Experimental Study of Thermal Performance of a Newly Designed Pulsating Heat Pipe with Fe3O4 Nanofluid-Exposed Magnetic Field and Corrugated Evaporator

Use of oscillating heat pipes as a new component related to heat transfer has always been of interest for different technologies in recent years. A novel U-shaped structure is designed for the 3D-PHPs and this novel design creates a high performance device. In this experimental study, the thermal performance of a newly designed three-dimensional pulsating heat pipe with Fe3O4 nanofluid exposed to magnetic field under different heat inputs (0 W to 450 W). The results showed that the filling ratio of 50 % had better thermal performance. Our results indicated that the use of iron oxide nanofluid (Fe3O4) at 2 % mass concentration significantly improves the thermal performance of the pulsating heat pipe especially in 50 % filling ratio compared to pure water, which also showed that the improvement of heat transfer coefficient can be better by using corrugated evaporator under magnetic field. The results show that when the evaporator of 3D-PHP is exposed to a constant magnetic field, the thermal performance of the device improves significantly. The results showed that thermal resistance has been reduced 18 %, 20 %, and 25 %, respectively, for nanofluid with 50 % filling ratio and corrugated evaporator and under magnetic field compared to water. Compared to pure water operating fluid, application of nanofluid, magnetic field, and corrugated evaporator reduces the average heat resistance and increases the heat transfer coefficient. This investigation will promote the development of effective cooling for electronic devices.