ADVANCES AND OPPORTUNITIES IN BUBBLE-ACTUATED CIRCULATING HEAT PIPE (BACH)

Niro Nagai,Hideo Shingu,Toyoji Onishi,Akikazu Iwamoto

doi:10.5098/fhp.v1.2.3005

Abstract

Bubble-Actuated Circulating Heat pipe (BACH) is a new type of heat pipe, which transport heat mainly by liquid circulation induced by bubble buoyancy force. BACH is strongly expected to have new features which may overcome defects on conventional heat pipes. Heat transport rates of BACH under bottom heat mode were experimentally measured under various conditions. The result shows that the heat transport rates of BACH is the order of several hundred watt and its effective thermal conductivity is 5 ~ 20 kW/(m･K). Finally, several candidates for BACH’s future application are introduced.

Highlights

Heat pipe is one of heat transport devices which can transport heat more than that by heat conduction and operates without power input
Conventional heat pipes can be largely classified into two types: one is wick-type heat pipe (Ohshima et al, 1979) including two-phase thermosiphon type (Ueda et al, 1988, Koito et al, 2006), and the other is self-oscillation-type heat pipe (Nishio et al, 1999, Tong et al, 2001, Suzuki, 2003, Miyakawa et al, 2005, Qu and Ma, 2007) including capillary loop type (Maydanik, 2005, Launay et al, 2007)
As mentioned in INTRODUCTION, there were misgivings the heat transport rate of Bubble-Actuated Circulating Heat pipe (BACH) is very little compared to conventional type heat pipe, since dominant operating mechanism of BACH is considered to be sensible heat transport

Summary

Introduction

Heat pipe is one of heat transport devices which can transport heat more than that by heat conduction and operates without power input. Heat pipe have played important roles for thermal control system of electronic devices, efficient use of natural energy such as geothermal energy, and so on (Ohshima et al, 1979, JAHP, 2001). Forcedoscillating-flow heat-pipes (Nishio and Tanaka, 2002), so called as “dream pipe”, have high performance of heat transport, but it needs power input for oscillating liquid inside. Wick-type and self-oscillation-type heat pipes have been eagerly researched and developed for practical use. There are still defects on these two-types of conventional heat pipes as follows

Objectives

Methods

Results

Discussion

Conclusion