Design and Development of an Experimental Apparatus for the Study of Heat Transfer and Friction Factor inside the Mini-Tubes with Different Inlet Configurations

Abstract

In this study, three types of inlet configurations (straight, 90o bend and 180o bend) were used in the heat transfer and friction factor experiments. The test section under the uniform wall heat flux boundary condition was a 2mm diameter stainless steel tube. The experimental range of Reynolds number is 1,000 to 10,000. There were 32 thermocouples set on top and bottom of the test section at x/D of 5 to 400. In the laminar region, 180o bend had a different heat transfer behavior in the developing region compared with others. However, in the transition region, different inlets have the similar heat transfer characteristics. The 180o bend has a higher turbulent heat transfer in the developed region. In the isothermal friction factor results, all the inlets are basically the same from the laminar to turbulent flow region.