The entropy generation for a rotating sphere under uniform heat flux boundary condition in forced-convection flow

Purpose - The purpose of this paper is to investigate the problem of entropy generation around a spinning/non-spinning solid sphere subjected to uniform heat flux boundary condition in the forcedconvection regime. Design/methodology/approach - The governing continuity, momentum, energy and entropy generation equations are numerically solved for a wide range of the controlling parameters; Reynolds number and the dimensionless spin number. Findings - The dimensionless overall total entropy generation increases with the dimensionless spin number. The effect of increasing the spin number on the fluid-friction component of entropy generation is more significant compared to its effect on heat transfer entropy generation. Research limitations/ implications - Since the boundary-layer analysis is used, the flow is presented up to only the point of external flow separation. Practical implications - Entropy generation analysis can be used to evaluate the design of many heat transfer systems and suggest design improvements. Originality/value - A review in the open literature indicated that no study is available for the entropy generation in the unconfined flow case about a spinning sphere.