周期性变截面微通道结构参数对流体流动和传热的影响

Influence of structural parameters on fluid flow and heat transfer in microchannel with periodically changeable cross-sections

周期性变截面微通道扇形凹穴的设计,使通道内流体流动分为等直径流速型和弧形流速型,因此微通道的等直径段和弧形段的长宽度等结构参数对流体流动和传热有重要影响。针对周期性变截面微通道单相液体流动与传热特性,利用计算流体力学(CFD)模拟与分析软件进行了三维数值模拟。模型采用有限体积法离散、SIMPLEX算法进行层流计算。分析结果显示,等直径段和弧形段的长宽度等结构参数对周期性变截面微通道流体流动特性和传热特性有重要影响。在本文的模拟条件下,u=4m.s-1时,其最佳结构参数范围为0.15<L1/L2<2,1.4<W2/W1<2.1。

Due to the design of fan-shaped reentrant cavities, the microchannel with periodically changeable cross-sections is divided into constant diameter region and arcuate region. The structural parameters, including the lengths and widths of the constant diameter region and the arcuate region have an important influence on the behavior of fluid flow and heat transfer in the microchannel with periodically changeable cross-sections. The influence of structural parameters with three-dimensional numerical analysis was investigated in this paper. The steady, laminar flow and heat transfer equations were solved by using a finite-volume method. The analysis showed that the influence of different structural parameters on fluid flow and heat transfer was very significant. When u=4 m.s^-1, the optimized structural parameters were 0.15〈L1/L2〈2,1.4〈W2/W1〈2.1.