What’s new for GM Racing? Well, aside from manufacturing auto parts like GM tail light guards for their race cars, GM also got something new for the motor sports industry. The 2007 season of the NASCAR Nextel Cup Series is an important event for GM Racing team for them to unveil a brand new racing machine and an all-new engine. GM will make the NASCAR debut of the Chevrolet Impala SS “Car of Tomorrow” along with R07 small-block V-8 racing engine. Along with the debut of the Chevrolet Impala SS, GM also announced their latest development in testing vehicle aerodynamics called the Computational Fluid Dynamics (CFD) that will be implemented in all GM race cars.
Here is how Kevin Bayless, GM Racing oval track chassis/aero Program Manager explains how the CFD works:
“The best way to describe CFD is a wind tunnel in a computer. CFD is a simulation that predicts the aerodynamic forces acting on a vehicle using computational methods rather than physical measurements. CFD allows engineers and racing teams to evaluate the effects of aerodynamic changes quickly on a computer screen rather than in a conventional wind tunnel.
The CFD software requires a supercomputer because the number of calculations is immense. For example, our aerodynamic models typically have more than 10 million discrete data points that are used to calculate the forces. It really is rocket science.”
“CFD allows us to visualize the flow to understand what the air is doing and where the aerodynamic forces are being generated. That’s simply not possible with a model or a full-size vehicle in a wind tunnel. CFD also allows us to test aerodynamics without a physical model, which can be helpful in the early stages of a design. We can analyze and compare various alternatives before actually building a prototype vehicle.” he further explains.
GM Racing will first implement the CFD aerodynamic simulation system to the next-generation Chevrolet Impala SS that will debut in NASCAR Nextel Cup Series. GM said engineers utilized the CFD to gain insight into the effects of the new body shape, front splitter, and adjustable rear wing of the Impala SS. However, GM said although CFD is a powerful engineering tool for testing vehicle aerodynamics, it is not a replacement for the typical wind tunnel and track testing.
Bayless commented: “Although the Car of Tomorrow is highly regulated, it’s not a spec race car. As a manufacturer, Chevrolet was able to define many of the details that separate the Impala SS from our competitors’ cars. The headlights, grille, portions of the hood, and the tail were areas where GM Racing was able to incorporate Impala SS styling cues and brand identity. These areas are now fixed as part of the NASCAR Impala SS package.”
“The computing time required to run CFD programs is a limitation even with a supercomputer,” Bayless noted. “A team can run through more tests in a day in a wind tunnel than can be done with CFD. At this point in its development, CFD supplements the testing that’s done in wind tunnels and on race tracks. We share the information that GM Racing obtains through CFD with the Chevy teams.” he added.
Just wait and see how the Chevrolet Impala SS “Car of Tomorrow” performs at the NASCAR Nextel Cup Series this season.