Impact of Temperature-Induced Buoyancy on the 2DOF-VIV of a Heated/Cooled Cylinder

This study examines the effect of different wall temperatures on the vortex-induced vibration (VIV) of a circular cylinder under thermal buoyancy. It addresses a notable research gap by examining how changes in the Richardson number influence VIV, particularly in the context of two-degrees-of-freedom VIV, and mixed convection heat transfer. Numerical analysis is used, combining Euler’s integration approach with a finite volume solver. Validation against mixed convection heat transfer data is carried out for both stationary and sprung cylinders with one-degree-of-freedom VIV. The findings show that increasing the Richardson number for a heated cylinder slows vortex shedding, leading to the establishment of a stable vortex pair and a decrease in Nusselt number oscillation. Within the lock-in zone (4 ≤ U_r ≤ 7), the heat transfer rate decreases by 12.3% at U_r = 5 as the Richardson number climbs from 0 to 1. Conversely, lowering the Richardson number for a cooled cylinder increases vortex shedding, resulting in increased vibrations and Nusselt number amplitude. Even at U_r = 9, VIV stays in the lock-in area when Ri = − 1.