Creating Open Design Environments through Tighter Integration of Tools and Analysis Types

Bob Williams
Product Manager
ALGOR, Inc.
Pittsburgh, PA

This article was originally published in Design News, "Focus on Openness", October 25, 2004.

What is the hottest general trend in simulation today? There are two emerging trends: 1) tighter integration between all the tools that engineers use; and 2) tighter integration between analysis types for multiphysics.

A new focus is the creation of open design environments through the implementation of open architecture technology and industry-standard data formats that are flexible enough to incorporate any type of software that an engineer might need. Creating an open design environment could be as simple as enabling users to access their frequently used applications through the CAE software. Users could also use built-in scripting tools and plug-in support to automate data transfer and format conversions between applications. For example, ALGOR customers can work with third-party fatigue analysis tools through an Add-In Manager and directly import material data from on-line sources such as MatWeb.com through an industry-leading XML format. In addition, our products provide full compatibility with industry-standard NASTRAN input and output files.

Another trend in the CAE industry is to more tightly integrate multiphysics analysis capabilities into a single process so that engineers can simulate an entire scenario that incorporates the whole product and the environment in which it will be used. CAE vendors are working to make their software support all desired analysis types within the same user interface; easily couple results from one analysis type to another; and simulate motion as well as standard multiphysics effects.

Why are these trends? Both trends are driven by the same need – increased user productivity. Today, it's understood that simulation tools communicate directly with CAD and are easier to use. This makes users more productive because it takes less time to define models for analysis. Now, users are looking to expand what they do with simulation tools and simply want all of their design and simulation tools to communicate directly and easily. They also want to consider more than just the structural loads acting on a model, so heat, fluid flow and other multiphysics effects are increasingly considered. Thus, today's trends are a natural progression from recent developments.

Simulation is a term we hear a lot lately. Hardly anyone says FEA anymore. What's the difference, if any, between simulation and FEA? Simulation is what you do – you perform a simulation of a real-world event on the computer. FEA is one of the tools that lets you perform simulation. A kinematics package, for example, is another simulation tool.

Is it possible – or even advisable – to begin a design in a simulation package and bypass CAD as the first step in the process? In other words, would it make sense for an engineer to go straight to a simulation model from his paper-napkin sketch of a new design idea? As CAE vendors, our goal is to simply give users tools that allow them to work the way they need. That's why ALGOR, for example, provides extensive CAD support features as well as the option for users to do all their 2- and 3-D sketching, modeling and structured meshing directly within FEA. We provide flexibility and then it's up to users to decide what's best for them. As an example, users commonly bypass CAD to do a first-pass analysis using a quick, 2-D proof-of-concept model.

What should an engineer do if the answers that his simulation or FEA runs give him conflict with what his experience tells him should be the answer? You need to step back, re-evaluate your approach to the simulation and make sure you've set up a proper model. FEA is a powerful tool, but, if given bad input, it will output bad results. Given a properly defined model though, benchmark tests have proven FEA can predict real-world behavior. However, it is often difficult to know what the loads and constraints should be, particularly for scenarios involving motion, impact, time-dependent changes or multiphysics phenomena.

To avoid these difficulties, for example, ALGOR's Mechanical Event Simulation (MES) combines large-scale motion and stress analysis and uses nonlinear time-dependent FEA to properly account for the changing inertia, shape and material behavior of the model as it undergoes motion or experiences impact. With MES, there is no need to calculate or approximate loads because the forces and moments are automatically balanced according to Newton's laws of motion.

Is FEA at the point where non-engineers could use it easily and with confidence in the results? Yes, non-engineers are also using FEA for productive work in diverse fields such as anthropology, dentistry and medical research as illustrated by the following examples:

• David S. Strait, Ph.D., anthropologist and assistant professor at the New York College of Osteopathic Medicine of the New York Institute of Technology, used ALGOR's linear static stress analysis to determine how the skull of a crab-eating macaque monkey resists chewing loads. The purpose of the study was to examine the functional anatomy and evolution of the facial skeleton in primates.
• Dr. Robert Park of the Ophthalmic Consultants of Boston and the Tufts University School of Medicine used ALGOR's Mechanical Event Simulation to determine the peak stresses generated in the human eye as it undergoes a rapid point-to-point rotation of 30 degrees. This research could lead to improved techniques for the repair and prevention of retinal detachments.

What's on the horizon? What will FEA and simulation technology be like in the future? What new problems will it be able to solve? How much faster can it get? Open design environments and improved simulation technologies will lead to true virtual prototyping, in which CAD assemblies of entire products are used in simulations including all of the environmental factors a product may experience. No longer will users analyze one instant in time as with linear static stress analysis; instead, simulation will routinely include large-scale motion, impact and stress analysis while also considering other multiphysics effects. Growing computing power will speed up the processing of simulations, which will allow users to see results in real time and focus on the accurate representation of products. Animated results of virtual prototypes will show a product’s behavior in a particular scenario, rather than just producing numerical results that need to be interpreted. As computer graphic technologies become more realistic, virtual prototypes will look increasingly like a video of a physical prototype test.

By seeing the behavior of a design on the computer, engineers will develop useful, real-world insights into their designs and reduce expensive and time-consuming physical prototype testing, thus lowering cost and time to market.