冲压发动机喷管超临界压力燃油冷却特性  

Supercritical pressure fuel cooling characteristics of ramjet nozzle

作　　者：史一诺 单勇[1] 谭晓茗[1] 张靖周[1] 孙文静 SHI Yinuo;SHAN Yong;TAN Xiaoming;ZHANG Jingzhou;SUN Wenjing(College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Beijing Power Machinery Institute,China Aerospace Science and Industry Corporation Limited,Beijing 100074,China)

机构地区：[1]南京航空航天大学能源与动力学院,南京210016 [2]中国航天科工集团有限公司北京动力机械研究所,北京100074

出　　处：《航空动力学报》2024年第10期217-228,共12页Journal of Aerospace Power

摘　　要：在获取冲压发动机喷管典型热负荷及其换热边界条件的前提下,构建一种纵向带肋超临界压力燃油冷却多通道结构,对比分析了燃油流动方向、燃油流量(68~204 g/s)、燃油进口温度(300~640 K)、燃油超临界压力(3~5 MPa)对通道内超临界压力燃油的流动和换热特性影响。结果表明:超临界压力燃油消耗275 g/(s·m^(2)),就能够将喷管壁面最高温度由2986 K降低到1200 K以下;燃油与喷管内燃气流动方向一致时,可充分利用燃油换热的入口段效应,降低喷管入口壁面高温,喷管进出口壁面温差减小,轴向热应力减小;燃油质量流量增加,冷却通道内表面传热系数提高,冷却效果提高,但是燃油压降逐渐增加;燃油进口温度过高会使通道近壁处流体的热扩散系数急剧增大,造成传热恶化,存在某一最佳进口温度使燃油压降最低;在燃油进口温度较低的情况下,燃气侧壁面温度和燃油压降随燃油压力变化不敏感。On the premise of obtaining typical heat load of the ramjet nozzle and its heat transfer boundary conditions,a longitudinally ribbed supercritical pressure fuel cooling multi-channel structure was constructed,the effects of fuel flow direction,fuel flow(68—204 g/s),fuel inlet temperature(300—640 K),fuel supercritical pressure(3—5 MPa)on the flow and heat transfer characteristics of supercritical pressure fuel in the channel were compared and analyzed.The results showed that:the supercritical pressure fuel consumption was 275 g/(s·m^(2)),the maximum temperature of the nozzle wall can be reduced from 2986 K to below 1200 K;when the fuel and gas flow in the nozzle were in the same direction,the inlet section effect of the fuel heat exchange can be fully utilized to reduce the high temperature of the nozzle inlet wall,the temperature difference between the nozzle inlet and outlet walls was reduced,and the axial thermal stress can be reduced;the fuel mass flow increased,the surface heat transfer coefficient in the cooling channel increased,and the cooling effect improved,but the fuel pressure drop gradually increased;if the fuel inlet temperature was too high,the thermal diffusivity of the fluid near the channel wall increased sharply,resulting in heat transfer deterioration,then there was an optimal inlet temperature to minimize the fuel pressure drop;when the fuel inlet temperature was low,the gas side wall surface temperature and fuel pressure drop were not sensitive to the change of fuel pressure.

关 键 词：冲压发动机喷管 超临界压力燃油 换热特性 流动特性 燃油压降 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]