微小通道流动换热特性分析及其结构优化

就一组不同水力直径的矩形微小直通道进行了实验研究,并通过经验证的数值方法进行了大量CFD计算,得到了通道内流体努塞尔数和阻力系数随雷诺数变化的规律.结果表明,在所研究微小尺度范围内通道内流动的转捩雷诺数提前到1 200～1300之间,以大量数值模拟结果为样本点经过多元线形回归建立了所研究范围内微小通道流体换热与流动特性的准则关系式,并基于遗传算法,对矩形微小通道的几何结构进行了优化,为工程应用提供了依据. 

Investigation on flow and heat transfer characteristics and optimum structural design in the rectangular microchannels

For obtaining the basic characteristic of flow and heat transfer in the rectangular microchannels,experiment was executed under different hydraulic diameters,and a great deal of numeration simulations were carried out and validated experimentally.The transformation laws of Nusselt number and resistant coeffcient were obtained.The critical Reynolds number was brought forward to about 1 200～1 300 in the studied scale range.Meanwhile,the correlation of Nusselt number and resistant coeffcient within the studied scale range were built by multivariate linear regression.The optimization procedure(genetic algorithms) was carried out to optimize the structure of microchannels,providing beneficial theoretical and experiment data for engineering application.