Modelling of gas-solid turbulent flows with non-spherical particles
In this presentation, I will discuss a computational model to simulate
the behaviour of turbulent flows laden with non-spherical particles of
large Stokes numbers. The computational model comprises different
elements. Firstly, the drag, torque and lift relations of each particle
shape is determined by means of DNS. A large number of simulations is
performed for each particle, to gather data on the drag, torque, and
lift on the particle under various Re numbers and angles of attack. All
these simulations are coarse-grained into drag, lift and torque correlations.
Secondly, the resulting relations are used in a fully coupled
point-particle approach of a horizontal channel flow using the large
eddy simulation (LES) framework. The horizontal channel flow properties
are based on the experimental and modeling work of Kussin and Sommerfeld
(2002). Three types of particles are studied: two types of ellipsoids
and disk-shaped particles.
Thirdly, to account for the high mass loading, a novel collision model
to deal with the collisions between non-spherical particles and the
particles and the wall is constructed based upon a Quaternion approach.
The simulations are compared to the available experimental data. The
results show there is a big effect of particle shape and particle
orientation. The effect of wall roughness one the particle flow and
orientation is discussed.
Some preliminary work is shown and discussed on modelling particles with
low Stokes number and their two-way coupling with the turbulence.