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为了研究国标中规定的板管间隙对管壳式换热器壳程流动与传热的细观影响,运用CFD软件建立管壳式换热器壳程周期模型并进行了数值计算。分析结果表明,当板管间隙小于等于国标Ⅰ级管束规定的最大间隙0.35 mm时,间隙漏流影响的范围很小,折流板之间流体的流动趋近于理想横流,传热效果好;当间隙大于等于国标Ⅱ级管束规定的最大间隙0.5 mm时,漏流产生的漩涡强度变大,折流板之间流体的流动趋近于纵向流,从而导致换热管的整体传热性能下降;在折流板背面存在一个换热性能最差的截面,该截面与折流板之间的距离随着Re和间隙的增大而增大。
In order to study the effect of plate gap on the flow and heat transfer of shell and tube heat exchanger shell and tube as stipulated in the national standard, CFD software was used to establish shell and shell cycle model of shell and tube heat exchanger and numerical calculation. The results show that when the plate gap is less than or equal to the maximum clearance of 0.35 mm specified by the national standard class Ⅰ bundle, the influence of the gap leakage is very small. The fluid flow between the baffles approaches the ideal cross flow and the heat transfer effect is good. When the clearance is greater than or equal to the maximum clearance 0.5 mm specified by the national standard grade II tube bundle, the eddy current intensity generated by the leakage current becomes larger and the fluid flow between the baffles approaches the longitudinal flow, resulting in a decrease in the overall heat transfer performance of the heat exchange tube ; There is a cross-section of the baffle on the worst heat transfer performance of the cross-section of the baffle with the distance between the Re and gap increases.