Solid-on-solid contact in a sphere-wall collision in a viscous fluid

Viscous dissipation in the collision between a sphere and a textured wall

“…The solid-on-solid contact occurs even just below the threshold of bouncing characterized by the critical Stokes number value St c 6. Birwa et al (2018) conclude that the mechanical contact between two colliding liquid-immersed objects is generic and will occur for any realistic surface roughness.…”

“…Collision with viscous dissipation 896 A8-15 The experimental collision times τ v reported by CGM close to the bouncing transition indeed varies between τ 0 and 1.6τ 0 . Note that Birwa et al (2018) also found an increase of the contact time for decreasing Stokes number close to their critical value St c 6: the contact time of a smooth steel sphere colliding onto a smooth steel wall into a viscous silicon oil measured from their electrical set-up was observed to be constant for 1.3 St/St c 5 and to increase abruptly very close to St c (1 St/St c 1.3), by a factor of 4 ± 2.…”

“…The influence of surface roughness on the sphere-wall hydrodynamic interaction was considered theoretically by Yang & Hunt (2008) and numerically by Ardekani & Rangel (2008), Simeonov & Calantoni (2012), Izard, Bonometti & Lacaze (2014) and Costa et al (2015). The question of the solid-on-solid contact in the sphere-wall collision in a viscous fluid was investigated recently by Birwa et al (2018) using an electrical experimental set-up: a voltage was applied between the plate and the sphere, and when the sphere makes or breaks electrical contact with the plate, the circuit closes or opens. Birwa et al (2018) have observed that the ball makes direct mechanical contact with the plate during the bounce, in contrast to expectations based on elastohydrodynamic theory.…”

“…The question of the solid-on-solid contact in the sphere-wall collision in a viscous fluid was investigated recently by Birwa et al (2018) using an electrical experimental set-up: a voltage was applied between the plate and the sphere, and when the sphere makes or breaks electrical contact with the plate, the circuit closes or opens. Birwa et al (2018) have observed that the ball makes direct mechanical contact with the plate during the bounce, in contrast to expectations based on elastohydrodynamic theory. The solid-on-solid contact occurs even just below the threshold of bouncing characterized by the critical Stokes number value St c 6.…”

On the collision of a rigid sphere with a deformable membrane in a viscous fluid

“…2015; Derksen 2015; Picano, Breugem & Brandt 2015; Biegert, Vowinckel & Meiburg 2017; Birwa et al. 2018; Yacoubi, Xu & Wang 2019). Conversely, when the bodies are deformable, the contact dynamics is more complex but the collision can still be described by simple models provided their shapes can be represented by a reduced set of parameters, as for small bubbles or droplets (Heitkams et al.…”