As the automotive industry’s transition to electric propulsion continues to accelerate, automakers are looking for ways to make their cars more and more aerodynamic. And that has led to some fascinating and sometimes weird solutions.
Porsche recently admitted that the University of Stuttgart is conducting research into making an entire car vibrate, among the methods being tested to help vehicles cut through the air more efficiently.
“We are investigating whether it is possible to lower the Cd value at certain points in the car body by systematically introducing vibrations,” says Professor Andreas Wagner, chair of the automotive engineering program at the university. “If you apply a defined pulse to the flow around the car with loudspeakers, the separation behavior can be influenced.”
However, the method still presents some challenges and is still quite early in the development phase. Porsche would, as you would expect, want to make sure that the method does not affect the N and the V in NVH (noise, vibration and hardness) too much.
“For example, we need to make sure that passengers don’t hear any buzzing or buzzing,” Wagner says. “That still has a long way to go before serial production.”
The automaker is also working on ways to make its EVs more aero efficient that are closer to production. Active aero, for example, still has a lot of untapped potential to allow vehicles to move through the air with less drag. Simulation tools are constantly improving to help them on their way.
“Computational fluid dynamics simulations have become hugely important over the past 20 years,” Wagner says. “People have better understood the mathematical methods, developed more accurate tools and also increased the processing power of the computers.”
However, there is still room for improvement. For example, computers struggle to simulate the effects of rotating tires on the air, and their deformation under the weight of a vehicle is also very difficult to simulate accurately. Intelligent algorithms are now being developed to help, and artificial intelligence is expected to make a significant contribution to aerodynamics.
“AI algorithms can generate new data from a pool of existing data through interpolation and extrapolation,” said Dr. Thomas Wiegand, aerodynamics R&D manager at Porsche. “This would allow us to plan specific experiments and reduce their number. And we would no longer have to measure all variants for classification.”
That research does not mean that all EVs will look the same. Porsche’s research can help the company get better at making efficient vehicles, giving designers more freedom, not less.
“A good CD value can be achieved in several ways. For example, if you want to optimize the rear, you can change the height of the tailgate and the diffuser in the bottom,” says Marcel Straub, chief engineer aerodynamics and thermal management at Porsche Engineering. “There is no risk of one car being mistaken for another, not even the best vehicles in terms of aerodynamics.”
