On the wake structure behind a heated horizontal cylinder in cross-flow

摘要

This paper describes a numerical and experimental study of the effect of heat input on the behaviour of the vortices shed from a horizontal cylinder in a horizontal cross-flow. The Reynolds number (Re-D) is fixed at 75, while the Richardson number (Ri(D)) is varied between 0 and 1 (corresponding to forced and mixed convection, respectively). In this parameter regime the wake consists of a double row of alternately shed vortices. A rather unexpected effect of the induced heat is the downward motion of the shed vortex structures. Detailed experiments and numerical simulations show that this effect is caused by, the difference in strength between the two vortex rows. An analysis of the vorticity sources present during the formation process shows that the thermally induced baroclinic vorticity production is mainly responsible for this. [References: 22]