Design And Experimental Study On Flat Plate Loop Thermosyphon Radiator

Miniaturization and high performance have been the mainstream current of morden electronic equipment's development, which leads increasing rapidly of the heat power and heat flux. Thermal design of electronic equipment has been important more and more. Typically, such as CPU of computer, demands of which to performance and frequency is higher and higher. The heat power increases sharply, cooling problem stands out.A Flat Plate Loop Thermosyphon (FPLTS) radiator was proposed for desktop PC CPU and other electronic components cooling in this paper. The evaporator of FPLTS was maded out of a flat copper plate, a interspace inside it was excavated for working fluid, which evaporates in it. The condenser was made up of fin tube; and the working medium fluids by gravity.Heat sink radiator, heat pipe raditor, and FPLTS radiator models were set up Using ICEPAK tool, and their heat transfer performances were simulated numerically. Result shows: FPLTS radiator has distinct superiority in CPU temperature.FPLTS radiator was designed in detail and fabricated, and the method of choicing working fluid and filled ratio was explained. A wind tunnel performance testing systemwas set up. Based on the method of simulating electronic components with a heating copper block,, using water and acetone as working fluid, the porfermance of radiator under different heating power, different cooling wind temperature and different cooling wind speed were tested. The boiling heat transfer characteristics in evaporator and condensing heat transfer characteristics in condenser were studied experimentally and theoretically.Result shows: The boiling heat transfer coefficient and condensing heat transfer coefficient increase, the total thermal resistance of radiator decreases with the increasing of heating power. When heat flux is given, the total thermal resistance decreases with the increasing of cooling wind speed and wind temperature. The range of total thermal resistance is among 0.251~0.424℃/W, when wind speed is 3m/s, wind temperature is among: 25~40℃, heating power is among: 40~100W, with water as working fluid. The good heat transfer performance of radiator can address the demand of CPU and other electronic components with high heat flux.The theoretically results using boiling heat transfer formula and condensing heat transfer formula are in good greement with expermental results. These formula can be used for design of FPLTS radiators.