冷却塔填料布置方式对热力性能的影响

Impact of non-uniform fill layouts of the cooling tower on thermal performance

相对于填料均匀布置,不均匀布置对冷却塔性能有改善作用。为了探讨淋水填料不同布置方式对冷却塔热力特性和阻力性能的影响,在冷却塔内部填料原有的等高等间距布置基础上,进行不等间距及不等高布置的优化设计;建立3种布置方式的三维数值模型,比较其在多种工况下的热力性能;选择实际运行中4种代表性工况,对比分析数值模拟结果和实测数据。结果表明:相对于填料均匀布置方式,不等高和不等间距布置均能不同程度提高冷却塔的换热性能,使得温降增加0.7~1.0℃;与不等高布置相比,不等间距布置不仅增加了塔内外围冷却效果,对塔内中心区冷却效果的提升也更加明显;综合多种工况,不等间距布置方式总体温降比不等高布置增加0.2℃左右;数值模拟结果与实验结果整体偏差不大,趋势相同,可以反映冷却塔实际运行情况,可用于指导冷却塔填料布置设计。

Compared with uniform fill layouts, non-uniform fill layouts show an improvement on the performance of the cooling tower. In order to investigate the influence of fill layouts on thermal performance and drag characteristic of the cooling tower, based on the original fill layouts of equal height and equal interval, optimization design of unequal height and unequal interval was carried out on the filler of the cooling tower. The threedimensional numerical models of three kinds of fill layouts were established to compare their performance under different working conditions. Then, four typical operating conditions in practice running were selected to compare the numerical simulation results and the measured data. The results show that, compared with the uniform fill layouts, both the unequal interval fill layouts and the unequal height fill layouts can improve the heat transfer performance of the cooling tower, which make the temperature drop increased by 0.7-1.0 ℃. Besides, compared with the unequal height fill layouts, the unequal interval fill layouts not only improve the cooling effect of the outside region of the cooling tower, but also significantly enhance the cooling performance of the central area of the cooling tower. Integrate various working conditions, the temperature drop of the unequal interval fill layouts increases by about 0.2℃compared with the unequal height fill layouts. In addition, the numerical simulation results are consistent with the experimental data and both have the same trends. It indicates that the numerical simulation can reflect the actual operation of the cooling tower, and can be used to guide the design of the fill layouts.