Abstract
In micro-channel flow with backward step, the effects of the flow and heat transfer with the mixture of multi-size particles are investigated experimentally for the control of the flow and heat transfer field. In the area of micro-size, it is not easy to control the heat transfer with increasing and decreasing locally by devices and external forces but it is possible to perform using non-direct phenomena with the mixture of multi-size fluorescent particles in the flow. Because of the velocity distribution, the tracking line of multi-size particles may be different from the drag effects of the each body size. Then, the velocity distribution would be changed more emphasized by big-sized particles and passing by mid-sized particles. It would be needed three kind of particle size at least to perform and detect the phenomena. From the results, several qualitative interesting effects were given with the continuous pictures and immature image analysis, and the quantitative results would be got and reported after the building and confirming the newer image processing methods.