微型硅基内肋管内的流动与换热特性

目前内肋管强化换热研究大多基于铜、铝或者不锈钢等常规材质，其加工精度和加工尺寸均受到限制。本文采用MEMS工艺首次在硅片上制作成带有方形内肋的平行硅基微通道，并对其内部流动和换热特性进行了实验研究，结果表明：在通道深度和宽度相同的情况下，肋高和肋间距对工质在通道内的流动阻力和换热特性有显著的影响;微通道内加肋以后，通道内的流动阻力和换热性能有不同程度的增加，且提高程度与肋高和肋间距有关;通过合理的设计肋高和肋间距，可以起到明显的强化换热作用。结果还显示，进口段效应对硅基微通道内的流动和换热影响较为显著。

Flow and heat transfer characteristics in silicon-based microchannels with internal ribs

At present, channels made of copper, aluminum or stainless steel are widely used for the heat transfer enhancement research, but the fabrication precision and size of these traditional channels are usually limited.In this paper, silicon-based microchannels with square internal ribs were made by the MEMS method, and their flow and heat transfer characteristics were experimentally investigated for the first time.It was shown that the flow and heat transfer characteristics were affected apparently by rib height and the distance between two neighboring ribs.When compared with the smooth silicon microchannels without internal ribs, both the friction factors and Nusselt numbers of the silicon microchannels with internal ribs increased, and the heat transfer enhancement performance of the silicon-based microchannels with internal ribs was mainly dependant on rib height and rib distance.The entrance effect on the flow and heat transfer in the silicon microchannels was obvious.