Why are cars not dimpled?

A smooth golf ball tends to have that smooth kind of boundary layer which gives high drag. For a car or train, which are quite fast and very large compared to a golf ball, the boundary layer is turbulent anyway so dimples have no effect.

Would a car with dimples be more aerodynamic?

In short, the dimples help delay the airflow separation from the ball and create a smaller wake of air behind, so there’s less drag.

Do dimples on a golf ball reduce drag?

Dimples on a golf ball create a thin turbulent boundary layer of air that clings to the ball’s surface. A dimpled ball thus has about half the drag of a smooth ball. Dimples also affect lift. A smooth ball with backspin creates lift by warping the airflow such that the ball acts like an airplane’s wing.

Does adding dimples to a car increase the gas mileage?

On a recent episode of the TV show MythBusters, special effects experts Adam Savage and Jamie Hyneman ran tests to see if a dirty car is more fuel efficient than a clean one. It turned out that dirt doesn’t make a difference to the mileage (in fact it reduced mileage by ~1.5 mpg).

Why are aircraft f1 nose cone reluctant to install dimples in their wings body?

Dimples aren’t used because wings are already streamlined. Dimples aren’t used because wings are already streamlined. However, actually there is something similar to dimples that are used on some airplane wings called vortex generators.

What is the conclusion in the dimple car experiment?

We discuss how an increase in surface roughness of a streamlined body leads to an increase in drag. Since most recently built cars are stream-lined, it was concluded that introducing dimples on a car would lead to an increase in drag.

Do dimples on Zipp wheels work?

The dimpled wheels showed very good Reynolds numbers, especially when compared to similar, non-dimpled versions. On Zipp’s smooth discs this was much higher than for the dimpled wheels and, suggesting the Recr is reduced by the presence of the dimples.

Why are golf ball dimples different sizes?

The dimples work to break the air around the ball in flight, and have two key characteristics that are measured: Lift and Drag. The ideal dimple design is a combination balancing the lift and drag of the ball. We vary the diameters, shapes, total coverage, edge angles to control these two key variables.

Did golf ball get better gas mileage?

Yes. Apparently, covering your car in clay and dimpling it like a golf ball will result in a significant increase in gas mileage.

How much does a flat floor reduce drag?

As high velocity typically equals low pressure, this means we end up with a higher pressure on the total underbody (lift). By adding the flat floor we dropped our drag force at 180km/h by 15kg, and our downforce increased by 50kg.

What is the dependent variable of the dimple car experiment?

The dependent variable — what we measure as the effect of the car’s profile — could be speed, gas mileage or a direct measure of the amount of air pressure exerted on the car.

Do aircraft with dimples on the surface reduce drag?

Dimpling aircraft surfaces will not reduce drag because the airflow does not separate (under normal conditions) from the surface like it does on the back of a flying golf ball. The dimples minimize the airflow separation.

Why don’t cars have dimples like a golf ball?

The dimples in a golf ball will make this layer resemble that of larger objects and help to make the flow resemble that around larger objects like a car by reducing the area of separated flow at the rear of the object. A car is large enough so it doesn’t profit from dimples the way a golf ball does.

Why do airfoils have dimples in their shape?

In airfoil shape case, the friction drag is about 90\% of the total drag due to already optimized form drag. Adding dimples on such shape will only increase the total drag. Aircraft already utilize a different means to induce turbulent flow within the boundary layer.

Do dimples on the surface of a smooth sphere reduce drag?

About 90\% of the drag of a smooth sphere shape is pressure drag and the rest is friction drag. Putting dimples on surface will increase the friction drag but will reduce the pressure drag by having the turbulent boundary layer attached farther before separation.