【摘要】 针对热电冷综合利用系统中的集热箱,抽象出一个受限方腔内两圆管的强制对流换热问题并进行了数值研究.分别对不同雷诺数Re以及不同管间距s的情况进行数值模拟.结果表明,Re较小时流体流动与换热随时间变化,最后趋于一个稳定的对称状态;当Re增加至一定值后,流体流动与换热随时间变化,处于非对称状态.随着Re的增加,流动出现振荡,流体与圆管壁面换热不断增强,计算得到的解从定态解发展为周期性振荡解、多倍周期振荡解,最终发展为混沌.对于不同管间距s,当Re≤150时,管子间距的不同对受限腔内的换热影响不是很大;当200≤Re<300时,管间距s对于流动与换热有较大的影响;但当Re≥300之后,管间距s对换热影响较小.更多还原

【Abstract】 Numerical method was used to study the heat transfer of heat collector of a domestic heating power cooling integrated utilization system(DHPCIUS).The unsteady forced convection of two heated horizontal cylinders confined in a 2-D squared enclosure was studied and abstracted to a model by using the DHPCIUS.The simulations were carried out under different Reynolds number Re and cylinders spacing s.The results show that when the Re is smaller,the fluid flow and heat transfer finally tend to a stable and symmetrical state.When the Re increases to a certain value,the fluid flow and heat transfer change over time,being in an asymmetric state.The flow fluid and the heat transfer on the cylinders surfaces are enhanced when the Re increases.The calculations got a stable solution,a periodic oscillation and a direct entering into chaos along with the increase of Re.The cylinder spacing s has a little influence on the flow and heat transfer when Re≤150,while has a great influence on the flow and heat transfer when 200≤Re<300.But when Re≥300,the cylinder spacing affects less on heat-exchange.更多还原