【摘要】 通过实验研究了垂直矩形窄通道内小尺寸加热元件在助流和反流条件下对流体的热传过程,详细探讨了混合对流的换热特性,并给出一系列实验关联式,用以计算混合对流条件下的换热率。当Re_L>2500时,无论助流或反流均不受Ra_L^*的影响;当Re_L<350时,对于助流,其换热率与Ra_L^*0.065成正比;在350<Re_L<2500时,浮升力的影响将增强换热,总之,在浮升力开始起作用的情况下,若继续使用受对流关联式,势必大大低估换热率。更多还原

【Abstract】 Measurements were made of heat transfer rates from a small-size heater to liquid flow in vertical narrow channel both for aiding and opposing flow conditions Heat transfer characteristics of mixed convection were examined in detail.A set of correlations is presented to predict mixed convection heat transfer rates,which may be considerably underestimated if forced convection correlations are used for calculation更多还原