Design And Performance Study Of Flat Heat Pipe Working For Electronic Equipment

With the development of electronic equipment, the heat dissipation of electronic devices has become the bottleneck of restricting its development; the traditional cooling methods cannot meet the increasingly stringent cooling requirements. And the flat heat pipe becomes one of the most promising technologies to solve the heat dissipation of the electronic equipment for its high heat transfer performance and good thermal homogeneity. The flat heat pipe uses phase-change heat transfer and has great superiority than other heat exchange way, and because of its good thermal homogeneity it can be used to strict temperature variations of high-grade equipment. So the study of flat heat pipe radiator is of great significance. In this paper, the theoretical and experimental research was conducted on the flat heat pipe thermal spreader; the main work is as follows:First understand the workings of a flat heat pipe through the literature and the radiating advantages, understand on a flat plate heat pipe research status at domestic and overseas. To make the technical scheme, and then determined by preliminary experimental flat heat pipe choose gauze as absorbing liquid core material, determine the experiment system. After building experiment platform, the production of flat heat pipe was carried out. After that, we begin to experiment, the experimental parameters including liquid-filled ratio were 0%, 20%, 40%, 60%, 80%; heating power 24 W,32 W, 40 W, 48 W, 56 W, 64 W. The experiment studies after start-up characteristics of flat heat pipe, measuring the surface temperature distribution of the flat heat pipe working against anti-gravity and the temperature of simulated heat source, then study the temperature distribution and its influence on the performance of the flat heat pipe.After analysis of the temperature distribution of flat heat pipe we can know that power and filling rate have important influence on the temperature distribution. The temperature without liquid increase is proportional to the increase in power, the liquid increases with the increase of power after temperature gradually slow. The study found that when the liquid-filled ratio were 20% flat heat pipe thermal homogeneity are the best performance, but under the same power the liquid-filled ratio has a different influence on the upper and lower surface of the flat heat pipe, as the change of liquid-filled ratio the upper surface temperature change is bigger, and the lower surface temperature change is small, this is because the upper surface comparing to the lower surface is easier to obtain working medium. Through analyzing of the heat source temperature, the simulate heat source temperature is lower than other liquid rate at the highest liquid-filled ratio of 80%, the charging rate is bigger, the heat dissipation of the heat source is better. Through analyzing of thermal resistance of flat heat pipe, with increase gradually of power thermal resistance gradually dropped to 0.092 K/W from 0.371 K/W, that is the heat pipe heat dissipation performance in increasing with the increase of power; After compare of the thermal resistance at different liquid-filled ratio, the average thermal resistance obtains the minimum of 0.182 K/W at the liquid-filled ratio of 20%.Through experimental study, it is obviously that the flat heat pipe gets the best performance of thermal homogeneity at the liquid-filled ratio of 20%., the maximum temperature difference is 16.6℃ in maximum power 64 w, the highest temperature under 80 ℃, its cooling effect is better than the maximum temperature difference at 29.9℃ of empty radiator, provide the basis for the flat heat pipe radiator used in electronic components.