Why you don’t need heavy lifting simulation early in design.
This un-optimized camera saw quick initial optimizations after little effort and training.
No one is going to tell you that SolidWorks Simulation is a simulation powerhouse; it isn’t trying to be. The key to the software’s success isn’t eye popping feats like multiphysics, high cell counts, adjunct solvers, or fancy meshing tools seen in COMSOL, STAR-CCM+, ANSYS, and Simulia. SolidWorks Simulation instead brings the power of simulation into a CAD environment and therefore the initial design stages. This offers simple, cheap, quick methods for designers and design engineers to make more informed early decisions producing an overall more optimized product. After all, sometimes it’s David that really beats Goliath.
Simulation Early in Design
“When analysis started hitting the mainstream in the 80’s, it was something done at the end of the process,” said SolidWorks Simulation expert Glenn Whyte, a Simulation Product Manager at Hawk Ridge Systems. “You build the plane at Boeing and just before your flight you run an analysis that was pass or fail. Pass you are good to go; fail you move right back to the start again.”
Simulation at the start of the design process, however, means that you are able to test every decision along the development cycle. Design engineers are no longer over engineering a piece to ensure it passes the analyst’s muster. Instead through quick guess and check, they are optimizing the material, manufacturing process, cost, and even environmental impact by performing simple simulations.
What the Program Can Do
Depiction of Simulation Program’s complexity and target users as described by Glenn Whyte.
“We look in the industry and see differences in expertise requirements from designers, to design engineers, to full time simulation engineers and pure analysts. We see SolidWorks as a design to engineering tool. One of the main advantages of it is that it is integrated into CAD during the design workflow. This will shorten the learning curve. We explain to our customers that have never done analysis before that they can analyze 4-5 different scenarios in an hour. Just by manipulating the CAD, processing the analysis, and keeping track of what those changes mean physically. Simulations are also completely integrated with the CAD model, if you make a design change then it is ready to analyze without intermediate steps like file exporting. It will also use the existing mesh settings to re-mesh the model,” said Whyte.
Chart automatically keeps track of the optimization after every simulation.
He wasn’t exaggerating. During a live demo two engineers in training, with little experience in SolidWorks Simulation, were able to run about a dozen simulations each in an optimization challenge. Having applied their knowledge of the CAD environment they were able to optimize the safety factor of a camera mount by limiting the mass of the mounting panel. Meanwhile, a chart kept track of results of each simulation run.
Whyte said that SolidWorks Simulation “goes into some fair depth like non-linear dynamic analysis and it has a very capable CFD tool. We can draw different stratification for CFD and see how things will stack up differently. But when you go into highly non-linear, multiphysics, and highly dynamic problems we get close to the limit of our solver’s abilities. This is when you pick up ABAQUS, LS-Dyna, or Marc”
He has a fair point. It doesn’t make sense to run a simple problem in more complicated simulation programs. Setting up the program, exporting the files and fixing the geometry can take hours before you even run the simulation. In SolidWorks it will take no more than 5 minutes. Additionally, subsequent simulation set up is as simple as altering the CAD model.
“There is a productivity boost,” said Whyte. “If you are doing an analysis that fits in the assumptions made by the linear static stress analysis, which is 80% of the analysis done out there today, tools like the analysis capabilities we have in SolidWorks Premium are the most productive way to get a result, and our Simulation Professional and Simulation Premium packages can then take you a little further.”
No Frills Means Easy to Use
“Our developers have made a conscious decision to utilize easy to mesh element types and algorithms. We have five different mesh elements we can use but most solid body analysis is done with tetrahedrons. They get good results in most situations and they are very easy to write meshing algorithms for … We also retain control with adaptive meshing techniques where the mesh will change dependent on the stress gradients,” said Whyte.
Additionally, tools like linked multiphysics can certainly ensure that the final designs are completely optimized for final users. However, setting up such an analysis can take time and skills of a full simulation analyst.
Eliminating these tools may hurt the ability to completely optimize the problem but they are necessary to ensure designers and design engineers can use simulation properly. Besides, these “frills” fulfill a task much farther down the development cycle than initial design. At the initial design stages performing separate quick and easy physics simulations can be useful to limit the final designs destined for analysts to a short list saving time and money.
Make sure you buy the Right Thing!
As seen in the chart below, perhaps the most confusing thing about the SolidWorks packages is the naming convention. Though Dassault Systemes’ top design tool SolidWorks Premium does include simulation, it is the basic version which only includes linear static simulations in assemblies and time based motion simulations.
However, this package can be extended with additional analysis types available in SolidWorks Simulation Professional and SolidWorks Simulation Premium, like fatigue, frequency, nonlinear and dynamic analysis.
Analysis | SolidWorks Premium | SolidWorks Simulation Professional | SolidWorks Simulation Premium | SolidWorks Flow Simulation |
---|---|---|---|---|
Static Stress | X | X | X | |
Time-Based Kinematics | X | X | X | |
Event-Based Kinematics | X | X | ||
Optimization | X | X | ||
Thermal | X | X | ||
Sub Modeling | X | X | ||
Fatigue | X | X | ||
Frequency (simple vibration) | X | X | ||
Buckling | X | |||
Pressure Vessel | X | X | ||
Drop Test | X | X | ||
Composite Materials | X | |||
Nonlinear | X | |||
Random Vibration | X | |||
Dynamic | X | |||
Rotating Machinery | X | |||
Heat Transfer & Cooling | X | |||
Flow (Internal & External) | X |
“There are three other simulation technologies,” explains Whyte. “Flow Simulation is a CFD tool used for fluid flow and heat transfer. It has some extensions for electronics, and the HVAC industry. We also have a simple first pass life cycle assessment tool to determine the environmental impact of the materials and manufacturing choices. Finally, we have a plastic injection molding tool to detect potential injection molding defects … Generally we don’t like to bundle things. Typically you want to be able to buy what you want.”
However, Whyte was quick to note that the other benefit is cost: “though only a sales team can give you a final quote, you can get SolidWorks Simulation at a fraction of the cost of other simulation tools.” This means companies can reduce the licenses of other costly heavy lifting simulation tools, which are far too advanced for designers anyway, and limiting those licenses to analysts and simulation engineers. This can ensure designers are able to perform simple simulations on a lower budget.
Conclusion
Again, SolidWorks Simulation isn’t the tool for complicated high level simulations. But that weakness has been turned into a strength. This barebones simulation tool will ensure that your designers and design engineers will pass on fewer partly optimized designs to analysts and simulation engineers.