We study a new hybrid RANS/Variational Multiscale LES (VMS-LES) model for bluff body flows. The simulations have been carried out using a parallelized solver, based on a mixed element/volume formulation on unstructured grids. First, the behavior of a VMS-LES model with different subgrid scale models is investigated for the flow past a circular cylinder at Reynolds number Re =3900. Second, a new...

This paper presents computational results for two DES (Detached Eddy Simulation), one hybrid RANS (Reynolds Averaged Navier-Stokes)/ LES (Large Eddy Simulation) and some preliminary results from PANS (Partially Averaged Navier-Stokes) turbulence for simulation of unsteady separated turbulent flows. The models are implemented in a full 3-D Navier Stokes solver and are based on the twoequation k-...

Combustion is a natural phenomenon. It happens in forest, automotive engine and gas cooker. In Computational Fluid Dynamics (CFD), the combustion phenomenon complies with a set of partial differential equations. According to the resolution scale, from big to small, the simulation methods in combustion are Reynolds Averaged Navior Stokes method (RANS), Large Eddy Simulation (LES), and Direct Num...

DRDC Atlantic is collaborating with ANSYS Canada and the University of New Brunswick to develop an unsteady, six degrees-of-freedom, Reynolds Averaged Navier-Stokes (RANS) submarine maneuvering simulation capability. Initially, this is being used to evaluate emergency rising maneuvers. During these maneuvers, high negative angles of attack can occur which result in a roll instability not previo...

The gas turbine presents significant challenges to any computational fluid dynamics techniques. The combination of a wide range of flow phenomena with complex geometry is difficult to model in the context of Reynolds-averaged Navier–Stokes (RANS) solvers. We review the potential for large eddy simulation (LES) in modelling the flow in the different components of the gas turbine during a practic...

The requirement that physical quantities not vary with a hybrid LESRANS model’s blending parameter imposes conditions on the computation that lead to better results across LES-RANS transitions. This promises to allow placement of those transitions so that LES is performed only where required by the physics, improving computational efficiency. The approach is applied to separated flow past perio...

Full-scale experimental and computational fluid dynamics (CFD) methods were used to investigate buoyancy-driven single-sided natural ventilation with large openings. Detailed airflow characteristics inside and outside of the room and the ventilation rate were measured. The experimental data were used to validate two CFD models: Reynolds averaged Navier-Stokes equation (RANS) modeling and large ...

The gas turbine presents significant challenges to any computational fluid dynamics techniques. The combination of a wide range of flow phenomena with complex geometry is difficult to model in the context of Reynolds-averaged Navier–Stokes (RANS) solvers. We review the potential for large eddy simulation (LES) in modelling the flow in the different components of the gas turbine during a practic...

The gas turbine presents significant challenges to any computational fluid dynamics techniques. The combination of a wide range of flow phenomena with complex geometry is difficult to model in the context of Reynolds-averaged Navier-Stokes (RANS) solvers. We review the potential for large eddy simulation (LES) in modelling the flow in the different components of the gas turbine during a practic...