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为分析前排绕流扰动对后排管换热及阻力的影响规律,以4列多排(2~10)管束为研究对象,建立稳定的热态流场,采用错列及顺列2种方式,分析传热及流动特性在不同管排数下的变化规律;定量分析管排数对阻力特性的影响规律,定义了管排阻力修正系数,并根据实验数据给出了其在不同管排数下的取值;根据场协同理论定义了相对场协同率的概念,用以表征不同管排数下其总体换热效率相对实际最大换热的比值。研究结果表明,管间绕流为管束换热器管排影响规律的主要原因,10排及以上管束流场均匀,管间绕流影响最小,场协同角较小,10排以内采用管排系数进行修正。
In order to analyze the influence law of front row flow disturbances on the heat transfer and resistance of the rear row of tubes, four pairs of multi-row (2 ~ 10) tube bundles were selected as the research object to establish a stable hot flow field. The regularity of heat transfer and flow characteristics under different tube row numbers was analyzed. The influence rule of tube row number on the resistance characteristics was quantitatively analyzed. The coefficient of tube row resistance correction was defined. Based on the experimental data, According to the theory of field synergy, the concept of relative field synergy rate is defined to characterize the ratio of the overall heat exchange efficiency to the actual maximum heat transfer under different tube row numbers. The results show that the inter-pipe flow is the main reason for the influence of the tube bank heat exchanger. The flow field of the tube bundle of 10 rows and over is the least, and the influence of the flow around the pipe is the least, and the field synergy angle is small. Correct.