Periodic flow pattern and convection heat transfer in an arc-shaped cavity with oscillating lid

The present study is concerned with periodic behavior of mixed-convective flow in an arc-shaped cavity with a vibrating lid. Numerical predictions of the effects of frequency of the vibration of the lid on the cavity flow and heat transfer are presented. In this study, the dimensionless frequency of the lid velocity ranges between 0 and 1.0 in order to investigate the lid vibration effects extensively. The interaction between the frequency of vibration of lid velocity and the frequency of the natural periodic flow is of major concerns. Results show that the frequency of vibration of lid velocity and the natural periodic flow frequency both appear to be major frequencies in the frequency spectrum of the cavity flow, for cases with dimensionless lid vibration frequency less than 0.4. When the dimensionless frequency of vibration of lid velocity is equal to or greater than 0.4, the flow and thermal fields are completely "locked on'' by the lid vibration, and the natural periodic flow frequency is no longer visible in the spectrum. In this study, predictions of the local and average Nusselt numbers on the walls as well as the transient flow patterns corresponding to various combinations of the physical parameters are also presented.