Investigation Of Heat Pipe Applied On Cooling Of The Notebook PC

In the notebook PC,traditional single mode of air cooling doesn't satisfy the cooling requirement because of the limit of space and power.Heat pipe with excellent cooling capacity is applied on notebook PC. The principle of heat pipe and its working performance when applied on notebook PC are analyzed.The superiority of heat pipe on cooling over other cooling modes is analyzed.The heat transfer mode is built,and the corresponding quantitative calculation is made.The mechanism of heat transfer in heat pipe is analyzed.The thermal resistance and thermal performance are discussed and calculated with an example.According to the character of cooling to notebook PC, all kinds of limits to heat transfer are discussed, including stickness limit,sound limit,entrainment limit,capillary limit,condensation limit and boiling limit.The influence of the factors to the heat transfer is analyzed. The calculated results show that the capillary limit of heat transfer is much smaller than other limits of heat transfer. The relation between the limit of heat transfer and the dimension of heat pipe is discussed when the working liquid is confirmed. The dimension of heat pipe applied on cooling notebook PC is optimized in order to make heat pipe have better capacity on heat transfer,and the optimized length and diameter of heat pipe are obtained.The thermal performance of the heat pipe in notebook PC is analyzed numerically.The wall temperature, the thermal resistance and thermal performance are calculated when the power of the CPU and the dimensions of heat pipe are changed.The change of the limits of heat transfer is analyzed for different length,working temperature and obliquity of the heat pipe.