Loop thermosyphon has many good characteristics such as low thermal resistance, no power consuming, noiseless operating condition and small size. To investigate the overall performance of loop thermosyphon, we have performed various experiments varying three parameters: input power of the heater, working fluid(water, ethanol, FC3283) and filling ratio of the working fluid. At a combination of these parameters, temperature measurements are made at many locations of the loop thermosyphon. The temperature difference between the evaporator and the condenser is used to obtain the thermal resistance. In addition, flow visualization using a high speed camera is carried out.
The thermal resistance is not constant. It is lower at higher input power. Flow instabilities are frequently observed when changing the working fluid, the input power and the filling ratio.
The results show that the loop thermosyphon can be readily put to practical use. Future practical application in electronic cooling is recommended.