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Computational Fluid Dynamics Software

FLOW-3D
is a powerful and highly-accurate computational fluid dynamics (CFD)
software that gives engineers valuable insight into many physical flow
processes. With special capabilities for accurately predicting
free-surface flows, FLOW-3D is the ideal CFD software to use in your
design phase as well as in improving production processes.

FLOW-3D
is an all-inclusive package. No special additional modules for meshing
or post-processing are needed. An integrated graphical user interface
ties everything together, from problem setup to post-processing.

Free Gridding Separates Meshing from Geometry Construction
FLOW-3D
uses an approach to gridding that combines the advantages of simple
rectangular grids with the flexibility of deformed, body-fitted grids.
The approach is referred to as “free-gridding” because grids or
geometry can be freely changed, each independent of the other. This
feature eliminates the tedious task of generating body-fitted or
finite-element grids. FLOW-3D uses a fixed grid of rectangular control
elements because these are simple to generate and possess many
desirable properties (e.g., improved accuracy, smaller demands on
memory, and simpler numerical approximations).

Modeling Fluid Flow in Complex Geometry is Easy with FAVOR™
FLOW-3D
incorporates a special technique, known as the FAVOR™ (Fractional Area
Volume Obstacle Representation) method, which is used to define general
geometric regions within the rectangular grid. The philosophy behind
FAVOR™ is that numerical algorithms are based on information consisting
of only one pressure, one velocity, one temperature, etc., for each
control volume, so it would be inconsistent to use much more
information to define the geometry. Thus, the FAVOR™ technique retains
the simplicity of rectangular elements while representing complex
geometric shapes at a level consistent with the use of averaged flow
quantities within each volume element.

TruVOF and Free Surface Modeling
FLOW-3D
differs from other CFD programs in its treatment of flowing fluid
surfaces. The program uses special numerical methods to track the
location of surfaces and to apply the proper dynamic boundary
conditions at those surfaces. In FLOW-3D, free surfaces are modeled
with the Volume of Fluid (VOF) technique that was first developed by a
group of scientists, including Flow Science’s founder, Dr. C. W. Hirt,
at the Los Alamos National Laboratory. A number of competing CFD
programs claim to have incorporated a VOF capability, when in reality
they implement only one or two of the three fundamental VOF
ingredients. Prospective users of CFD should be aware that these
pseudo-VOF schemes will often give incorrect results. FLOW-3D has all
of the ingredients recommended for the successful treatment of free
surfaces. Moreover, FLOW-3D incorporates major improvements beyond the
original VOF method to increase the accuracy of boundary conditions and
the tracking of interfaces. We refer to our implementation as TruVOF.

Multi-Block Meshing for Efficiency and Speed
FLOW-3D
offers multi-block meshing, which is designed to add even more
flexibility and efficiency to the finite difference meshing technique.
In a standard finite difference mesh, local refinements may lead to a
substantial increase in the total number of cells since mesh lines
extend all the way to domain boundaries in all three directions. Use of
multiple blocks allows such refinements to be more localized, and
therefore requires fewer computer resources. The multi-block feature is
especially useful in so-called "rangy" problems, where features exist
that are small compared to the overall domain size, like small
obstacles and thin channels. Using multiple mesh blocks, a user can
"link" individual blocks to mesh a "rangy" domain and mesh only the
areas of interest and limit the total number of computational cells.
Using a "nested" block, a user can enhance the resolution around an
area of interest.

more info @http://www.flow3d.com/flow3d/