[LMP]

Do you think aerodynamics affect slot cars enough to be significant?

I was just thinking since the cars do more than scale speed, there might be enough force to make a difference.

 

[James - Junior Racer]

A friend of mine who works for Rolls-Royce also asked this question. He tried wind testing on a Scalex Porsche GT1 that his son races at Pendle. His results showed there was a difference, but it was minimal. This may be because of the car that he used.

I would say that it does, if you glue 2 spoilers on a normal GT car (stacked up), you'll notice the difference. I felt it did.
A Good question Gary

Jimbo

 

[Mo55man]

Unfortunately though, you cannot scale down air. I know the so called Parma wing cars that are used, which are just a scaled down wing basically, must take some benefit from downforce.

M

 

[LMP]

I'm going to try some experiments with some modable plastic, I'll let you know how I get on.

 

[GRAH1]

Aero dynamics certainly have an effect on slot cars on faster tracks a 1/24 flexy car can easily exeed 40 mph and a brsca strap car can top 60 on a suitable track ,choice of body can make a big difference to the way a slot car performs.
However on scalex track where the speeds are lower aerodynamics dont have much affect if any.

 

[RichD]

I have seen 1/24th cars suffer from "aero push" on commercial raceways. You had to be very careful if you were following another car into a tight corner at high speeds.

 

[Harry Porsche]

Yes, the cars are moving through the air, so there is some resistance as speed increases. The air , however, as mentioned above is a constant in the equation. Relative to the car, the air density is much less, so the resistance is proportionately lower as the car is 32 times smaller than the full size car. The 1/32 cars would need to move very much faster than they usually do to be affected by the relatively (to them) low air density. Tire friction and weight, as well as mechanical drag in the car are much more measurable and affectable than the aerodynamic forces a 1/32 car experiences. We just don't go fast enough for it to matter.

 

[howmet tx]

Hi Harry- you're doing a good job of protecting us all from the Turnmarshall. Relieved that you are back and with mental capacities undiminished.
Not so much as a sniff from the Turnmarshall though. You must have got him good.

 

[Tropi]

Just a little mathematical addendum.

Our scale is one dimensional only at 1/32
For area, it is actually 1/32 of 1/32 = 1/1024
For volume, is 1/32 of 1/32 of 1/32 = 1/32768
As volume determines mass, via density, 1/32768 applies to mass also.

Multi-dimensional thinking tends to confuse the issue though.
Hence, despite Spanish origins, people like Dali and Picasso were not big in slot cars!

The net result, in connection with the original post, is that, all other things being equal, the aero effect is reduced by around 1024 times when applied to a 1/32 scale car compared with its full-size brother. ie not a lot!

 

[Fergy]

I agree. For 1/32 scale-type cars, on typical non-commercial tracks, the aerodynamics involved are too small to be measured or noticed simply because the car does not travel fast enough. The addition or alteration of aero devices may have an effect, but this is no doubt due to changes in weight and/or weight distribution, rather than actual aerodynamics. When you get into "wing cars" on commercial tracks, then yes, aero becomes a factor simply because of the speeds involved, but even then note that they don't use sophisticated, engineered aero devices (proper wings, for example, on a slot car are just too small to be effective). Rather, they employ a "brute force" method of utilizing aerodynamics by placing a large surface in the air stream that generates as much drag as it does downforce. Crude, from an aerodynamicist's viewpoint I'm sure, but quite effective at high speed.

Now.... shall we get into boundary layers, flow separation, vortices....

...let's not, my head hurts when I do!

 

[Tropi]

Fergy - here's an aspirin.

Now get stuck in there!

 

[Harry Porsche]

Yes, Howmet, I did make it back, thank you. The Turnmarshall may well have been sent back to his lair with the loss of a major stronghold. Took two weeks to dig myself out of the rubble! It wasn't just myself doing battle though. Without the heroism of Dick Winkin coming out of nowhere with an antique Scaley F1, the damage might have been far greater. I was glad to cede the track record to him at 4.035 sec./lap for the security of all here at the Slot Forum. The turnmarshall was raging with this latest blow to his ambitions on our universe. The earth was heaving great molten masses skyward as he descended back into the place he rises from. The shaking of his head was a blur as the he darkened the sky. This glorious victory will be short-lived I fear as the Turnmarshall has gained more knowledge and tasted a bit of the Blood of Doom. The Guardians of Doom are quiet now. They are the best early-warning of the Turnmarshall's approach into our world. I will be keeping watch over them.

He's gone, so heres to nothing but fun!!

 

[howmet tx]

Ok, got that, Harry. Thanks. All makes perfect sense. I shall sleep easily tonight.
Now about those boundary layer effects, Ferg...