向分布均匀化,增加燃料吸热的同时又加速了径向的热量传递。当截面流体导热系数径向非均匀系数为0,即导热系数径向变化梯度的方向发生改变时,沿径向的热量传递减小,壁面温度开始升高;同时,当定压比热径向非均匀系数为0时壁面温度增速变缓。燃料入口温度和壁面热流密度分别对低温主流区和高温近壁面区混合物的热物性产生显著影响;增加燃料入口温度和热流密度均能够缩短换热强化作用范围,加大管内轴向流动对换热的影响范围。Aiming at the coupling mechanism between the radial thermoproperties distribution of hydrocar⁃bon fuel and the convective heat transfer in the supercritical heated tube,a two-dimensional cooling channel model was established,and the numerical simulation of hydrocarbon fuel flow heat transfer was carried out under the conditions of fuel inlet temperature of 300~400 K and heat flux of 0.60~0.75 MW/m^(2).The results show that the various heat transfer phenomena occurring within the heated tube are closely associated with the radial distri⁃bution of the cross-section fluid’s thermoproperties.The maximum value of the non-uniformity coefficient of the radial thermal properties of the fluid appears in the heat transfer deterioration zone at the inlet.The phenomenon of heat transfer enhancement is mainly due to the uniform distribution of the specific heat capacity at constant pressure and the thermal conductivity of the mixture,which increases the heat absorption and accelerates the ra⁃dial heat transfer.When the radial non-uniform coefficient of the cross-section fluid thermal conductivity is 0,that is,when the direction of the radial variation gradient of the thermal conductivity changes,the heat transfer along the radial direction decreases and the wall temperature begins to increase.At the same time,when the radi⁃al non-uniformity coefficient of specific heat capacity at constant pressure is 0,the growth rate of wall tempera⁃ture slows down.Fuel inlet temperature and wall heat flux have significant effects on the thermoproperties of the mixture in the mainstream zone with low temperature and near the heated wall with high temperature,respective⁃ly.Increasing the fuel inlet temperature and heat flux can reduce the extent of heat transfer enhancement and ex⁃pand the influence of axial flow on heat transfer.

关 键 词：超临界 碳氢燃料 热物性 非均匀系数 流动换热 

分 类 号：V312.1[航空宇航科学与技术—航空宇航推进理论与工程]