We study through direct numerical simulations the water entry of yield-stress droplets. Following the impact on water free surfaces, these Non-Newtonian fluids undergo at least three stages: a spreading one (1), related to the impact acceleration, driven by the viscous dissipation and during which the droplet reaches its maximum deformation; a droplet-water interaction stage (2) along which the viscoplastic material tends to recover its initial morphology before being finally dominated by the yield-stress (3), which prevents further deformations. Different final shapes are observed as a function of the capillary, viscous and inertial effects. Their link with the fluid rheology is discussed in the light of scaling laws, kinematic and energy exchange analyses.
| Type : | : | poster |
| Thématiques | : | S10 - Écoulements multiphasiques, écoulements aux interfaces |
| Mots-Clés | : | water entry ; yield ; stress fluid ; direct numerical simulation |
| PDF version | : |  PDF version |
