A novel double shell-passes multi-layer helically coiled tubes heat exchanger (DSMHCTHE) is proposed to improve the flow and heat transfer performance of the shell side. It was studied by using conjugate heat transfer numerical model. By changing coil diameter and pitch, the influence of coil torsion on the performance of the heat exchangers was investigated in the range of 0.0637–0.3183, and compared with the conventional multi-layer helically coiled tubes heat exchangers (MHCTHE). Two kinds of heat exchangers were optimized by using multi-objective optimization differential evolution algorithm. The results indicate that the coil pitch has a greater effect on the overall heat transfer coefficient, and the effects of coil pitch variations in the inner and outer helically coiled tubes follow different patterns. Compared with MHCTHE, the heat transfer rate of DSMHCTHE are increased by 13.9 %–19.1 %, the comprehensive performance is increased by 13.0 %–18.0 %, and the heat transfer entropy generation number and friction entropy generation number are lower. It shows that DSMHCTHE have better application potential as heat exchangers.

中文翻译：

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新型双壳程多层螺旋管换热器共轭传热数值模拟及多目标优化设计


提出了一种新型双壳程多层螺旋管换热器（DSMHCTHE）来改善壳程的流动和传热性能。采用共轭传热数值模型对其进行了研究。通过改变盘管直径和螺距，在0.0637~0.3183范围内研究盘管扭转对换热器性能的影响，并与传统多层螺旋管换热器（MHCTHE）进行比较。采用多目标优化差分进化算法对两种换热器进行优化。结果表明，盘管节距对总传热系数影响较大，且盘管节距变化对内外螺旋管的影响遵循不同的模式。与MHCTHE相比，DSMHCTHE的传热率提高了13.9%~19.1%，综合性能提高了13.0%~18.0%，传热熵产生数和摩擦熵产生数更低。这表明DSMHCTHE作为换热器具有更好的应用潜力。