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DNS study of local-equilibrium models in dilute particle-laden turbulent pipe flows

  • A. M. P. Boelens
  • L. M. Portela
Conference paper
Part of the ERCOFTAC Series book series (ERCO, volume 11)

Abstract

A two-fluid closure model, commonly used in engineering simulations, is the drift-velocity model of Simonin. In this work, this model is evaluated for dilute particle-laden pipe flows, using Direct Numerical Simulations (DNS) with particle tracking. The simulations were performed with both heavy and light particles (particle relaxation-times of τ 2 + = 100 and τ 2 + = 10, respectively) and with reflecting and absorbing walls as the boundary conditions for the particles, resulting in four different cases. For all the cases, except the combination of heavy particles and absorbing walls, from a pragmatic point of view, the assumptions of local-equilibrium and homogeneous turbulence seem to hold. For the drift-velocity two models were evaluated: (i) a simple Schmidt-number model, and (ii) a more advanced drift-tensor model. From an engineering perspective, for light particles with reflecting walls the Schmidt-number model appears to be the best choice. However, when the particles are heavier or when the walls are absorbing, the more advanced drift-tensor model gives better results. For these cases, provided that there exists good closure models for the time-scales and particle-fluid velocity correlations, a drift-tensor model could be a better option.

Keywords

Direct Numerical Simulation Reynolds Stress Heavy Particle Schmidt Number Light Particle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2007

Authors and Affiliations

  • A. M. P. Boelens
    • 1
  • L. M. Portela
    • 1
  1. 1.Department of Multi-Scale PhysicsDelft University of TechnologyDelftThe Netherlands

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