Finally Flowing

Until recently, flow simulation was not available in CATIA 5. All that has now changed: With the new software from NIKA, developers can perform the relevant calculations themselves.

Internally incompressible air flow in an exhaust gas catalytic converter. Pictures: NIKA » more pictures in our gallery

Product Lifecycle Management (PLM) software includes an almost complete range of modules for a wide variety of simulation tasks. In some cases, the software suppliers develop these components directly, while in others specialist third-party providers integrate their latest technologies into the corresponding PLM platform. For CATIA V5 from Dassault Systèmes, which is widely used in the automotive industry, numerous simulation modules are already available. However, until very recently there was still a gap in the range of technical calculation software: there was no module for simulating flow and heat/material transfer. This was despite the fact that a great many products and components are based on these very processes. An optimised design is often the unique selling point for these products. Enter the Frankfurt software house NIKA, whose new EFD.V5 application has succeeded in closing this gap. The name stands for “Engineering Fluid Dynamics for CATIA V5” and refers to its differentiation from traditional “Computational Fluid Dynamics” (CFD) software. Flow around a car: In the automotive industry, many products and components benefit from the use of fluid and thermal dynamics calculations. Picture: NIKA Complex Physical Flows There is no doubt that flow and heat transfer processes are much harder to understand and far less accessible than other calculations, for example those relating to strength or deformation. They are extremely complex, which is reflected in the elaborate system of mathematical equations involved in simulation. Sophisticated techniques are necessary to achieve high-quality results in practice. The EFD method therefore includes all the technical elements necessary to produce the convenient process-oriented flow simulations that are an integral part of digital product development. Reduced-function versions of conventional CFD programs with formal links to a CAD system are no longer a viable alternative. The software is designed to allow the development engineer to concentrate totally and solely on his technical and physical tasks. The routine jobs in a simulation project should run fully automatically and all activities that call for special knowledge from another discipline are cut to a minimum. Markus Bittcher from TRW Automotive Electronics and Components has already gained some experience of using the software and commented that: “I am the user of the software, not its slave.”

Development and Calculation on One Workstation At present, engineering calculations such as flow simulations are normally performed in special calculation departments, which are organisationally and, in many cases, financially separate from the development and design departments. Not so with the PLM strategy. Here, employees from development and calculation split the tasks according to their scope and complexity. It is of considerable benefit for developers to be able to perform flow calculations using the new EFD tool from NIKA on their PLM workstation. It allows the new findings to be integrated into the development process at the correct point and the right time.

Huge Productivity Potential The results of flow and heat transfer simulations with EFD.V5 always provide a complete image of the physical flow processes. They also include variables such as fluid speeds, pressures, temperatures, volumetric and mass flow rates and the forces and moments acting on components. As a result, the engineer obtains a comprehensive physical understanding of the flow relationships in the relevant component or assembly. He can virtually move around the flow space and visually evaluate critical areas in the CAD model. These possibilities provide huge productivity potential for decision-making at early stages of the development process and for preliminary selection of design options or demonstration of the physical and technical functional capabilities of the selected design. EFD.V5 has a broad range of applications. According to NIKA there is only one practical limit on the complexity of the design to be investigated: the available computer resources. The program is available from a price of 19,500 Euro. Typical applications in automotive engineering include cooling tasks in the drive train, design of intake and exhaust systems, optimisation of flow into and through catalytic converters and the configuration of air-conditioning systems and their components. Flow simulation is also used in dimensioning and optimisation of filters, valves and heat exchangers and as part of fundamental studies of alternative technologies such as fuel cells.