CAJ | 학술논문

为了研究底部加热多孔介质方腔内的自然对流传热，采用整体求解法对方腔内的温度场和流场进行了数值模拟计算，着重分析了瑞利数Ra对多孔介质方腔内自然对流换热特性的影响。计算结果表明：随着Ra数的逐渐增加，对流换热开始占主要作用，等温线变得扭曲；流线由逆时针单胞对流逐渐变化为正反两个双胞对流，流动出现分叉现象，温度场和流线相互对应。平均Nusselt也随之增大，换热效果得到增强。
위료연구저부가열다공개질방강내적자연대류전열，채용정체구해법대방강내적온도장화류장진행료수치모의계산，착중분석료서리수Ra대다공개질방강내자연대류환열특성적영향。계산결과표명：수착Ra수적축점증가，대류환열개시점주요작용，등온선변득뉴곡；류선유역시침단포대류축점변화위정반량개쌍포대류，류동출현분차현상，온도장화류선상호대응。평균Nusselt야수지증대，환열효과득도증강。
In order to study natural convection heat transfer in square porous medium heated from below, numerical simulation calculation is carried out to analyze the temperature and velocity field of square cav-ity using whole-field solution.The effects of Ra number on the natural convection heat transfer charac-teristics in square enclosure filled with porous medium are analysed especially.The results of the study show that with the increase of Ra,heat convection begans to play the main role and the temperature con-tour becomes distorted.The streamline changes gradually from the counterclockwise single cellular con-vection to the positive and negative two twin convection.The flow bifurcation occurs,the temperature field and the streamline correspond to each other.The average Nusselt number increases and the effect of heat transfer gets enhanced.