The testing will provide insight into how to improve cars efficiency by finding the optimum speed out of an electric car or reducing vehicle emissions output.
Testing Location: Catesby Tunnel
The testing took place at the East Midlands-based Catesby Tunnel – where the facilities helped test vehicle’s aerodynamics such as testing drag resistance in repeatable conditions. The first test focused on the drag of one of the University cars and looked at the difference in pressure distribution on the back of the car.
Pinpointing Performance Impact
Professor of Applied Aerodynamics, Duncan Walker says having access to the facilities at Catesby allows them to pinpoint what is having a negative impact on the car’s performance: “If we were to carry out these tests anywhere else, our results’ validity would be hampered by a series of external influences which are not in our control. Carrying out this work in Catesby’s converted railway tunnel allows us to gain more accurate results as the location allows for endless testing in repeatable conditions.
“Electric cars are becoming more and more common, and people are anxious about how far they can go on one charge. Aerodynamics plays a key role in that because if you reduce the drag, you can go further – so that’s where our interest lies in this first round of testing. Improving car efficiency can help us address these concerns.
This data will also help with those still driving petrol cars in the fact that understanding how to improve a vehicle’s aerodynamic performance can allow us to influence positive design changes to reduce the amount of fuel we burn or how much emissions we are kicking out when driving.”
Second Round of Testing with Laser Measurement Technology
The second testing round saw the researchers and laser measurement technology developer LaVision team up. They tested how a vehicle’s wake changes as its geometry is altered.
Senior Lecture in Applied Fluid Mechanics, Dr Daniel Butcher, says testing in this way is really unique: “Similar testing has been around for some years but how we are using the technology is what’s distinctive. We are seeing the vehicle pass through the light sheet where, typically, you’re in a wind tunnel where the vehicle is static and the air flows over it – so that’s the key difference and the benefit of having the facilities of Catesby available to us.
Another advantage of conducting these tests in this way comes in the form of being able to measure downstream of the moving vehicle – something that’s almost impossible to do if it’s static. It allows us to measure 10, 20, 30 car lengths after it’s passed through to ascertain what this means for when we’re on the road and around other vehicles.
Real-World Testing for Improving Car Efficiency
“These are real-world tests, testing the real aerodynamics around a real car in real and repeatable conditions. The whole test is really a development of the measurement technique but the data we gather here is going to help us validate our research and to better understand where the source of drag comes from. We can then share this information with vehicle manufacturers to allow them to build more efficient and aerodynamic cars. Improving car efficiency will benefit both electric and petrol vehicles in reducing drag and improving performance.”
