Liquid-liquid slug flow in ribbed micro-channel heat sinks: Hydrodynamic-thermal analysis

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences Pub Date : 2025-10-07 DOI:10.1016/j.ijthermalsci.2025.110368

Pardis Pakzadi Abnavi, Reza Kamali, Mohammad Reza Paydari

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引用次数: 0

Abstract

The hydrothermal efficiency of liquid-liquid slug flow in novel configurations for fillet-free and filleted ribbed micro-channels was numerically investigated. This study addressed the following novel configurations: semi-circular ribbed micro-channel (MCHS-CR), semi-elliptic ribbed micro-channel (MCHS-ER), semi-circular ribbed micro-channel with filleted corners (MCHS-CR-FC), and semi-elliptic ribbed micro-channel with filleted corners (MCHS-ER-FC). effects of rib shapes and filleted corners on the hydrodynamic-thermal behavior of slug flow in micro-channels were studied at different inlet velocities. Adding ribs significantly enhanced heat removal compared to a smooth micro-channel (MCHS-S) in the presence of droplet two-phase flow. Heat transfer enhancement, caused by secondary flow generation and improved fluid advection, increased with rising flow velocity. Based on the results, incorporating fillets at the rib corners led to a significant enhancement in heat transfer, with a slightly escalated pressure drop. To assess the simultaneous influences of increasing the Nusselt number and the pressure drop, a performance evaluation criterion (PEC) was used. In comparison to the MCHS-CR and MCHS-ER configurations, the MCHS-CR-FC and MCHS-ER-FC designs raised the Nusselt number by about 6.1–8.3 % and 3.5–7 %, and improved about PEC 6–6.9 % and 3–6.2 %, respectively. Furthermore, the MCHS-ER-FC configuration, due to its superior circulation strength within the droplets, droplet intervals, and rib zones, yielded the greatest reduction in wall temperature and the highest heat transfer performance among all configurations studied.

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肋状微通道散热器中的液-液段塞流：流体动力学-热分析

对无圆角和带圆角肋微通道新型构型液液段塞流的热液效率进行了数值研究。本研究研究了以下新型结构：半圆形肋形微通道（MCHS-CR）、半椭圆形肋形微通道（MCHS-ER）、带圆角的半圆形肋形微通道（MCHS-CR- fc）和带圆角的半椭圆形肋形微通道（MCHS-ER- fc）。研究了不同进口速度下，肋型和圆角对微通道段塞流动热特性的影响。与存在液滴两相流的光滑微通道（mch - s）相比，添加肋显著增强了热量的去除。由于二次流的产生和流体平流的改善，传热增强随着流速的增加而增加。根据研究结果，在肋角处加入圆角可以显著增强传热，同时压降略有上升。为了评估同时增加努塞尔数和压降的影响，采用了性能评价准则（PEC）。与MCHS-CR和MCHS-ER结构相比，MCHS-CR- fc和MCHS-ER- fc结构的Nusselt数分别提高了6.1 ~ 8.3%和3.5 ~ 7%，PEC分别提高了6 ~ 6.9%和3 ~ 6.2%。此外，由于MCHS-ER-FC结构在液滴、液滴间隔和肋区内具有优越的循环强度，因此在所有研究结构中，壁面温度的降低幅度最大，传热性能最高。

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来源期刊

International Journal of Thermal Sciences 工程技术-工程：机械

CiteScore

8.10

自引率

11.10%

发文量

531

审稿时长

55 days

期刊介绍： The International Journal of Thermal Sciences is a journal devoted to the publication of fundamental studies on the physics of transfer processes in general, with an emphasis on thermal aspects and also applied research on various processes, energy systems and the environment. Articles are published in English and French, and are subject to peer review. The fundamental subjects considered within the scope of the journal are: * Heat and relevant mass transfer at all scales (nano, micro and macro) and in all types of material (heterogeneous, composites, biological,...) and fluid flow * Forced, natural or mixed convection in reactive or non-reactive media * Single or multi–phase fluid flow with or without phase change * Near–and far–field radiative heat transfer * Combined modes of heat transfer in complex systems (for example, plasmas, biological, geological,...) * Multiscale modelling The applied research topics include: * Heat exchangers, heat pipes, cooling processes * Transport phenomena taking place in industrial processes (chemical, food and agricultural, metallurgical, space and aeronautical, automobile industries) * Nano–and micro–technology for energy, space, biosystems and devices * Heat transport analysis in advanced systems * Impact of energy–related processes on environment, and emerging energy systems The study of thermophysical properties of materials and fluids, thermal measurement techniques, inverse methods, and the developments of experimental methods are within the scope of the International Journal of Thermal Sciences which also covers the modelling, and numerical methods applied to thermal transfer.