The field of automotive design and development is constantly evolving, embracing the latest technologies and best practices. This dynamic environment extends its influence beyond automotive into the realm of motorsport.
TotalSim, an Ohio-based computational fluid dynamics (CFD) consultant, is utilising technological advancements across industries, especially with respect to aerodynamics and racing.
‘Aerodynamics now plays a role from the top of the motorsports food chain with NASCAR and F1 down to grassroots racing,’ says TotalSim president Ray Leto.
‘There’s been an explosion of information in the past few years that’s allowed these technologies to not be exclusively for top level racing. This has enhanced not only the importance of doing aerodynamics, but the power of doing it well.’
Both physical testing on-track and wind tunnel testing are commonly used to analyse aerodynamics. While still recognising the importance of these techniques and incorporating them, TotalSim believes it has found the perfect recipe for quicker aerodynamic testing at a cheaper cost.
The magic ingredient? CFD. Computational fluid dynamics is a branch of fluid mechanics that employs numerical analysis to predict fluid flow digitally.
Advances in computing power have made CFD a valuable complement to physical testing and, in some instances, a replacement. CFD enables engineers to anticipate fluid flow, heat transfer, mass transfer, chemical reactions, and other flow characteristics by solving fluid flow equations.
The end result of CFD is data, specifically the data of ‘what could be.’ Digital modelling and simulation allow for the input of real-world variables or potential variables to create detailed maps of a vehicle. These maps are used to understand how the vehicle will perform under a multitude of scenarios and/or with various modifications.
This data is easily repeatable, for instance allowing a team to understand its car in unmatched ways and giving it the power to take what it already has and make optimisations.
This process is one of the main things that TotalSim’s co-founder, Naethan Eagles, will be diving deeper into during his seminar at the upcoming PRI Show in Indianapolis. He will focus on the ways in which digital wind tunnel testing can improve lap time while lowering research and development costs.
When he goes into the benefits of this testing, it’s important to recognise that it wasn’t long ago when this technology was too expensive for most. The breakdown of these financial barriers can be attributed in part to the proliferation of 3-D scanning technologies.
TotalSim uses 3-D scanning on a vehicle and reverse engineers it for aerodynamic testing and analysis. These technologies give TotalSim’s clients efficient and cost-effective results, according to Leto.
’15 to 20 years ago, there was a very small group of experts using this software effectively,’ he says.
‘What we have seen happen over the past decade, and actively have become part of, is the addition of automation around hard-to-navigate softwares. This makes it easier for the CFD simulations to reliably run in the background so that we can purely focus on aerodynamics.’
TotalSim employs software such as OpenFOAM and Star-CCM+, and tailors automated workflows. Commercial software like Star-CCM+ excels in speed and advanced physics processing, while open-source software like OpenFOAM offers flexibility without the need for added commercial licensing. It is a combination of open source, commercial and custom codes that really allow an aero design group to maximise the benefits of each software.
When you take a step back, it seems the real trick to getting the benefits of CFD is to take advantage of those who have already figured it out – and conveniently wrapped it in a pretty bow for you.
‘What we’ve done all started with trying to make our own lives easier by automating some of our own processes to make them run repeatedly and more efficiently,’ Leto says.
‘Then it became apparent that this automation is easy enough for non-experts to use, so we packaged our process behind a web interface in the form of TSAuto and other applications. The open source solvers are great for a reasonable set of cases where we’re looking at aerodynamics on a vehicle. But the commercial solvers are better for complicated physics, thermal analysis or applying other advanced techniques.’
Customers don’t have to choose one type of software or the other. TotalSim’s capabilities expertise is spread across many tools and can be easily personalised to fit specific client needs.
‘Racecar modelling is all about rapid turnaround, rapid analysis and consistent methodology to create results that you can reproduce on race day,’ Leto says.
‘We have a really great team of engineers here, a couple thousand computer cores along with a 10Gbit/s connection to the Ohio SuperComputer Center that are all working toward finding what is needed for a car and driver to succeed.’
Despite the obvious benefits of CFD, branching into this new territory can make one understandably uneasy. CFD isn’t something that can be easily picked up and learned on the fly.
That’s why, for most companies, especially within the small and medium-sized enterprise (SME) cohort, strategically partnering with a CFD consulting team makes the most sense.
In the ever-evolving world of motorsports, staying ahead of the competition involves getting the best value for your investment.
As you embark on your journey into simulation, don’t let uncertainty about where to start hold you back.
