并联微通道热沉 R134a 沸腾换热动态响应实验研究

This paper conducts an in-depth study on the dynamic characteristics of boiling heat transfer of multiple microchannels heat sinks under multi-heat source scenarios. Using R134a as the working fluid, the multiple microchannels heat sink system under different mass fluxes was tested. The heat sink contains 41 microchannels with a hydraulic diameter of 0.55 mm. The steady-state and transient characteristics of boiling heat transfer of the multiple microchannels heat sinks were explored and compared with the single microchannel heat sink. The results show that the boiling heat transfer coefficient curve of the multiple microchannels heat sink is similar to that of the single microchannel heat sink. Due to the differentiated heat input, the flow rate and pressure drop in the multiple microchannels vary dynamically, resulting in a decrease in the maximum heat flux of the multiple microchannels by up to 30%, and a flow non-uniformity of up to 63%. The greater the power density, the greater the degree of flow non-uniformity. The research results have important reference significance for the efficient and stable operation of multi-heat source electronic devices.