A review of experimental studies on flow boiling instabilities mitigation through geometrical modifications

Abstract

• The number of publications focused on the flow boiling instabilities is increasing in the last decades. • Most of the studies are based on microchannel and pin fin structures. • The integration of combined geometries is a promising approach to further improve the efficiency and reliability of flow boiling technology. Flow boiling technology is considered one of the most promising cooling solutions for high power microelectronics. However, flow boiling instabilities cause serious reliability problems that hinder large scale commercial use of this technology. Extensive experimental research has been carried out in the last years to mitigate these issues, focusing on geometrical aspects, surface modification, wettability, working fluid, or active control strategies, among others. Nevertheless, despite the relevance of geometrical aspects, none of the studies conducted a comprehensive review on geometrical structures and their instabilities mitigation effect. This review aims to provide constructive insights into relevant studies about experimental flow boiling geometrical enhancements and their impact on instabilities mitigation. It focuses on pin-fin arrays, most of the microchannel structures, inlet restrictors, and combined geometries. Firstly, every geometrical option is analysed in detail, summarizing experimental works in terms of geometry tested, operating parameters, and instabilities improvement. Secondly, a graphical overview is performed aimed at identifying research gaps and tendencies. This study found that significant progress has been made in geometric mitigation of flow boiling instabilities, and several advanced methodologies have been proposed to improve the reliability of flow boiling technology. The integration of various geometric configurations is a promising avenue, but further research is required to reach a widely accepted solution.

Topics & Concepts