1D-3D computational fluid dynamics software is first for industry
Computational Fluid Dynamics (CFD) has been used by specialists for years to analyse fluid (liquids and gases) flows and heat transfer of complex mechanical systems. However, today's pressures to bring products to market faster and at reduced cost means that mechanical CAD designers and engineers, in addition to specialists, be able to perform these analyses directly in their mechanical design system.
3D CFD has thus become an intrinsic part of many CAD packages. One of the leading suppliers of this CFD has been Mentor Graphics, whose FloEFD is embedded in both Siemens' CATIA and PTC's Pro/Engineer. By embedding such a sophisticated component analysis program within the user's preferred CAD package at the earliest stages of design, it is argued, cuts the number of costly physical prototypes, and reduces simulation time by 65-75%.
A complementary, but (until now) discrete technology is 1D CFD for the analysis of complex engineering. Following its acquisition of the UK-based Flowmaster Group this year, Mentor Graphics now owns the Flowmaster 1D CFD solution, a fact that has led to it coupling 1D and 3D technologies in a commercially-available, general-purpose 1D-3D native CFD solution.
Traditionally, 1D and 3D CFD have had very distinct advantages, which has led them to be considered incompatible. Systems engineers commonly use 1D and 3D CFD software in the automotive, aviation, oil, gas, power and energy industries. For designing complex systems, 3D CFD would be extremely accurate but it can be computationally expensive depending on the size of models used. Therefore, 1D CFD is used, which is faster, but may require significant amounts of data to characterise the components accurately.
By integrating highly detailed snapshots of 3D component analysis within the 1D system-level models, Mentor Graphics is now able to provide higher accuracy for the components while minimising the resources and execution times required.
The difficulty in developing this new system, according to Flowmaster's product line director Morgan Jenkins, was in uniting the two technologies without compromising either. "When we started this process following the acquisition, the original idea was to achieve some sort of co-simulation," he says. "However, it soon became clear that, when the two systems run together, they can only run at the speed of the slower. This solution was designed to decouple the two to prevent compromise. The 3D characterisation is stored in Flowmaster's relational database and can be used in future models, but is essentially a snapshot and is not slowing down the other system."
This, it is felt will have a hugely beneficial impact on design projects, allowing much more seamless collaboration with ever greater access to detailed information. Says Jenkins: "A powertrain engineer may need a virtual representation of the engine within the system diagram. Once upon a time, they would have gone to a dedicated MCAD engineer to get a 3D virtual prototype. By reducing the amount of time taken to get essential component information to system designers, it smoothes the design process enormously."
