摘要
通过3种不同结构脉动热管的可视化实验,研究管内工质的运行机理与传热特性。另外,在流型和流向研究的基础上,对脉动热管进行结构改进,以实现工质稳定的单向循环流动。实验结果表明:在不同工作条件下,流型会出现塞状流、混合流和环状流,流向则会出现脉动流和循环流,流型和流向具有自适应传热量变化的特性;两种改进型脉动热管,一种设计成内径交错变化,一种设计成立体环型结构,具有更宽的循环流工作范围和更好的传热性能。
A series of visual experiments are performed on three types of closed-loop pulsating heat pipes （PHPs）, intending to investigate the operational mechanism and the heat transfer characteristics of the working fluid. On the basis of the foregoing experimental study of flow patterns and flow directions, two improved PHPs are developed to achieve reliable circulation of the working fluid. The experiment results indicate that there might exist three flow patterns, i. e. bubble-liquid slug flow,semi-annular flow and annular flow, corresponding to different working conditions. In terms of the flow directions, there might exist local oscillatory flow and bulk circulatory flow in a PHP. And for a given geometry and an adequate fill ratio, the PHPs have the self-adjusting characteristic for the flow patterns and flow directions to meet the demands of the increasing heat input. The two improved PHPs, one with alternately varying channel diameter, and the other with 3D loop configuration, operate in the circulatory manner across a wide range of heat input and exhibit higher thermal performance.
出处
《现代化工》
EI
CAS
CSCD
北大核心
2008年第11期68-72,共5页
Modern Chemical Industry
基金
国家自然科学基金重点项目(50736002)
关键词
脉动热管
运行机理
传热特性
结构改进
pulsating heat pipe
operational mechanism
heat transfer characteristic
structure improvement
