复杂几何结构腔体内冷水自然对流传热数值模拟

Natural convection of water near its density maximum in cavity with complex geometry structure

利用有限容积法对复杂几何结构异形腔体内具有密度极值的冷水自然对流传热进行了一系列数值模拟,获得了多种异形腔体内不同密度倒置参数和Rayleigh数下的流场和温度场、壁面局部和平均Nusselt数等的变化规律。结果表明:密度倒置参数对流场结构、壁面局部Nusselt数分布和平均Nusselt数影响较大;径深比较小时,流动较强,随着径深比的增大,流动减弱;相同条件下,改变外壁面几何结构,封闭腔体内温度场、流场及壁面传热特性都有不同程度的变化。

A series of numerical simulations on natural convection of water near its density maximum in a cavity with complex geometry structure was performed using finite volume method.The flow and thermal fields and the variation law of local and average Nusselt on the wall with the Rayleigh number at different density inversion parameters were obtained.The results show that the effect of density inversion parameter on the flow structure and heat transfer characteristic is significant.The flow intensity becomes weak with the increase of the aspect ratio.Under the same conditions,the flow,thermal fields and heat transfer rates vary in degree with the geometry structure of the out wall changes.