Abstract In the present study, the effects of rotary tubes and magnetic-induced nanofluid on heat transfer characteristics of a compact heat exchanger are individually investigated. Two-phase Eulerian model is employed to predict the hydrothermal and entropic characteristics of Fe3O4/water ferrofluid in the heat exchanger. Results indicate that utilizing each rotary tubes and magnetic field method can improve the energy and exergy efficiencies of the compact heat exchanger under specific circumstances by forming different types of secondary flow. It is found that employing each method individually can increase the maximum heat transfer rate by more than 60%. In comparison with methods like passive vortex and swirl generators, subtle pressure drop and entropy generation is observed in the new proposed methods since no additional obstacles were employed. Results also reveal that 12.5% of the possible maximum energy can be regenerated along with a 3.5% increase in the exergy efficiency of the heat exchanger at low Reynolds numbers by employing each method.

中文翻译：

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磁致纳米颗粒和旋转管用于改善紧凑型换热器的能量和热能性能

摘要 在本研究中，分别研究了旋转管和磁诱导纳米流体对紧凑型换热器传热特性的影响。采用两相欧拉模型预测换热器中Fe3O4/水铁磁流体的热液和熵特性。结果表明，在特定情况下，利用各旋转管和磁场方法可以通过形成不同类型的二次流来提高紧凑型换热器的能量和火用效率。发现单独采用每种方法可以将最大传热率提高60%以上。与被动涡流和旋流发生器等方法相比，在新提出的方法中观察到微妙的压降和熵的产生，因为没有采用额外的障碍。结果还表明，通过采用每种方法，在低雷诺数下，12.5% 的可能最大能量可以再生，同时热交换器的火用效率增加 3.5%。