CFD Module
New Functionality in Version 6.4
Rotating frame property
A Rotating frame property has been added to the Physical Model section of the settings for the Creeping Flow, Laminar Flow, Turbulent Flow, Large Eddy Simulation, Detached Eddy Simulation, and Brinkman Equations interfaces. When selected, the velocity field is defined relative to a rotating frame by including the fictitious Coriolis, centrifugal, and Euler forces in the momentum equation and a global Rotating Frame feature, with settings for the Axis of rotation, Rotation speed, and Rotational direction, is automatically added to the physics interface.
Elliptic Blending Reynolds Stress Model
The new turbulence model Elliptic Blending R-ε has been added under Turbulence model when the Turbulence model type is chosen as RANS-RSM. Model Wizard entries have been added for the Single-Phase Flow, Nonisothermal Flow, and High Mach Number Flow interfaces. This Reynolds stress model applies blending of near-wall and far-field expressions for the pressure–strain correlation and the turbulence dissipation rate to generate more accurate results for the Reynolds stresses in the near-wall region.
NEW reynolds-stress diffusion models for RANS-RSM
The Reynolds-stress diffusion model in the RANS-RSM interfaces has four predefined options: Daly–Harlow, Hanjalic–Launder, Mellor–Herring, and Lumley.
Scale-adaptive turbulent flow simulations
The Turbulent Flow, SST interface has a new option to Include scale-adaptive simulations. By including the von Kármán length scale, a broader range of turbulent scales can be resolved in unsteady RANS simulations.
rotation–curvature correction FOR eddy viscosity models
The two- and three-equation RANS-EVM models have a new option to Include rotation–curvature correction. Streamline-curvature and system-rotation effects are taken into account by modifying the production rates for the turbulence kinetic energy, and the turbulence dissipation rate or the specific turbulence dissipation rate.
algebraic turbulence models in rotating machinery, high mach number flow Interfaces
Two new Turbulent Flow interfaces, High Mach Number Flow, Algebraic yPlus and High Mach Number Flow, L-VEL, have been added under Rotating Machinery, High Mach Number Flow branch in the Model Wizard. Solutions obtained with algebraic turbulence models can often provide good initial values for simulations with more complex turbulence models.
Anisotropic thermal turbulence models
In the Nonisothermal Flow and Reacting Flow multiphysics couplings as well as in the High Mach Number Flow interfaces, it is now possible to use anisotropic thermal turbulence models. The Generalized Gradient-Diffusion Hypothesis (GGDH) model and its high-order extension (HO-GGDH) are now available to model the anisotropy of the turbulence with respect to the heat equation. These models rely on the Reynolds stress tensor and therefore require a RANS-RSM model to account for turbulence anisotropy in the momentum equation.
nonisothermal reacting flow large eddy simulations
Three Large Eddy Simulation interfaces, LES RBVM, LES RBVMWV, and LES Smagorinsky, have been added to the Model Wizard in the Chemical Species Transport branch under Nonisothermal Reacting Flow. These physics interfaces simulate fluid flow with mass and heat transfer in the turbulent regime and apply large eddy simulation (LES) modeling for the unresolved scales of all three physics. In addition to a license for the CFD Module, these interfaces require a license for either the Chemical Reaction Engineering Module, the Battery Design Module, or the Fuel Cell & Electrolyzer Module.
fluid–structure interaction coupling for boundaries between free and porous domains
The Fluid–Structure Interaction multiphysics coupling node is now also applicable on boundaries between free-flow domains and porous-media domains. This enables studies of the interaction between free-flow and poroelastic domains.
marangoni effect for concentration gradients
In the Free Surface, Stationary Free Surface, and Fluid-Fluid Interface features, the Surface tension coefficient list has the new option Library coefficient, liquid mixture/gas interface, with a selection of predefined binary liquid mixtures. When a Transport of Concentrated Species or Transport of Diluted Species interface is active in the component, the appropriate interface selection can alternatively be selected to apply the surface tension values of each corresponding species, which applies the mass fraction or concentration from the corresponding species transport interface.
predefined loss options in the grillE Boundary Condition
The Flow condition setting in the Grille boundary condition has the new option Grille type, with predefined models for Wire gauze, Square mesh, and Perforated plate.
pressure jump in the free and porous media flow coupling
The Free and Porous Media Flow Coupling multiphysics coupling node has a new option to Include pressure jump across free–porous boundary.
user-defined inertial resistance coefficient for non-darcian flow
When the Flow model in the Porous Medium feature is set to Non-Darcian, the Porous Matrix subnode has a new option to specify a user-defined Inertial resistance coefficient.
Corrected Implementation of Contact Angles in the Wetted Wall Feature in the Ternary Phase Field Interface
An error in the implementation of the Ternary Phase Field interface’s Wetted Wall feature, which resulted in the wrong contact angle between the phases A and B when the three surface-tension coefficients were not identical, has been corrected. As a result, the definitions of the contact angles now agree with the figure shown in the feature’s Settings window.