Ali Akbari - M.Sc. Student, School of Mechanical Engineering, Sharif University of Technology;
Mohammad Hassan Saidi - Professor, School of Mechanical Engineering, Sharif University of Technology;

Pulsating heat pipe (PHP) is a kind of wickless heat pipe that has a simple structure and outstanding thermal performance. Nanofluid is a fluid that contains nanoparticles dispersed in base fluid and has a better thermal conductivity in comparison to its base fluid. In this article the performance of nanofluid PHP has been investigated. Graphene/DI water nanofluid with concentration of 1mg/mlit and TiO2/DI water nanofluid with concentration of 10 mg/mlit were used as working fluids. In order to investigate the thermal performance and flow regimes in PHP Simultaneously, a one turn copper PHP with a Pyrex glass attached to its adiabatic section was used. A one turn Pyrex PHP also is used to fully visualize the flow patterns in the PHP. Our results showed that the thermal performance of PHP using stable nanofluid is better than water and, on the other hand, unstable nanofluid can deteriorate the thermal perormance. In case of flow regimes no significant differences were observed between nanofluid PHP andwater PHP. These results can help researchers to choose the best working fluid for PHP.

pulsating heat pipe, titania/water nanofluid, graphene/water nanofluid, flow patterns/regime thermal performance