Thermal Management Of High-power LEDs Based On Integrated Heat Sink With Vapor Chamber

An integrated heat sink with vapor chamber?IHSVC?was developed in the study for the thermal management of high-power electronic components.Besides,the IHSVC has been successfully applied to the thermal management of high-power LED.Due to the heat superior transfer performance of the vapor chamber integrated into the heat sink,the heat emitted by the LED dies can be transferred immediately and then dissipated into the environment.In addition,when compared with separate heat sink,the the heat dissipation performance of the IHSVC was improved because the integrated vapor chamber eliminated the contact thermal resistance.the The experimental results show that the high-power LEDs yields an favorable performance including the thermal and optical performance when the IHSVC unit was used.First,the performance of the wicks of IHSVC was studied.The interconnected micro-grooved wicks of the IHSVC was fabricated by micro-milling with a machining center using the proper taper tool.The permeability of the wick was studied using the forced flow method while the capillary rise height and rising rate were investigated using the IR-thermal imaging method.Furthermore,a comprehensive evaluation factor K·?P_capap was established based on the capillary limited heat flux in order to evaluated the theoretical capillary limited heat flux for the vapor chamber.The experiments indicted that the depth and pitch had effect on the wicks and the comprehensive evaluation of wicks was determined by both capillary pressure and permeability.Second,the IHSVC was manufacture and used to cool the LED.Systematic experiments are conducted to characterize the thermal and optical performances,and the IHSVC is compared with the conventional heat sink?CHS?under the same operating conditions.The temperature tests included junction temperature,thermal resistance and temperature uniformity while the luminous flux and the luminous efficacy were obtained in the luminous tests.The experimental results shown that the high-power LED yields a favorable performance using the IHSVC unit.At last,the simulation and experimental results are compared to testify the Icepak module.The results show that the simulation results were consistent with the experimental data.Therefor,this model could be reasonable for the thermal design of LED.