Two-phase flow analysis of a double layer counter flow mini-channel heatsink with 1D countercurrent flow model

Abstract

The mini and micro-channel heat sinks with two-phase flow boiling are considered as one of the promising cooling methods because they can effectively manage the high heat flux heat dissipation. However, it is characterized by a significant decrease in the heat transfer coefficient of the liquid deficient portion where the quality of flow is increased by the boiling in the channel. In particular, the heat transfer coefficient at which the wall dry-out occurs sharply decreases, which can cause a large temperature gradient in the direction of flow. Such a dry-out condition may correspond to the critical heat flux state, and a drastic decrease in cooling performance is inevitable. In order to alleviate the temperature gradient increase and to improve the cooling performance, the two-phase counter flow micro-channel heat sink with double layer structure has been proposed. The proposed microchannel heat sink was numerically analyzed by applying 1d two-phase flow in each counter flow direction. Two-phase boiling heat transfer correlation and momentum equation were solved to calculate the pressure drop and analyze the cooling performance benefits of proposed counter flow heat sink. From the results of the analysis, it was confirmed that the counter flow heat sink can obtain a more uniform temperature distribution than the conventional unidirectional heat sink.