The heat fluxes from electronic components are steadily increasing and has now, in some applications, reached levels where air cooling is no longer sufficient. The increase of heat fluxes requires new methods of cooling of electronics. One efficient method of cooling is to use a closed loop two-phase thermosyphon system. In this project the thermal performance of a thermosyphon system for cooling of small electronic components has been investigated.
The setup utilizes three small evaporators connected in parallel, each made from a small block of copper in which five vertical channels with the diameter 1.5 mm and the length 15 mm were drilled. The paper presents the experimental results in terms of heat transfer coefficients of smooth surfaces as well as a threaded surfaces.
Tests were done at different heat fluxes while maintaining constant system pressure.
Test were performed with the heat loads 30-450 W dissipated through the system. Two different refrigerants, R134a and Isobutane were tested. The experimental two-phase flow heat transfer coefficients were compared to a correlation from the literature.