Experimental Study on the Evaporation and Condensation Heat Transfer Characteristics of a Vapor Chamber

Yanfei Liu,Mengchen Zhang,Chaoqun Shen,Feng Yao,Xiaotian Han

doi:10.3390/en12010011

Abstract

A vapor chamber can meet the cooling requirements of high heat flux electronic equipment. In this paper, based on a proposed vapor chamber with a side window, a vapor chamber experimental system was designed to visually study its evaporation and condensation heat transfer performance. Using infrared thermal imaging technology, the temperature distribution and the vapor–liquid two-phase interface evolution inside the cavity were experimentally observed. Furthermore, the evaporation and condensation heat transfer coefficients were obtained according to the measured temperature of the liquid near the evaporator surface and the vapor near the condenser surface. The effects of heat load and filling rate on the thermal resistance and the evaporation and condensation heat transfer coefficients are analyzed and discussed. The results indicate that the liquid filling rate that maximized the evaporation heat transfer coefficient was different from the liquid filling rate that maximized the condensation heat transfer coefficient. The vapor chamber showed good heat transfer performance with a liquid filling rate of 33%. According to the infrared thermal images, it was observed that the evaporation/boiling heat transfer could be strengthened by the interference of easily broken bubbles and boiling liquid. When the heat input increased, the uniformity of temperature distribution was improved due to the intensified heat transfer on the evaporator surface.

Highlights

Vapor–liquid phase change has always been of great interest in a wide range of technical applications, such as electronic cooling [1,2], chemical processes [3,4], space thermal control [5,6], microfluidic preparation [7,8], biomedical engineering [9,10], etc
As a typical technical application, a vapor chamber is recognized as one of the most effective ways to achieve uniform heat dissipation in a confined space due to its good temperature uniformity, flexible system compatibility, and high thermal transport capacity [11,12]. This advanced technology has been successfully applied in waste heat recovery [13], solar thermal utilization [14], thermal management of data centers [15], electronic component cooling [16], etc
The results demonstrated better temperature uniformity and smaller thermal resistance compared with traditional vapor chambers

Summary

Introduction

Vapor–liquid phase change has always been of great interest in a wide range of technical applications, such as electronic cooling [1,2], chemical processes [3,4], space thermal control [5,6], microfluidic preparation [7,8], biomedical engineering [9,10], etc. As a typical technical application, a vapor chamber is recognized as one of the most effective ways to achieve uniform heat dissipation in a confined space due to its good temperature uniformity, flexible system compatibility, and high thermal transport capacity [11,12]. This advanced technology has been successfully applied in waste heat recovery [13], solar thermal utilization [14], thermal management of data centers [15], electronic component cooling [16], etc. Liu et al [22] proposed a high thermal performance vapor chamber with a leaf-vein-like wick structure and a thermal resistance of about

Methods

Results

Conclusion