Modellgalerie
Turbulent Flow over a Backward-Facing Step
The backward facing step is an interesting case for studying the performance and solution strategy of a turbulence model. In this case, the flow is subjected to a sudden increase of cross-sectional area, resulting in a separation of flow starting at the point of expansion. Spatial variations in the velocity field cause production of turbulence outside the wall region and its interaction with ...
Swirl Flow Around a Rotating Disk
Swirl flow is an application that involves steady rotational flow around an axis. Rather than modeling this process in 3D, COMSOL Multiphysics provides a 2D axisymmetric interface where the flow in the rotational direction is still included in the equations. This example shows the effect of a rotating cylinder on the flow in a container. Such applications are often used in chemical kinetic ...
Phase Separation
Phase separation occurs when a binary system is quenched from its stable, homogeneous one-phase state into the two-phase region of its phase diagram. The spontaneous separation of two immiscible fluids is sometimes referred to as spinodal decomposition. Each phase tends to separate into pure components. This benchmark model takes two initially mixed, immiscible phases and observes their ...
Viscous Heating in a Fluid Damper
Fluid dampers are used in military devices for shock isolation and in civil structures for suppressing earthquake-induced shaking and wind-induced vibrations, among many other applications. Fluid dampers work by dissipating the mechanical energy into heat. This model shows the phenomenon of viscous heating and consequent temperature increase in a fluid damper. Viscous heating is also important in ...
Transonic Flow in a Sajben Diffuser
In this model the high speed turbulent gas flow in a converging and diverging nozzle is modeled using the High Mach Number Flow interface. The diffuser is transonic in the sense that the flow at the inlet is subsonic, but due to the contraction and the low outlet pressure, the flow accelerates and becomes sonic (Ma = 1) in the throat of the nozzle. After a short region of supersonic flow, a ...
Non-Newtonian Flow
This model shows the influence of shear rate dependent viscosity on the flow of a linear polystyrene solution. For this type of flow, you can use the Carreau viscosity model. Due to rotational symmetry, it is possible to reduce the model dimensions from 3D to axisymmetric 2D.
Separation Through Electrocoalescence
Applying an electric field across a suspension of immiscible liquids may stimulate droplets of the same phase to coalesce. The method known as electrocoalescence has important applications, for instance, in the separation of oil from water. To model electrocoalescence, you need to solve the Navier-Stokes equations, describing the fluid motion, as well as track the interfaces between the ...
Turbulent Mixing of a Trace Species
This tutorial model demonstrates how mixing can be visualized in a stirred vessel by seeding a trace species from a point. The flow is modeled using the Rotating Machinery, Fluid Flow physics which solves Navier-Stokes equations on geometries with rotating parts, for example impellers. The transport of the trace species is modeled using the Transport of Diluted Species physics.
Syngas Combustion in a Round-Jet Burner
The model simulates non-premixed turbulent combustion of syngas (synthesis gas) in a simple round-jet burner. Syngas is a gas mixture, primarily composed of hydrogen, carbon monoxide and carbon dioxide. The name syngas relates to its use in creating synthetic natural gas. In the model, syngas is fed from a pipe into an open region with a slow co-flow of air. Upon exiting the pipe, the syngas ...
The Magnus Effect
The Magnus effect explains the curl that soccer players can give the ball, resulting in the enjoyable goals that we can see in every World Cup™. This model looks at the Magnus effect in the laminar and turbulent flow regimes for transient and stationary flows. It also discusses the simulation results and relates them to experimental measurements on soccer balls found in the literature.
