预冷通道中超临界甲烷换热特性分析  

Analysis on heat transfer characteristics of supercritical methane in precooling channels

作　　者：王彦红 蒋雷 薛帅 李洪伟[1] 贾玉婷[1] WANG Yanhong;JIANG Lei;XUE Shuai;LI Hongwei;JIA Yuting(School of Energy and Power Engineering,Northeast Electric Power University,Jilin 132012,Jilin,China)

机构地区：[1]东北电力大学能源与动力工程学院,吉林吉林132012

出　　处：《化工进展》2024年第4期1690-1699,共10页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(52106196);吉林省教育厅科技项目(JJKH20220100KJ)。

摘　　要：为了研究甲烷预冷器的预冷性能,本文基于Realizable k-ε湍流模型开展了预冷通道中超临界甲烷换热特性数值研究。探究了甲烷压力和预冷器结构参数对换热的影响机制。讨论了通道截面温度场和流场特征,探究了离心力及二次流对换热的影响,分析传热过程熵产。考察了热加速对换热的影响,提出了新的热加速量纲为1因子和判别准则,综合离心力项和热加速项建立了换热关联式。结果表明:进口段热边界层低热导率引起传热恶化问题,离心力造成周向换热差别。通道截面出现较强二次流,其传热熵产显著。甲烷压力提高有利于抑制传热恶化且削弱离心力作用;预冷器外径增大会增强离心力且使传热恶化加剧。当热加速因子Ac高于8.19×10^(-7)时,热加速对传热恶化发挥作用。提出的换热关联式可以有效实现预冷通道中超临界甲烷的换热预测。In order to study the precooling performance of methane precooler,numerical research on heat transfer characteristics of supercritical methane in precooling channels were carried out based on Realizable k-εturbulence model.Influence mechanisms of methane pressure and precooler structural parameter on heat transfer were analyzed.Temperature field and flow field characteristics in the channel section were discussed,the effects of centrifugal force and secondary flow on heat transfer were explored,and the entropy generation in the heat transfer process was analyzed.The influence of thermal acceleration on heat transfer was investigated,and a new dimensionless factor and criterion for thermal acceleration were proposed.The heat transfer correlation was established by combining the centrifugal force term and the thermal acceleration term.The results show that the low thermal conductivity of thermal boundary layer in the inlet region causes the heat transfer deterioration,and the centrifugal force leads to the circumferential difference in heat transfer.The strong secondary flow appears in the channel cross-section,and the heat transfer entropy generation is significant.The increase in methane pressure is beneficial for suppressing the heat transfer deterioration and weakening the effect of centrifugal force.The increase in outer diameter of precooler will enhance the centrifugal force and exacerbate the heat transfer deterioration.When Ac exceeds 8.19×10^(-7),the thermal acceleration plays a role in the deterioration of heat transfer.The proposed heat transfer correlation can effectively predict the heat transfer of supercritical methane in precooled channels.

关 键 词：微通道 超临界甲烷 传热 离心力 熵产 数值分析 

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] TQ021[化学工程]