The objective of this work is to show a procedure for mesh generation in a fluidized bed using large eddy simulations (LES) of a filtered two-fluid model. The experimental data were obtained by [1] in a laboratory fluidized bed. Results show that it is possible to use mesh with less cells as compared to RANS turbulence model with granular kinetic theory flow (KTGF). Also, the numerical results ...

A blade element momentum theory propeller model is coupled with a commercial RANS solver. This allows the fully appended self propulsion of the autonomous underwater vehicle Autosub 3 to be considered. The quasi-steady propeller model has been developed to allow for circumferential and radial variations in axial and tangential inflow. The non-uniform inflow is due to control surface deflections...

Prediction of particle transport in enclosed environment is crucial to the welfare of its occupants. The prediction requires not only a reliable particle model but also an accurate flow model. This paper introduces two categories of flow models – Reynolds Averaged Navier-Stokes equation modeling (RANS modeling) and Large Eddy Simulation (LES); as well as two popular particle models – Lagrangian...

Inspired by the remarkable performance of the Leray-α (and the Navier–Stokes alpha (NS-α), also known as the viscous Camassa–Holm) subgrid scale model of turbulence as a closure model to Reynolds averaged equations (RANS) for flows in turbulent channels and pipes, we introduce in this paper another subgrid scale model of turbulence, the modified Leray-α (ML-α) subgrid scale model of turbulence....

In this study, turbulent compressible gas flow in a rectangular micro-channel is numerically investigated. The gas flow assumed to be in the subsonic regime up to Mach number about 0.7. Five low and high Reynolds number RANS turbulence models are used for modeling the turbulent flow. Two types of mesh are generated depending on the employed turbulence model. The computations are performed for R...

In this paper, CFD simulation results for a tanker model are compared with experimental data over a range of wave conditions to verify a capability to predict the sea-keeping performance of practical hull forms. CFD simulations are conducted using WISDAM-X code which is capable of unsteady RANS calculations in arbitrary wave conditions. Comparisons are made of unsteady surface pressures, added ...

Simulations of compressible boundary layer flow at three different Reynolds numbers (Reδ = 5.59×10, 1.78×10, and 1.58×10) are performed using a hybrid large-eddy/Reynoldsaveraged Navier-Stokes method. Variations in the recycling/rescaling method, the higherorder extension, the choice of primitive variables, the RANS/LES transition parameters, and the mesh resolution are considered in order to a...

With the ever rising need for better fuel efficiency and lower emissions, the development of better engine technology is essential. Different strategies are being considered to increase engine efficiency, such as direct injection or downsizing. Certain regimes are clearly identified as optimal for certain range of loads. For gasoline engines, the Homogeneous Charge Compression Ignition (HCCI) c...

While Reynolds-averaged Navier-Stokes (RANS) simulations remain the most affordable technique for simulating complex turbulent flows, the inability of linear eddy viscosity models to correctly predict flow separation and reattachment limits the reliability of the simulation outcome. A methodology to quantify the uncertainty in the simulation outcome related to the form of the turbulence model u...