Golf ball aerodynamics in F1

[slimjim8201]

I think the shoddy paint job is more a function of thin paint for weight-savings than to expose a certain weave texture. Every Ferrari on display in Maranello has a shitty paint job from what I could tell. Just enough paint to be red.

On surfaces where one is not trying to prolong separation for wake minimization considerations, for instance the large generally flat surfaces of the side pods shown here, the desire would be glassy smoothness. That said, I doubt the low-level roughness from the carbon weave has much impact on skin friction.

[jordangp]

From what I've heard the golf ball's effect is produced due to the rotating of the ball, and according to some fans' tweets on a BBC F1 Practice session some time ago now, I recall someone saying, it would not have the same effect on the car, because the surface is not rotating

[RacingManiac]

To make your painted surface, especially like the weave carbon surface completely smooth, you'd have the fill the surface with bondo and sand it flat, which is heavy....I doubt they do that for F1...

In some cases also the surface may not be painted....a lot of the race car now go with full vinyl wrapping(ie, Peugeot 908)...

Random addendum to the original topic...anyone caught a Mythbuster ep on the golf ball car from a couple of years ago?

[hollus]

firstly i Apologize for not reading through the entire thread before posting this, but i have thought about this for a while now,.. and think Ferrari and RB are already using a similar technique (golf ball) aero, maybe a larger carbon fiber weave,? to create the bumps? I have not seen it on any other cars, and it differs form track to track, no all tracks have this "golf ball paint" some tracks are smooth

also on Ferrari photo, people have commented on poor painting technique, but if you look closely you can see the weave (highly doubt its a shoddy paint job, on a car that has millions invested in it,.. all other cars are smooth.

Rb = on side pods and engine cover

Any thoughts ?

My thought would be that if you could not read through all of 2 pages of this thread, it might get a bit difficult to have an intelligent discussion...

Anyways, golf ball dimples are there to help with the aerodynamics of an object that is not aerodynamic at all. Bodywork surfaces in F1 cars are highly optimized, and the holy grail is laminar flow except where one wants something like a vortex or in necessarily messy areas, like the tires where other principles trump shape.
Flat surfaces are the optimum shape for both low drag and, if wanted, lift, just about anywhere where the airflow is orderly. Road cars have them, light weight slow gliding aircraft have them, high speed trains have them, planes have them, land speed record cars have them and even bullets have them.

[machin]

Noticed a few of these on this year's Tour De France in the individual time trial at the weekend:-

Dimples on the front surface of a Time trial cyclists otherwise fairly stream-lined ("tear-drop" shaped) helmet:-



[edit] Its not intended to rotate...

[MIKEY_!]

This is what i said earlier, dimples help airflow to stick to a surface that it would otherwise break away from, preventing massive drag.

Particularly useful on very tight or angular sidepods or on wings with large angles of attack. The risk is this turbulent flow in the diagram. If a surface is less tight than the golf ball pictured there will be less turbulent flow.

[Greg Locock]

Dimples were also used on the door mirrors of cheap BMWs a while back. I suspect they were there to either (a) look techy or (B) prevent separation to reduce windnoise.

If you buy me a cheap BMW I will experiment further.

[allstaruk08]

i thought the dimples only came into effect when the ball was spinning? a few years ago i got ripped to pieces for suggesting to dimple the leading edge of the sidepods, people saying that it only works when the ball spins

[Greg Locock]

Well you can tell whoever ripped into you that using sharp edged features to trip the flow is standard practice in some fields, on normal wings.

[olefud]

This is what i said earlier, dimples help airflow to stick to a surface that it would otherwise break away from, preventing massive drag.

Particularly useful on very tight or angular sidepods or on wings with large angles of attack. The risk is this turbulent flow in the diagram. If a surface is less tight than the golf ball pictured there will be less turbulent flow.

My impression is that the golf ball dimples induce a turbulent boundary layer that attaches the slipstream to the ball better than a laminar boundary layer. The resulting later separation decreases drag.

Also, with the back-spinning spinning ball also traveling through the air, the peripheral surface velocity of the ball relative to the air is greater at the bottom of the ball than the top. This “piles up” air under the ball and thins the air at the top to generate lift. The dimples amplify this effect by increasing the boundary layer thickness.

[Nando]

I was under the impression dimples in gold balls creates air pockets.
Air pockets that interact with the air and not the gold ball, therefore the drag is virtually non-existent.

[Greg Locock]

-1 Nando.

The explanation I have read is that the dimples energise the boundary layer, and that this causes the general flow around the surface to separate later than with an untripped flow. The rotation of the golf ball is a separate affair, and creates lift on the ball due to the coanda effect. A dimpled golf ball has a stronger coanda effect because it has a longer attached region for the airflow.

[olefud]

-1 Nando.

The explanation I have read is that the dimples energise the boundary layer, and that this causes the general flow around the surface to separate later than with an untripped flow. The rotation of the golf ball is a separate affair, and creates lift on the ball due to the coanda effect. A dimpled golf ball has a stronger coanda effect because it has a longer attached region for the airflow.

"Energize" is a bit collooquial, but turbulance does have more energy. The dimples attach a thicker boundary layer but without rotation do not provide lift. With rotation it's called the Magnus effect.

On a true aero surface sometines a thicker or turbulent boundary layer is helpful, but often not. Dimples (surface roughness) is more a tool than an answer.

[coaster]

I saw a filled port on a cbr600, the floor was filled and raised and dimples were added to the floor, d ported.

[Cocles]

Why not simply try this out on the axle rods?