【作者】 马军； 赵红霞； 韩吉田；

【Author】 MA Jun1,ZHAO Hongxia1,HAN Jitian1 (1 School of Power and Energy,Shandong University,Jinan250061,Shandong,china)

【机构】 山东大学能源与动力工程学院；

【摘要】 利用二维轴对称模型对在横向内肋圆管内流动的具有较大Pr的水-乙二醇溶液的强化传热和流动特性进行了数值分析。在表面等温的条件下,利用Fluent6.2研究水-乙二醇溶液在圆管某段周期性流动的特性,并且计算得到平均摩擦系数和传热系数。研究了不同的肋片高度e和节距p对强化传热的影响,结果发现与具有小Pr的空气和水不同,水-乙二醇溶液没有像空气那样存在确定的e/d临界值,管内摩擦系数和肋高直径比e/d、肋高节距比p/d以及Re的值可以利用一个等式进行关联。而且不能利用计算空气的努塞尔数时所采用的公式来确定其与Re,e/d和p/d的关系。更多还原

【Abstract】 The enhanced heat transfer and flow of water-glycol mixture with high Pr in transversely ribbed circular tubes was numerically investigated with a 2D axisymmetric model.A pitch long section was chosen and periodic flow with isothermal surface condition within this tube section was computed with Fluent 6.2.The mean friction factor and heat transfer data are obtained.The influence of different rib height and rib pitch on the enhanced heat transfer and flow behavior was studied.The friction factor was well correlated with e/d,p/d and Re with one equation,which is clearly different from water or air with small Pr.No critical e/d,which exists for air,was found for water-glycol mixture.The correlation of Nusselt number with Re,e/d,p/d cannot be correlated with similar equations used for air.更多还原