Experimental investigation of laminar forced convection flow of nano fluid in helical pipe

Helical coils and nanofluids are among efficient methods for heat transfer augmentation. In the present study, a heat exchanger was designed, capable of providing constant wall heat flux for coils with different curvature and torsion ratio for the ease of assembly. Laminar flow in helically coiled tubes under constant wall heat flux is experimentally investigated. Pressure drop and convective heat transfer behavior of water and water– Titanium oxide nano fluid, with three different volume fraction, are studied. The pressure drop measurements as well as the average convective heat transfer coefficient calculations are carried out. Finally, using theexperimental results, the averaged Nusselt number is calculated. It was found that the utilization of the base fluid in helical pipe with greater curvature ratio compared to the use of pure water in helical coil increased heat transfer more effectively. experimentalresults show an 8% increase in the heat transfer for different tube geometries and different Re numbers.

کلیدواژه ها:

Nanofluid ، Helical coil ، Laminar forced convection ، Constant wall heat flux