Abstract This work describes the recent progress in the improvement of heat transfer through microscale facing steps. This analysis includes previous studies that aimed to improve heat transfer with and without hybrid nanofluids. This review presents the experimental and numerical results on the usage of hybrid nanofluids. Furthermore, this work introduces the use of backward-facing step (BFS), forward-facing step (FFS) and microscale steps with different flow regimes and working fluids. This study reveals an increase in heat transfer by utilizing hybrid nanofluids as a working fluid and an improvement in the coefficient of heat transfer when the nanoparticle volumes and concentrations of hybrid nanofluids increase. This work points out the studies on hybrid nanofluids over BFS and FFS, describes various nanoparticles used on the basis of thermal conductivity and shows the improvement in the rate of heat transfer. This study also outlines the discussion and future direction of the current review.

中文翻译：

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混合纳米流体流动和后退和前进步骤的热传递：综述

摘要 这项工作描述了通过微尺度饰面步骤改善传热的最新进展。该分析包括先前旨在改善使用和不使用混合纳米流体的热传递的研究。本综述介绍了使用混合纳米流体的实验和数值结果。此外，这项工作介绍了使用后向阶梯 (BFS)、前向阶梯 (FFS) 和具有不同流态和工作流体的微尺度阶梯。该研究揭示了通过将混合纳米流体用作工作流体来增加传热，以及当混合纳米流体的纳米颗粒体积和浓度增加时传热系数的提高。这项工作指出了在 BFS 和 FFS 上对混合纳米流体的研究，描述了基于热导率使用的各种纳米粒子，并显示了传热速率的改进。本研究还概述了当前审查的讨论和未来方向。