Role of the Particle-Fluid-Particle Pressure Tensor in Gas-Liquid and Liquid-Solid Flows
Particle-particle interactions play a crucial role in the fluid dynamics of gas-liquid and liquid-solid systems. In such systems, the fluid density is comparable to, or larger than, the particle density and fluid-mediated particle-particle interactions lead to non-negligible stresses in the particle equation of motion, i.e., the particle-fluid-particle (PFP) pressure. Such effects are observed in particle-resolved direct-numerical simulations of particle sedimentation to influence particle-velocity fluctuation statistics and the wavelength of kinematic waves.
Standard Eulerian-Lagrangian (EL) models for inertial particles do not resolve neighbor-induced fluid-velocity fluctuations (pseudoturbulence) and partially resolve coupling with particle-velocity fluctuations. By implementing a closure for the PFP pressure in an Eulerian-Lagrangian (EL) framework, our simulation results illustrate the effect of the PFP pressure on the particle-velocity fluctuations and kinematic waves in liquid-solid sedimentation. Since the PFP pressure scales with the liquid density, even stronger effects are observed in bubbly flows..
Contact Martin Obligado for more information or to schedule a discussion with the seminar speaker.