CARPET 4:
Application of Large Eddie Simulation (LES) in reactor modeling.

Objectives:

To formulate and validate a Large Eddy Simulation (LES) model for chemical reactors based on the multi-fluid concept.

Focus will be on the model formulation, basic model assumptions, physical considerations and validation of modules for introducing Large Eddy Simulations in the generalized chemical reactor model frame.

Background:

For describing turbulent multiphase flows different modeling approaches can be applied. In some papers a practice similar to Reynolds averaging have been applied whereas others use a practice similar to Favre averaging. Lately, the Large Eddy Simulation approach has been mentioned as a future tool for dis-persed multiphase flows. There is thus some controversy as to which of these turbulence modeling procedures is preferable for modeling multiphase chemical reactors.

Scope of work:

The potential for the application of LES in reactor technology will be evalu-ated.

Existent mathematical formulations will be evaluated aiming for an accurate algorithm suitable for characteristic conditions in chemical reactors. The experimental framework for validation will be discussed.

The work is intended to result in formulations applicable for reactor models where the interactions between flow and chemical mechanisms of very differ-ent scales can be handled. Both conditions where the reaction rates are much faster, at the same order and much slower than the turbulence scales are to be analyzed.

PhD student:

Thomas Braseth

Affiliation:

NTNU, Department of Applied Mechanics, Thermo- and Fluid Dynamics.

Supervisors:

Stein T. Johansen in colloaboration with Hugo A. Jakobsen, Trond Kvamsdal, Reidar Kristoffersen, John Morud , and Knut Bech.