Direct Numerical Simulation of Moderate-Reynolds-Number Flows in Periodic Arrays of Spheres


Direct Numerical Simulation of Moderate-Reynolds-Number Flows in Periodic Arrays of Spheres

Tang, Y.; Kriebitzsch, S. H. L.; Peters, E. A. J. F.; van der Hoef, M. A.; Kuipers, J. A. M.

Simulations with an iterative immersed boundary method (IBM) are performed to obtain the drag force in the gas-solid flows at intermediate Reynolds number (Re). To validate the method, we first computed the steady flow around a single sphere at low Reynolds number (Re=0.1) and compared with the Stokes solution. Then, the flow was computed for Re=100, with the results compared with a reference solution by Zhang & Prosperetti (2005). Subsequently, numerous simulations were done for the flows past a face-centred-cubic (FCC) array at Re=100 with the solid volume fraction (ϕ) varying from 0.1 to close-packed limit. From the results obtained from various different diameter to grid size ratios, we extrapolate a resolution-free dimensionless drag force and formulate a fit of the drag as a function of ϕ. Furthermore, an effective diameter as a function of the resolution was determined from this fit and the simulation data. Finally we show for Re=100 and ϕ=[0.1,0.4], the reliable predictions of the mean drag in random arrays are obtained if one applies the effective diameter. Simulation results as presented in this work can be used to formulate an improved drag correlation, which is required by simulations at larger scales in a multi-scale modelling framework.

Keywords: direct numerical simulation; immersed boundary method; multi-scale modelling; drag force; spheres

  • Contribution to proceedings
    8th International Conference on Multiphase Flow 2013 (ICMF), 26.-31.05.2013, Jeju, Korea
  • Lecture (Conference)
    8th International Conference on Multiphase Flow 2013 (ICMF), 26.-31.05.2013, Jeju, Korea

Permalink: https://www.hzdr.de/publications/Publ-18261
Publ.-Id: 18261