• The opportunity to meet employees of the CD adapco Group and fellow users
• Presentations about new features of STAR-CD
• Presentations on a variety of STAR-CD applications given by users from across all industries
• An exhibition by our hardware and software partners
• Evening entertainment

CFX-5.5 offers a number of improvements over previous versions including:

• Improved meshing with proximity detection and general interface support
• Improved multiphase modeling
• Free surface modeling
• Single and multiple step chemical reaction models
• Multiple frame of reference modeling
• Advanced turbulence modeling including a Shear Stress Transport (SST) model
• A new post-processor featuring a scripting language

CFX-5.5 combines the world-class meshing and solver technology of earlier CFX-5 releases with new physical modeling, meshing and post-processing tools that make it possible to apply the most powerful and precise CFD technology to a very broad range of problems. -- Chris Reid, President and Chief Executive Officer of CFX

Gillian Rowe
AEA Technology
The Gemini Building, Fermi Avenue
Harwell International Business Centre
Didcot
Oxon
OX11 0QR
Tel: 01235 448035
Fax:. 01235 448001
Email: gilian.rowe@cfx.aeat.com

The naval and commercial ship design communities have long needed a predictive capability to address the complex interaction between a ship's boundary layer, the nonlinear free-surface, and the propulsor. In commercial ship design, the prediction of near-field flows is central to the problems of unsteady propeller loads, cavitation, and propeller-induced hull vibrations. The solution to these problems requires detailed knowledge of the turbulent stern flow (including thick and perhaps separated boundary layers), bilge vorticity, and propeller/hull interaction.

Another interesting application is the prediction of ship hydrodynamic response, how the ship pitches and rolls, in heavy seas.

There are several CFD codes available which are tailored for hydraulic analysis.

The use of CFD in the ship building industry has been spured by the expense and time-consuming nature of hydrodynamic tank testing.

Although many boat parts are now totally computer designed, for some key parts, such as the hull, there is still no substitute for the traditional method of physically building models and testing them in tow tanks.

Typical fluid-structure interation (FSI) simulations attempt to couple the full structural analysis FEA code with the CFD solver and compute the structural stresses and deformations after each iteration. The approach taken in the EZ_FSI product takes advantage of a lumped-mass model of the solid part to simplify the analysis.

First, the solid part is meshed and the fluid-structure interaction points (the "wetted" points) are identified. The solid part is then analyzed to determine lumped mass, damping, and stiffness values for the wetted points. The lumped system will behave exactly as the full system for linear systems with small deformations.

Next, the fluid portion of the domain is meshed and the fluid structure interaction points are identified as a special moving boundary. As the transient, CFD solution progresses, the pressure on the wetted points is used as a forcing function on the lumped mass system to determine the new location at the current time. The boundary is moved to the new location, the CFD mesh is updated, and the process repeats. This is all done within the CFD solver -- eliminating the need to communicate with an external structural analysis package every iteration.

Finally, after completing the CFD analysis, the transient pressure data can be imported into the structural analysis package to determine dynamic stresses within the solid.