基于场协同和火积耗散的截断型双层微通道热沉强化传热的数值模拟

Numerical simulation of enhanced heat transfer by heat sinking in truncated double-layer microchannels based on field synergy and entransy dissipation

摘要:

本文采用CFD技术数值模拟了波浪形双层微通道热沉的流动传热过程，分析了雷诺数和上层截断长度对流动和传热性能的影响。基于场协同原理与火积耗散理论，对比分析了四种双层微通道构型。结果计算表明，在层流状态下，随着雷诺数增加，微通道热沉的平均温度Tave逐渐降低，努塞尔数(Nu)；表面传热系数（h）和综合强化换热因子(PEC)提高，火积耗散逐渐减少。在相同雷诺数下，浪形底面上层通道长度比为0.2的双层微通道传热协同角和压降协同角最小。其中，具有浪形底面上层通道长度比0.2的Case1波浪形微通道热沉，在传热和流动特性上表现最优。

Abstract:

In this paper, the flow heat transfer process of wavy double-layer microchannel heat sink is numerically simulated by CFD technique, and the effects of Reynolds number and upper layer truncation length on the flow and heat transfer performance are analyzed.Based on the field synergy principle and entransy dissipation theory, four double-layer microchannel configurations are comparatively analyzed.The resultant calculations show that the average temperature Tave of the microchannel heat sink decreases gradually with increasing Reynolds number in laminar flow, and the Nussell number (Nu); surface heat transfer coefficient (h) and the integrated enhanced heat transfer factor (PEC) increase, entransy dissipation reduction.At the same Reynolds number, the two-layer microchannel with wave-shaped bottom upper layer channel length ratio of 0.2 has the smallest heat transfer synergistic angle and pressure drop synergistic angle. Among them, the Case1 wavy microchannel heat sink with a wave-shaped bottom upper layer channel length ratio of 0.2 performed optimally in heat transfer and flow characteristics.