Abstract:

Two indicators were proposed to evaluate the performance of H-type finned tube, i.e. the heat exchange per unit mass and the recovered heat transfer per unit power of the fan, and a selection method was derived to determine the structure parameters for the H-type finned tube. Numerical studies were performed to investigate the H-type finned tube with different fin widths and pitches. The results show that with the increase of fin width, the heat transfer per unit mass of finned tube increases first and then deceases, and when this indicator reaches the maximum value with different fin pitches, the fin width is between 55 and 60 mm. With the increase of fin width, the recovered heat transfer per unit power of the fan also increases first and then deceases, but when this indicator reaches the maximum value with different fin pitches, the fin width increases gradually. The fin pitch has the minimum value when both indicators reach the maximum value, so the two indicators as well as the manufacturing process and fouling characteristics should be taken into consideration for selecting the structure parameters.

Key words: H-finned tube, heat transfer, flow, comprehensive performance, numerical simulation

摘要：

提出了单位质量鳍片管换热量与引风单位耗功所回收热量两个评价H型鳍片管性能的主要指标,给出了H型鳍片管结构参数选取的方法。通过对不同鳍片宽度与鳍片间距的H型鳍片管进行数值研究发现,单位质量鳍片管换热量随鳍片宽度的增加先增加后降低,并且在不同鳍片间距下,该指标达到最大值时所对应的鳍片宽度均在55～60 mm;引风单位耗功所回收热量随鳍片宽度的变化也呈现出先增加后降低的趋势,但在不同鳍片间距下,该指标达到最大值时所对应的鳍片宽度逐渐增加。当两个指标达到最大值时,所对应的鳍片间距均为最小值,因此,在选取鳍片管结构参数时,应根据单位质量鳍片管换热量与引风单位耗功所回收热量两个指标并兼顾制造工艺与热量回收区域的积灰状况进行选取。

关键词: H型鳍片管, 传热, 流动, 综合性能, 数值模拟