The Effort of Increasing Reynolds Number in Projection-Based Reduced Order Methods: from Laminar to Turbulent Flows
This is an incremental contribution for computational fluid dynamics practitioners seeking efficient reduced order models for turbulent flows.
The paper presents two reduced order strategies for Navier-Stokes equations across varying Reynolds numbers, with a new POD-Galerkin approach for turbulent flows that incorporates eddy viscosity online via interpolation. The methods are tested on benchmark cases, but no concrete numerical results are reported.
We present two different reduced order strategies for incompressible parameterized Navier-Stokes equations characterized by varying Reynolds numbers. The first strategy deals with low Reynolds number (laminar flow) and is based on a stabilized finite element method during the offline stage followed by a Galerkin projection on reduced basis spaces generated by a greedy algorithm. The second methodology is based on a full order finite volume discretization. The latter methodology will be used for flows with moderate to high Reynolds number characterized by turbulent patterns. For the treatment of the mentioned turbulent flows at the reduced order level, a new POD-Galerkin approach is proposed. The new approach takes into consideration the contribution of the eddy viscosity also during the online stage and is based on the use of interpolation. The two methodologies are tested on classic benchmark test cases.