Effects of wavy ribs on vortex generation and thermal-hydraulic performance in a rotating rectangular channel
Tofigh Moradi, Hamidreza Shahbazian, Mostafa Hoseinalipour, Bengt Sundén
Abstract
An experimental and numerical study has been conducted to analyze the effects of rib configurations on heat transfer in U-turn rotating rectangular channels with smooth walls. A new model of a wavy rib is studied and compared with traditional ribs in a rectangular cross-section. Heat transfer coefficients for all rib configurations were measured from Reynolds numbers 4000 to 12000, whereas rotation numbers ranged from 0.025 to 0.15. Computational fluid dynamics (CFD) with the k-ω SST turbulence model were utilized to investigate turbulent kinetic energies, Nusselt numbers, flow structure, and thermal performance. The results indicated that the thermal performance factor of wavy ribs was 22.1%–28.7% higher than the rectangular cross-section ribs. The effects of Coriolis and rotational buoyancy result in growth and reduction of heat transfer in the leading and trailing walls. The simulation results are supported by experimental data with a difference of 3 to 10% for all samples, respectively.