Numerical prediction of lock-on effect on convective heat transfer from a transversely oscillating circular cylinder

Heat transfer characteristics and the flow behavior of cross flow over a transversely oscillating cylinder are investigated. The lock-on phenomenon has been predicted numerically and its influence on the heat transfer performance of the cylinder is evaluated. The SOLA method is employed to solve the unsteady velocity field in a non-inertial reference frame, and the energy equation is solved by a finite-volume method. Transient variations of the Nusselt number and the drag and lift coefficients are calculated for various oscillation conditions. The ranges of the dominant parameters considered in this study are 0 ≤ Re ≤ 300, 0 ≤ S_c ≤ 0.3 and 0 ≤ A/D ≤ 0.7. The Prandtl number is considered to be 0.71 or 7.0. In the lock-on regime, an appreciable heat transfer increase caused by the oscillation is observed ; however, outside this regime, the heat transfer is almost unaffected by the oscillation. A correlation formula expressing the dependence of heat transfer on these dominant parameters in this lock-on regime is presented. The numerical predictions have been compared with the existing information, and good agreement has been found.