Heat Transfer Performance and Structural Optimization of a Novel Micro-channel Heat Sink

With the advent of the 5G era,the design of electronic equipment is developing towards thinness,intelligence and multi-function,which requires higher cooling performance of the equipment.Micro-channel heat sink is promising for the heat dissipation of super-thin electronic equipment.In this study,thermal resistance theoretical model of the micro-channel heat sink was first established.Then,fabrication process of the micro-channel heat sink was introduced.Subsequently,heat transfer performance of the fabricated micro-channel heat sink was tested through the developed testing platform.Results show that the developed micro-channel heat sink has more superior heat dissipation performance over conventional metal solid heat sink and it is well suited for high power LEDs application.Moreover,the micro-channel structures in the heat sink were optimized by orthogonal test.Based on the orthogonal optimization,heat dissipation performance of the micro-channel radiator was further improved.

Modeling and Simulation of a Hybrid Jet-Impingement/Micro-Channel Heat Sink

With the progressive increase in the number of transistors that can be accommodated on a single integrated circuit,new strategies are needed to extract heat from these devices in an efficient way.In this regard methods based on the combination of the so-called“jet impingement”and“micro-channel”approaches seem extremely promising for possible improvement and future applications in electronics as well as the aerospace and biomedical fields.In this paper,a hybrid heat sink based on these two technologies is analysed in the frame of an integrated model.Dedicated CFD simulation of the coupled flow/temperature fields and orthogonal tests are performed in order to optimize the overall design.The influence of different sets of structural parameters on the cooling performance is examined.It is shown that an optimal scheme exists for which favourable performance can be obtained in terms of hot spot temperature decrease and thermal uniformity improvement.

Heat Transfer of Heat Sinking Vest with Phase-change Material

To investigate thermal protection effects of heat sinking vest with phase-change material （PCM）, human thermoregulation model is introduced, and a thermal mathematical model of heat transfer with phase change has been developed with the enthalpy method. The uniform energy equation is constructed for the whole domain, and the equation is implicitly discreted by control volume and finite difference method. Then the enthalpy in each node is solved by using chasing method to calculate the tridiagonal equations, and the inner surface temperature of PCM could be obtained. According to the human thermoregulation model of heat sinking vest, the dynamic temperature distribution and sweat of the body are solved. Calculation results indicate that the change of core temperature matches the experimental result, and the sweat difference is small. This thermal mathematical model of heat transfer with phase change is credible and appropriate. Through comparing the dynamic temperature distribution and sweat of the body wearing heat sinking vest to results of the body not wearing this clothing, it is evident that wearing heat sinking vest can reduce the body heat load significantly.

Thermal Performance and Mechanics Characteristic for Double Layer Microchannel Heat Sink

Double layer micro-channel heat sink(DLMCHS) has been widely used in various electronic devices; however, the existence of the nonuniform thermal strain distribution in actual operation has adverse effect on the overall stability. In this paper, two optimized designs of DLMCHS with cutting baffles on top and bottom layers are presented based on the traditional DLMCHS. The heat transfer and thermal stress performance are numerically analyzed and compared with the traditional DLMCHS. The results indicate that cutting baffles of micro-channels remarkably improves heat transfer and thermal stress performance. The optimized design with cutting baffles on the bottom layer decreases thermal strain but deteriorates heat transfer performance. The model with cutting baffles on the top layer has better combined thermal strain and heat transfer performance, which reduces thermal strain by about 1.5 times and enhances heat transfer by about 26.5%. For the design with cutting baffles on the top board, adding metal foam in the inlet collector can decrease the total minimum thermal strain by 51.4% and maximum temperature by 1.4 K, and increase the Nusselt number by 15%. These results indicate that DLMCHS with cutting baffles on the top layer has great potential for thermal managements on electronic devices with high power density.