Modelling and Analysis of Fluid-Particle Interactions

Abstract The particle-fluid interaction of non-reactive ellipsoidal particles is studied in turbulent particle-laden flows. Highly resolved direct particle-fluid simulations, capturing all turbulent scales, provide necessary reference solutions for the development of Lagrangian point-particle models. Studies in decaying isotropic turbulence highlight the effect of particle shape on turbulence modulation and reveal the limits of existing point-particle models for non-spherical particles, unable to accurately predict the dynamics of Kolmogorov-length scale sized ellipsoidal particles. To address this, correlations that account for finite particle Reynolds numbers, particle shape, and orientation have been developed for drag, lift, torque, and heat transfer. Simulations of isotropic and anisotropic turbulent flows reveal that conventional spherical and ellipsoidal point-particle models without the novel correlations tend to overestimate the particle velocity. In addition, the non-spherical particles tend to align their major axes along the flow direction if finite particle Reynolds number effects are not considered by the model. In contrast, applying the new correlations results in a preferred orientation perpendicular to the flow direction.