Abstract

The present study investigates the characteristics and heat transfer performance of a flat heat pipe (FHP) heat spreader with various wick structures. A flat heat pipe heat spreader exemplifies successful heat transfer applications for highly efficient devices in space, energy technology, electronics cooling etc. The present experimental and simulation results reveal the heat transfer characteristics of a flat heat pipe with various parameters in the range of 5~20 W. In the experimental study, eight different wick structures were evaluated in order to find the optimum wick, and various working fluids such as water, acetone, ethanol, and TiO₂-nanofluids were used since the main driving force comes from the capillary force generated in the wick. The 0.1%-TiO₂ nanofluidic flat heat pipe system exhibited the best heat spreading performance. In the present study, a simulation based on the thermal resistance network with special modified spreading resistance was conducted. The simulation results show a reasonable agreement with the experimental results.

Key words: Heat pipe, heat transfer, heat spreader, thermal management, nanofluid.