冷却条件下管内超临界压力CO2对流换热研究  

CONVECTION HEAT TRANSFER OF CO_2 AT SUPERCRITICAL PRESSURES IN TUBE DURING COOLING

作　　者：赵陈儒[1] 姜培学[1] 

机构地区：[1]热科学与动力工程教育部重点实验室 清华大学热能工程系,北京100084

出　　处：《工程热物理学报》2009年第3期456-460,共5页Journal of Engineering Thermophysics

基　　金：国家863计划项目(No.2006AA05Z416);教育部科学技术重大项目(No.306001)

摘　　要：本文用数值计算和实验测量结合的实验方法对冷却条件下超临界压力二氧化碳在细圆管内(D_(in)=2 mm)的局部对流换热进行了实验研究。结果表明,冷却条件下超临界二氧化碳局部对流换热系数在流体温度略高于准临界温度时达到峰值.本文还对该过程进行了数值模拟,比较了不同湍流模型的计算结果,根据数值模拟提供的信息分析了影响冷却条件下超临界压力二氧化碳换热的主要因素和物性变化对换热的影响。The local heat transfer coefficients for carbon dioxide at supercritical pressures in small vertical tube under cooling condition were determined through a combination of experiments and numerical simulations. The local heat transfer coefficients vary significantly along the tube when the CO2 bulk temperatures are in the near-critical region. Numerical simulations were performed using several k-ε turbulence models including the RNG k-ε model and three low-Reynolds number eddy viscosity turbulence models. A better understanding of convection heat transfer of CO2 at supercritical pressures in a vertical small tube during cooling has been developed based on the information generated by the simulation on the detailed flow and turbulence fields.

关 键 词：超临界压力二氧化碳 细圆管 冷却 对流换热 

分 类 号：TK124[动力工程及工程热物理—工程热物理]