Numerical investigation of Hybrid Wick Structure Effect on Thermal Performance of a Thin Flat Heat Pipe

Due to the volume and mass limits of the small electronic devices, thin flat heat pipes are an ideal solution for the efficient transfer and dissipation of heat. The performance of thin heat pipes is heavily dependent on wick structure characteristics. In this research, the thermal performance of thin flat heat pipes (TFHPs) with hybrid and grooved wick for different heat inputs were studied numerically, and their heat transfer characteristics were compared. The trends of various parameters such as wall temperature, maximum axial velocity, mass transfer at the liquid-vapor interface, system pressure, and thermal resistance on the thermal performance of the TFHPs with hybrid and groove wicks were analyzed. The numerical simulation has been done using a two‐dimensional unsteady incompressible laminar flow. Results indicated that the evaporation section temperature of hybrid wick TFHP is significantly lower than the corresponding value of grooves heat pipe. It was also observed that with increasing heat input, thermal resistance of hybrid wick TFHP decreased and it has an excellent performance compared to the grooved wick. For heat fluxes of 10, 20, and 30 W, the performance of the TFHP with hybrid wick compared to grooved wick is improved by 3.59%, 20.38%, and 28.57%, respectively. Therefore, the thermal performance improvement of the TFHP with the hybrid wick was more significant. This improvement is more considerable for higher heat fluxes.