Ali Amiri - Ph.D Student , Micro and Nano Mechanical Theory , Department of Mechanical Engineering , Tsinghua University , ۱۰۰۰۸۴ Beijing , China

The purpose of this project is to evaluate the convection heat transfer and the specifications of the viscous pressure drop of alumina-water nano-fluid. Nano-fluids are based on the colloid emission of nanoparticles in metal, metal oxide, carbon materials in fluids, and nano-fluids have a better heat transfer than base fluids. The flow loop was designed with a vertical thermal section and was developed to operate in a laminar flow process at the Reynolds higher than 2000. Initial tests were performed to confirm the test by deionized water. Alumina nano-fluid was tested in a flow loop by four volumetric loading of 0.6, 1, 3 and 6%. If dependent thermo-physical characteristics on loading and temperature are used, then the experimental results presented in the Nusselt number and the dimensionless length of x+ will in agreement with the predictions of traditional model. The measured pressure drop of nano-fluid is at the 20% of theory. It is concluded that the laminar convection heat transfer and the viscous pressure drop behavior of alumina-water nano-fluid can be predicted using existing models, until the ideal mixture characteristics are used, and there is no abnormal increase in heat transfer.

Pressure drop, Convection heat, Nan-fluid viscose, Alumina-water