PR-DNS at MSME

During the year 2023, I did an internship in the TCM team of MSME laboratory at Gustave Eiffel University.

 

In this research project, I worked in the development branch of ellipsoidal particles of the PR-DNS code of solid-gas flows ’RESPECT-FUGU’. That is to fully resolve the flow around particles to provide closures for larger models.

 

The aim is to extend the code to an ellipsoidal nature of particles by managing orientation. The approach followed is twofold. Firstly, the angular velocity of the particle is accounted for in a Lagrangian way in the world-space frame.  

Secondly, by knowing the angular velocity, a particle’s
angular position can be fully described by a one-to-one relationship with a unit quaternion which is numerically
superior to other rotation representations. By means of two methods to integrate the latter, a comparative study showed that a direct multiplication of quaternions combined with a 2-order midpoint scheme has the best order of convergence.

 

Ultimately, we run simulations to validate the aforementioned developments, by taking a particle in a simple shear flow based on Jeffery's orbits. (1923)

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Our model is in good agreement with the analytical periodic solution at the limit of small particle Reynolds
numbers Rep < 0.1.