TECHNOLOGY – COMPUTATIONAL FLUID DYNAMICS
Power tool How state-of-the-art software is revolutionising engine tuning By NICK BAILEY
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hen an engine specialist as experienced as Brian Kurn is excited about a technology, others in the field tend to take notice. If they don’t, they should. Kurn is currently working at ECR Engines, a division of Richard Childress Racing and is in charge of valvetrain development together with all virtual prototyping technologies, including engine and valvetrain simulation, as well as computational fluid dynamics (CFD). In a career spanning 25 years he has worked for some of the biggest names in the sport, including Roush, Hendrick and Bill Davis Racing. Kurn started his craft building and improving V8 engines for the small dirt tracks
and worked his way up to the elite series in NASCAR. He was highly-regarded for his work on cylinder heads and his ability to extract more power while retaining reliability. Today, he’s a highly-respected engine developer who has plied his trade, successfully, across many racing championships – Tudor United Sportscar Championship, NHRA Pro Stock, American Le Mans Series (ALMS), Touring Cars in Brazil and Argentina, Truck-pulling, Supercross and, of course, NASCAR. ‘In the good old days, so-called tuners determined the biggest valves that could be used and then they simply began to hand-port the head, believing that the more air that would flow, the more power it should make,’ says Kurn.
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‘After spending a lot of time doing this, you took the parts to the dyno and only then did you find out if you had found a solution or just scrapped another cylinder head. It was an expensive and time-consuming way to see if your idea gained a few more horses or not. And each time you got a new head design, you really had to start again!’ It was this inefficiency which drove the forward-thinking Kurn to investigate simulation technologies. As an experienced CFD user, primarily to analyse internal flows in the engine, both standalone and coupled with engine simulation, Kurn is at home with state-of-the-art technology. But, in those early days just over a decade ago, CFD posed problems. ‘The run-times to do the