In this study, computational simulations have been performed to investigate the turbulent characteristics and energy consumption through heat exchanger tubes equipped by new perforated V-shaped rectangular winglet (PVRW) turbulators. The effects of the holes intensity on the velocity and temperature contours are additionally investigated. The Reynolds number, hole diameter ratio, and the number of holes are selected is in the range of 5000 ≤ ≤ 18000, 0 ≤ ≤ 0.40, and 0 ≤ ≤ 14, respectively. (RNG) k-ε turbulent model which is a finite volume solver is utilized for the CFD simulation. It was noticed that the proposed perforated turbulators could considerably intensify the thermal performance compared to typical VRW inserts. It is found that the recirculating flow generated by the PVRW, augments the fluid mixing and transfers the heat from the pipe walls to the core of the tube. The simulations illustrate that the amount of heat transfer enhances 25.2% with reducing the DR from 0.4 to 0.13 at Re=18000 and N=14. Also, using PVRW turbulators with N=7, DR=0.26 augments the average Nusselt number around 354.3% compared to the circular pipe without inserts. The highest thermal efficiency parameter of n=2.25 could be obtained at Re=5000 for the heat exchangers fitted by vortex generators with N=14 and DR=0.26.
|Journal||Journal of Energy Resources Technology, Transactions of the ASME|
|Early online date||12 Jun 2020|
|Publication status||Published - 1 Nov 2020|