Cutting Air Better

We see automobile bodies transforming. Futuristic designs that are sharper than Samurai swords. And as much as we might like them aesthetically, we have reached a point where they don’t just look crazy awesome but serve a technical purpose. And there’s only one technical department in the automobile industry that makes use of such designs, namely, Aerodynamics.

Why do Aerodynamics matter so much?

Its’ simple. When at high speed, try sticking your hand out of the window. If you keep your palm facing the wind with your fingers pointing upwards, you’ll struggle to keep it steady. Instead, if you point your fingers forward, it gets a lot easier. That’s just your hand, very small in size. Replace that with a bike or a car? Now it starts making a huge difference.

If you’d like to understand the basics of Aerodynamics, we’ve already covered an article earlier:

Breaking The Basics – Aerodynamics

If you’ve gone through our earlier article, we’ve discussed how vehicles are differently designed to improve Aerodynamic performance. Let’s discuss some ways to further improve Aerodynamics:

Most of the front body in a vehicle is taken up by Front Bumpers. Front bumpers are a complete piece covering the area below headlamps and centre intake grills. If a car crashes into a footpath, it’s the front bumper that gets damaged.

Dodge Charger Front Bumper
  1. Air dams

We might have seen thick rubbers stripes or fibre stripes fitted below bumpers making the overall front look lower. These are Air dams. They let less air pass through the under-body of the vehicle making it a low-pressure area. The top of the vehicle becomes a relatively high-pressure area. The high pressure increases down-force resulting in better traction.

Effect of Air Dam
Air Dam

2. Front Splitters/ Diffusers

These are thin and sharp looking structures protruding out of the bottom of the bumper. They are generally fitted at the lower end of air dams. As the name suggests, they split air coming from the front to the top and bottom of the vehicle efficiently.

Front Splitter & Hood Scoop

3. Hood Scoops:

Aerodynamically designed intakes are placed on bonnets to increase cooling efficiency, reduce air resistance or feed air to superchargers. We can see an example in the Dodge Challenger image above.

4. Roof Scoops:

These are inlets placed on roofs specifically in mid-engine/rear-engine cars for air intake, cooling and aerodynamic efficiency. We can see a McLaren 675LT in the image below with a Roof Scoop that feeds air to its engine in the rear.

Roof Scoop

5. Fenders

How air flows from the sides of a vehicle matters a great deal. The vehicle body around wheels is also designed to provide less air resistance and ensure smooth passage of air through the sides.


In the above image, see how the body around the wheel is smoothly protruding out? That’s the fender. They’ve also added a cut-out for air around the wheel to flow out to the sides.

6. Side-Skirts

Low pressure under the body is desirable. When travelling at high speeds, along with the top of the car being under high pressure, the sides of the vehicle are also facing high pressure. Naturally, high pressure gushes towards low pressure. We might have managed to create low pressure in the bottom of a vehicle by adding air dams and splitters in the front. There will still be high pressure air flowing from the sides towards the bottom. Side skirts are added to reduce this from happening. Side skirts bring the vehicle closer to the ground on the sides and help reduce high pressure air on the sides from going to the low-pressure under-body.

Side Skirts

7. Vortex generators

When air flows through any uneven surface, any minor deformity on the body, it starts twirling and forms a vortex. The image below shows the vortex formation of air through a canard. These are generally found on the front corners of cars curved upwards in shape. They increase downforce on the front.

Vortex through Canard

While winglets are fin like structures that can be found on the edges of splitters and side skirts. We can see this McLaren P1 having winglets in the side skirts and front splitter.

Winglets McLaren P1

We have already discussed about drag in our earlier article. The wake area causing increase in drag becomes an enemy to high speeds. Vortex generators are designed to distort the wake area by generating a turbulent air flow and as a result reducing drag.

Vortex Generators

The small fins shown in this image are vortex generators.

8. Rear Diffusers

They diffuse low-pressure air coming from the underbody such that it mixes with the high-pressure air from the top, again, to reduce wake area and drag.

As for spoilers, we’ve already covered them in our earlier article. We now know about most techniques used to make cars go faster at high speeds. We are blessed to be in a time where we’re seeing some of the best Automobile designs today. The next time you see a fancily designed vehicle, you’ll know the importance of its design.

With this we conclude our article and hope we further increased the depth of your Automobile and Motorsports Vision.

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