ENHANCING HEAT TRANSFER AND SUPPRESSING FLOW-INDUCED VIBRATIONS THROUGH CYLINDER ARRANGEMENT MODIFICATION

This study delves into the influence of cylinder arrangements on flow-induced vibrations and heat transfer within the laminar regime, specifically at a Reynolds number of 100. The investigation involves the oscillatory behavior of two cylinders, each permitted motion in two degrees of freedom: parallel to the flow direction (streamwise) and perpendicular to it (transverse). The configuration of two identical circular cylinders varies from tandem alignment (α = 0°) to staggered (α = 15°), with a fixed spacing of 6D between them, where D represents the cylinder diameter. Maintaining a constant temperature, the cylinders were subjected to heat transfer analysis to determine the impact of two-dimensional flow-induced vibrations (FIV). The outcomes emphasized the sensitivity of cylinder response to variations in reduced velocity and cylinder configuration, particularly concerning FIV and heat transfer phenomena. Notably, tandem alignment exhibited the most pronounced vibrational responses in both cylinders. Placing the cylinders in staggered arrangement resulted in lower vibrational responses accompanied by a diminished lock-in zone which is characterized by significant transverse vibration amplitudes. However, the staggered arrangement led to higher Strouhal numbers, indicative of increased vortex shedding frequencies. While streamwise vibrations were negligible in the tandem setup, they were prominent in the staggered arrangement. Importantly, the staggered setup demonstrated a notable 23% reduction in transverse vibrations and an 36% increase in the averaged Nusselt number for the downstream cylinder compared to the tandem configuration. These findings suggest the superiority of staggered cylinder setup over tandem alignment for enhancing heat transfer and mitigating FIV effects.