Thermal Performance of an Axially Grooved Heat Pipe Subjected to Multiple Heating Sources

Abstract

Listen

Translate article

An experiment of axial temperature test for a heat pipe subjected to discrete heating sources is performed for deep understanding of the thermal characteristics of axial dovetail grooved heat pipe during the unsteady and steady state. The influences of heating length, heating source position, source configurations and incline angle on the temperature profiles, heat transfer limit of the heat pipe under single heating source and multiple heating sources are examined and analyzed. As can be seen from the experiment results, the heating source shows a pivotal role in the transient characteristics of the dovetail grooved heat pipe. The heated zone of the heat pipe shows higher temperature level than that of the non-heated zone, and there is a sharp temperature variation at the transition region of the heating zone and non-heating zone. When heat is imposed at the front end of heat pipe, a dramatic increase of temperature appears soon after the heating power has reached its heat transport limitation. And this limitation can still be increased when the heating source is imposed close to the cooling section as the distance between the heating source and the cooling section decreases. Increase of heating length narrows the gap of the temperature between evaporator section and condenser section, and hence lead to lower thermal resistance, higher thermal conductivity, and superior heat transport performance. Owing to the gravity assistance on the backflow fluid in microgrooves, better thermal performance can be observed when the heat pipe works under incline state than that under horizontal state.