Wednesday - SAE

sae.org

Wednesday - SAE

Ansys develops strategic problem solving

According to the company,

high-performance CFD (computational

fluid dynamics) is

achieved in CFX-5, from Ansys,

Inc., by application of a cohesive

strategy in six key technology

areas: meshing, accuracy,

reliability, speed, physics, and

flexibility. Details of how these

features all come together are

available at Booth 846.

The meshing strategy is

flexible, because no single

strategy is ideal for every case.

Four element types—

hexahedral, tetrahedral, wedge

evolved over a 20-year period,

rooted first in CFX-TASCflow and

now in CFX-5. This is the only

linear solver available in the

program. It is fully automatic,

fully scalable (linear increase in

CPU time with problem size), and

insensitive to mesh aspect ratio.

All of this means the user

experiences fewer problems in

getting the desired computation

to run from start to end.

The latest version of CFX-5 will

be released in April, 2004 and

will contain many new features

that build upon high performance.

Turbulence model

control, one-way fluid-structure

interaction, and moving mesh are

just some of the new capabilities.

David Alexander

With CFX-5 from Ansys, Inc., a fully

transient turbulence model can solve

large eddy simulation of flow behind

a cylinder.

or prism, and pyramid—are

available, and from these

building blocks almost any style

of mesh is possible. The

program supplies its own

hybrid meshing technology,

and the result is near-automatic

best-practice CFD meshes that

resolve the geometry and the

boundary layer.

It also supports a large

number of external grid

formats. Combinations of

multiple mesh styles in a single

analysis can be done using the

general grid interface (GGI)

technology in CFX-5, developed

over a 12-year period in CFX-

TASCflow. For example, a hex

mesh created with ICEM Hexa

can be connected to a hybrid

unstructured mesh created with

the mesher.

A CFX-5 simulation involves

the solution of a set of coupled

nonlinear equations. The

nonlinear solution is obtained

by repeatedly updating and

solving a set of linearized

equations. There are many

approaches to achieve reliable

convergence, but the coupledmultigrid

method stands out.

The CFX multigrid-method has

Wednesday, March 10, 2004

See Us at SAE Show Booth #2143

7

More magazines by this user
Similar magazines