Fluid flow lifting a body from a solid surface.

If a body is at rest on horizontal ground and a sudden horizontal flow of fluid is applied, the body either remains on the ground (rocking, rolling, sliding or spinning) or is lifted off impulsively. This lift-off is followed by a return to the ground or by a fly-away in the sense of continued departure from the ground. Related phenomena arise in the lift-off of an air vehicle from, effectively, moving ground.

Movement of a finite body in channel flow.

A body of finite size is moving freely inside, and interacting with, a channel flow. The description of this unsteady interaction for a comparatively dense thin body moving slowly relative to flow at medium-to-high Reynolds number shows that an inviscid core problem with vorticity determines much, but not all, of the dominant response. It is found that the lift induced on a body of length comparable to the channel width leads to differences in flow direction upstream and downstream on the body scale which are smoothed out axially over a longer viscous length scale; the latter directly affects the change in flow directions.

Collisions, rebounds and skimming.

Repeated oblique impacts and rebounds of a solid body or bodies on horizontal shallow water are investigated through mathematical modelling. The inclinations from the horizontal are supposed small as the skimming evolves, for a thin typical body shape. The new formulation aimed at improved prediction as well as the background involved is presented together with nonlinear analysis and computation.

Fluid-body interactions: clashing, skimming, bouncing.

Solid-solid and solid-fluid impacts and bouncing are the concern here. A theoretical study is presented on fluid-body interaction in which the motion of the body and the fluid influence each other nonlinearly. There could also be many bodies involved.

Vortices and flow reversal due to suction slots.

Suction into small two- or three-dimensional surface slots inside an otherwise planar boundary-layer is examined theoretically through a combined analytical and computational approach. Increasing suction strength leads to enhanced nonlinear structures with flow reversals or trailing vortices.