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With the rapid development of electronic technology, higher calculation speed and frequency, and denseness and miniaturization of the integrate circuit has become the developmental direction of the electronic component, which result in the rapidly increasing of the heat flux of electronic component per unit volume in recent years. The excellent measure of heat transfer is needed to adapt to the development of electronic technology. The miniature flat heat pipe, as a heat transfer device which utilizes the phase change of working liquid in it, have been applied in electronic engineering because of its essential characteristics of compact structure, high heat thermal conductivity, excellent isothermal property, the variability of the heat flux density, the reversibility of the heat flux direction, the characteristic of constant temperature, the adaptability of the environment and so on. In this thesis, a new style miniature flat plate heat pipe of electronics cooling was designed and manufactured, and the theoretical analysis and experimental research on it was conducted.Based on the Cotter heat pipe theory, the theoretical analyses were researched. The mechanism of heat transfer of axial channel flat plan heat pipe was analyzed, and the heat transfer limitations of heat pipe under different working temperatures were calculated.Firstly, according to the work conditions, the heat pipe was designed, which included the selection of the working fluid and the heat pipe shell material, the design of the shell and the triangle flat structure, the calculation of the quantity of the working fluid. Water and acetone as the working fluid, and the stainless steel as the material of the shell and the triangle flat was selected to manufactured the heat pipe. And its manufacturing process was studied, which consisted of mechanical machining, cleaning, assembly and welding, checking for leakage, charging.Then, the experimental test scheme was confirmed. And based on it, the experimental table was set up to research the heat transfer performance of the heat pipe. The effects of heat power, filling ratio, inclination and working fluid on the heat transfer performance were analyzed. The results are as follows:(1) The optimum filling ratio is about 25%;(2) The gravity plays a assistant role in improving the heat transfer performance of the heat pipe;(3) Water as the working fluid is better than acetone to display the heat transfer performance;(4) The best heating power in different working fluids and different filling ratio is between 60W and 90W.And results indicate that the new style miniature flat heat pipe have the nicer heat transfer performance.Last, a new method of evaluating the heat transfer performance of heat pipe, which is called a method of coefficient of equivalent convention heat transfer, is described. And use it to analyze the experiment. Its conclusion is the same to the traditional method, which attested that the method of coefficient of equivalent convention heat transfer is also suit for evaluating the heat transfer performance of heat pipe.
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