Case Study

The benefits of combining ANSYS simulation with HPC and cloud computing

PADT ANSYS Cloud

Simulation has become even more prevalent in the world of engineering than it was even 5 years ago. Commercial tools have gotten significantly easier to use, whether you are looking at tools embedded within CAD programs or the standalone flagship analysis tools. The driving force behind these changes are to ultimately let engineers and companies understand their design quicker and with more fidelity than before.

Engineering simulation is one of those cliché items where everyone says “We want more!” Engineers want to analyze bigger and more complex problems, as well as do large scale design of experiments with hundreds of design variations; all of that and they want these results instantaneously. They want to be able to quickly understand their designs along with common design trends, in order be able to make changes accordingly and get their products optimized and to market quicker.

ANSYS, Inc. spends a significant amount of R&D in helping customers achieve just that, and a large component of that development is High Performance Computing, or HPC. This technology allows engineers to solve their structural, fluid and/or electromagnetic analyses across multiple processors, and even across multiple computing machines. Engineers can leverage HPC on laptops, workstations, clusters and even full data centers.

PADT is fortunate to be working with Nimbix, a High Performance Computing Platform that allowed us to quickly and easily iterate through different models with various cores specified. It was seamless, easy to use, and FAST!

In order to get a better understanding of how Nimbix’s HPC platform helps to improve solve speed and efficiency, let’s take a look at four problems: a large tractor axle model, exhaust CFD model, rubber seal FEA, and a quadrocopter CFD model. These problems cover a nice spectrum of analysis size and complexity.

Tractor Axle FEA

ANSSY FEA

Summary

  • 58 Parts
  • 51 x Bolts with Pretension Gaskets
  • 928K Elements, 1.6M Nodes

ANSYS FEA cores

This model has several parts all with contact defined and has 51 bolts that have pretension defined. A very large but not overly complex FEA problem. As you can see from the results, even by utilizing 8 cores you can triple your analysis throughput for a work day. This leads to more designs being analyzed and validated which gives engineers the results they need quicker.

 

Exhaust CFD

Exhaust CFD

Summary

  • K-omega SST Turbulence
  • Multi-Domain
  • 33M Elements, 7M Nodes

K-omega SST Turbulence

The exhaust model is a huge model with 33 million elements with several complicated flow passages and turbulence. This is a model that would take over a week to run using 1 core but with HPC on a decent workstation you can get that down to 1 day. Leveraging more HPC hardware resources such as a cluster or using a cloud computing platform like Nimbix will see that drop to 3 hours. Imagine getting results that used to take over 1 week that now will only take a few hours. You’ll notice that this model scaled linearly up to 128 cores. In many CFD simulations the more hardware resources and HPC technology you throw at it, the faster it will run.

Rubber Seal FEA

Rubber seal FEA

Summary

  • 6 Parts
  • Mooney Rivlin Hyperelastic Material
  • Seal Leakage with Advancing Pressure Load
  • Frictional Contact
  • Large Deformation
  • 42K Elements, 58K Nodes

Rubber Seal FEA

 

The rubber seal is actually a relatively small size problem, but quite complex. Not only does it need full hyper-elastic material properties defined with large strain effects included, it also includes a leakage test. This will pressurize any exposed areas of the seal. This will of course cause some deformation which will lead to more leaked surfaces and so on. It basically because a pressure advancing solution. From the results, again you can see the number of models that can be analyzed in the same time frame is significantly more. This model was already under an hour, even with the large nonlinearity, and with HPC it was down to less than half an hour.

Quadrocopter Drone CFD

Quadrocopter Drone CFD

Summary

  • Multiple Rotating Domains
  • 2M Elements, 1.4 M Nodes

Quadrocopter Drone CFD

The drone model is a half symmetry model that includes 2 rotating domains to account for the propellers. This was ran as a steady state simulation using ANSYS Fluent. Simply utilizing 8 cores will let you solve 3 designs versus 1.

As seen from the results leveraging HPC technology such as Nimbix can be hugely advantageous. Many simulation tools out there do not fully leverage solving on multiple computing machines or even multiple cores. ANSYS does and the value is easily a given. HPC makes large complex simulation more practical as a part of the design process timeline. It allows for greater throughput of design investigations leading to better fidelity and more information to the engineer to develop an optimized part quicker.