Numerical Investigation on Heat Enhancement Method with Using Circular Dimpled Tube

Abstract

In this study, the effect of dimpled tube which is heated with constant heat flux on heat transfer enhancement is numerically investigated Using physically enhanced tube is one of the passive heat transfer enhancement methods. The reason of using dimpled tube is increase turbulence through the tube and destruct the thermal boundary layer. The numerical study is validated with an experimental study and configurations of cases are expanded with chancing pitch length. The considered cases are conducted in Reynolds number range of 3000 to 8000. Used fluid through the flow and its material copper are selected as water and copper, respectively. The k- ε RNG turbulence model is used to simulate turbulent flow adjacent the inner wall surface. The analyses are determined with Nusselt number (Nu), friction factor (f) and performance evaluation criteria (PEC). The highest Nusselt number and the minimum friction factor is obtained when the Reynolds number of 8000, as 135.54 and 0.0599, respectively, for pitch length of 10 mm and 50 mm. The highest THP value is observed as 2.01 by the case of pitch length of 10 mm and Reynolds number of 3000.