Experimental Investigation of Bendable Heat Pipes

Abstract

Heat pipes are highly conductive heat transfer devices. They use the latent heat of the working fluid for efficient heat transfer over a very small temperature drop. They have been a subject of numerous studies since the early 1950s and are commercially available in a variety of forms. This thesis is an investigation of the effect bending has on the performance of heat pipes. Flexible and pre-bent heat pipes have been studied and successfully demonstrated in the past. Bendable heat pipes, which can be bended after fabrication as needed are a novel device developed during this study. The effect of bending on temperature drop, performance and performance limits was investigated. The heat pipes used for testing were made using oxygen free copper for the container and water as the working fluid. The wick was made from sintered copper felt and provided the post fabrication bendability feature of these heat pipes. The concept of copper equivalence to compare disparate data is also developed and explained. It is used to benchmark the test data against copper conductivity.