Heat transfer in Minichannels and Microchannels CPU cooling systems

摘要

A CPU functioning is extremely complex and it was experimentally revealed that a direct dependence between working speed and cooling degree exists. When the contact between two surfaces is imperfect, the specific thermal resistance of interface layer suddenly increases, so it became of frequent use to apply diverse materials between the CPU and radiator. These materials should both fill the gaps occurred due to surfaces roughness, material's fatigue, loading pressure etc. and transfer as much heat as possible during a short period of time. In order to ensure an appropriate cooling, other complementary methods are used, such as coolers, water or other liquids cooling, Peltier effect and even freon micro-refrigerating systems. In either situation, there are micro or nano channels through which fluids flow and thermal exchange takes place. The present paper aims to analyze the heat transfer under the mentioned conditions, considering the micro or nano scale dimensions of the channels. The thermal calculus can differ with respect to Kn number and for this case for thermal modelling diverse mathematical models can be realized. The model used is validated by comparing the results to numerical results obtained by authors from literature.