Characterization and modeling of complex fluid flow inside a stirred tank

In the context of complex fluid process development (bio-process, water treatment, material synthesis, plastic recycling), a thesis is suggested in order to study and model the local shear distribution in mixing unit for Reynolds numbers in between 2000 <Re<20000. Actually, some works are in progress concerning the impact of a homogeneous shear field on a complex fluid. This thesis will complete these works  with the objective to study a complex flow in industrial reactor with an heterogeneous shear field. This latter will be characterized using a stirred tank with a transparent non newtonian fluid by Particle Image Velocimetry (PIV).
The reactor hydrodynamic modeling (CFD) will be performed simultaneously with the experiments. A first step will consist in LES (Large Eddy Simulations) simulations in order to simulate a sufficiently small scale to observe the impact of the local shear rate on the fluid rheology. The second step of the modeling study will be centered on the scale-up of the mixing process with a qualification of RANS (Reynolds Average Navier-Stokes Simulation) models more appropriated to large scale due to their lower calculation cost. If possible, the objective of the end of the thesis would be to couple the CFD with a population balance model that will govern the complex rheology of the fluid.
This thesis subject, highly transversal, will participate in the understanding of scale-up mixing process with complex fluid and promote development of innovative technologies.

Keywords: complex fluids, turbulence, agitation

• Academic supervisor    MORCHAIN Jérôme, Toulouse Biotechnology Institute, AUGIER Frédéric, IFPEN
• Doctoral School    ED468, MEGeP, https://www.univ-tlse3.fr/mecanique-energetique-genie-civil-procedes
• IFPEN supervisor    SERVEL Marion, Conception et modélisation des procédés, marion.servel@ifpen.fr
• PhD location    Toulouse Biotechnology Institute, Toulouse, France  
• Duration and start date    3 years, starting in fourth quarter 2021
• Employer    IFPEN, Lyon, France
• Academic requirements    University Master degree
• Language requirements    Fluency in French or English