On the drag coefficient and averaged Nusselt number of an ellipsoidal particle in a fluid

The paper aims to improve existing correlations for the drag coefficient and averaged Nusselt number of an ellipsoidal particle in a fluid by additionally considering its orientation. To do so, three-dimensional Immersed Boundary-Lattice Boltzmman Method (IB-LBM) simulations were carried out on a classical problem where a hot stationary ellipsoidal particle was passed by continuous cold fluid flows. By changing the shape (0.25 ≤ Ar≤ 2.5) and incident angle (0°≤ θ≤ 90°) of the solid particle as well as the Reynolds number (10 ≤ Re≤ 200), the momentum and heat transfer between the solid and fluid phases were quantitatively evaluated and the drag coefficient and averaged Nusselt number were numerically quantified. Then, based on the obtained data, correlations for the drag coefficient and averaged Nusselt number were established by considering Ar, θ and Re as the key influencing factors. Proposed correlations were proven to hold promising prediction capabilities and would be useful to be enclosed in those complex multiphase coupling calculations.