The effect of slip on the development of flow separation due to a bump in a channel

• DOI: 10.1017/jfm.2022.863
• Publication Date: 2022-11-08T11:25:26Z
• Authors: Silvia Ceccacci; Sophie A.W. Calab...; Christian Thomas; James P. Denier
• Keywords: Slip ratio; Separation (statistics)

A numerical study on the effect of surface slip flow in a constricted channel is presented, with aim exploring use to control separation. Our focus two-dimensional over bump, fixed aspect ratio, upon which Robin-type boundary condition imposed. When walls are fully no-slip, such known develop region separation behind at sufficiently large Reynolds numbers. The bubble dynamics occurring bump investigated, for numbers $2000$ and $4000$ . It shown that (i) attenuates intensity as it diminishes minimum streamwise velocity within recirculation region; (ii) delays onset separation, shifting downstream, along (iii) reduces dimensions allowing reattach sooner. Ultimately, inhibits both points reattachment coalescing, length $\lambda$ approximately $0.2$