ABSTRAKT

Today, combining heat pipe and nanoparticle technologies is reported to enhance the efficiency of heat transfer devices. Suspensions of nanoparticles and fluids, called nanofluids, have a great impact in heat transfer enhancement. This paper presents an experimental investigation regarding the effects of organic nanofluids on the efficiency of a two-phase closed thermosyphon. The experimental results showed that, for different input powers, in some cases (ethanol/CuO) the efficiency of the thermosyphon improved compared to the case of using pure base fluid. For instance, acetone/Fe₂O₃ and ethanol/CuO nanofluids with 0.5-2% weight fraction of nanoparticles as the working fluids present better thermal performance over a wide range of input power. However, the improvements were small and for ethanol/Fe₂O₃, nanoparticles had the reverse effect. The maximum improvement in efficiency was about 13% in some input powers. In addition, temperature distributions on the thermosyphon confirmed these results too.