二维方腔非稳态自然对流数值模拟研究  

TWO DIMENSIONAL NUMERICAL STUDY OF TRANSIENT NATURAL CONVECTION IN RECTANGULAR ENCLOSURE

作　　者：杨卫卫[1] 何雅玲[1] 徐超[1] 陶文铨[1] 

机构地区：[1]西安交通大学能源与动力工程学院多相流国家重点实验室,陕西西安710049

出　　处：《工程热物理学报》2004年第2期281-283,共3页Journal of Engineering Thermophysics

基　　金：国家973重点基础研究规划资助项目(No.G2000026303);国家自然科学基金资助项目(No.50276046)

摘　　要：本文针对二维方腔中非稳态自然对流过程进行了数值研究,方腔一侧被等温冷却,另一侧受到三块热板脉动加热,热板温度满足两种不同规律,脉动周期0.01 s<τ<500 s,脉动大小0<α<0.40,所研究的自然对流问题取Ra=106,工质为空气(Pr=0.70)。研究结果表明:方腔中冷板瞬时对流换热量与相应稳态时有很大差异;在一定条件下,热板温度脉动周期和脉动量对冷板的换热量均有很大的影响。A two dimensional model of the transient natural convection in a cavity is studied numerically. The system is cooled isothermally from the right and heated from the left by three hot pieces. The temperature of hot pieces are heating with two types of excitations. In the first type, the temperature is varied sinusoidally in time while in the second, it varies with a pulsating manner. For each type of excitation, the effect of the amplitude of the excitating temperature(0 < a < 0.4) and its period(0.01 s< τ < 500 s) on heat transfer is studied. For the present study, the Rayleigh number is 106 and the working fluid is air(Pr = 0.70). The results obtained show that the transient heat transfer evacuated through the cold face of the enclosure is highly different from the steady case. In addition, it is demonstrated that the amplitude of the excitating temperature and its period have great effects on heat transfer.

关 键 词：自然对流 脉动加热 数值模拟 二维方腔 非稳态 

分 类 号：TK124[动力工程及工程热物理—工程热物理]