331 replies to this topic

[saudoso]

This comes from another thread, but I think it deseves one of it's own...

Originally posted by McGuire



With little tires on the front and big tires on the back, a vehicle will travel faster as it is in effect perpetually running downhill. If you measure the rpm of the front and rear wheels at any given speed with this configuration, you will find that the front wheels are turning considerably faster than the rear wheels. There you have it: irrefutable proof that the front wheels are actually pulling the vehicle down the road. This was the real speed secret of the Tyrell P34, which employed not one but TWO sets of dinky front wheels for maximum thrust. This did not double the available thrust as is often claimed, due to an unfortunate Magnus effect on the second wheel pair. But the total thrust was increased considerably over conventional four-wheeled cars. However, the car was banned by the FIA and a consortium of petroleum interests before it could be developed for passenger car use.

I've heard from a good source that there is a rule, wich is in that Blue Book* everyone have heard off, that says cars cannot be painted black in the forward half and white in the back one. This is because when the sun hits the car, the forward half goes hotter, therefore heating the air and producing a low pressure area, that pulls the car forward.

* The "Blue Book" keeps the rules we are not allowed to know. Those rules protect the dark interests of sponsors, governmet agencies and alliens that are involved with motorspots.

[xflow7]

Please tell me this is a joke.

[Keith Young]

What?

[Keith Young]

I'm sorry, what?

[kilcoo316]

Uhm I think this is what would really happen (but i could be wrong)

A forward rotating "free" wheel will produce a downforce, i.e. no interfering ground plane - classic magnus, but in the real world the physics may change and there is lift produced by the stagnation point caused by the ground plane.

[Antti]

Saudoso and McGuire,

Your profound understanding of Magnus effect is rare to see and I am amazed at your grasp of the situation. Added to that your daring in revealing the long hidden secrets of BE-Aliens conspiracy speaks volumes of your courage in the face of the perhaps greatest threat to mankind. But you have crossed the limit when you have mentioned the notorious "Blue Book". Rest assured the conspiracy will not let this pass and your days will be numbered.

In humble remembrance of the most insightfull and courageous members of this BB

Antti

[Keith Young]

I cant think of a word.

[Schummy]

Was not "McGuire" a character from M.A.S.H.?

It would explain...

[red300zx99]

I'd like to hear more

[12.9:1]

Then We'd have to kill you

[Halfwitt]

The Magnus effect is little known and, still further, little information can be found about it. You see it isn't in the interests of the petroleum companies to have this effect exploited, as it has obvious implications for their businesses which, as you all know, basically control the planet to a greater or lesser extent. They (the oil companies) have people that trawl the net finding sites that publish information and dat on the effect, and then wither shut down or buy the site and put it out of business. Much the same happens to publishers and authors. Offers are made that can't be refused and the data never gets to the public domain.

Sometimes, if you are lucky a search on google for example will reveal something. If it does, print the data, because it is likely it will be found and then will be gone within hours.

For those of you well versed in physics and maths (lots of differential equations and calculus here) the effect can be explored by going back to first principles and working the maths through

However, because the effect essentially conserves energy, do not attempt to work the maths using a car on a downhill run. Otherwise one of your boundary conditions is in effect infinite, and attempts to run it on a computer will cause it to lock, which is a pain. During Tyrell's days with the six wheeler (ever more complicated) they used slide rules, which have a lower tendency to lock with infinite quantity calculations.

This is a quite remarkable field of study. Don't start publishing results though on Atlas, else Atlas will disappear. You've been warned.

[Deepak]

search for magnus effect found me a lot of links but none to explain its effect on formula 1. But its seems like it explains the reasons for curve balls in baseball and swing in cricket balls.

[McGuire]

Have you ever written a post, hit the "submit reply" button, and then immediately and forever after wished you hadn't?

[red300zx99]

So does anyone feel like doing alittle math?

I've been warned...........oh well, never been good at listening to rules

[Halfwitt]

I'm afraid a little math won't solve this one.

It's a problem which will take some solving to get a workable solution. When I looked into it a long time ago, I found that the best (easiest) case was to work out which uphill gradient would need no tractive effort to maintain steady velocity motion. This is a simple trig operation based on the size of the wheels and the wheel base of the car. Work on a frictionless model at first and see how you go.

Good luck red300zx99...... you could be away for some time

[dosco]

Originally posted by McGuire
Have you ever written a post, hit the "submit reply" button, and then immediately and forever after wished you hadn't?

But it's sooooooo funny.

Bwahahahahahaha.....

[Viss1]

What would happen, though, if a Magnus effect car was painted black in the REARward half? Would the considerable pressure differential cancel out the Magnus effect? And might this be the cause of Minardi's moderate pace?

[hydra]

I don't mean to be a partypooper, but this thread is both useless and ********... Definitely not TF material, so could one of the admins please please lock it, delete it, or at least banish it to the RC forum???

[desmo]

I'm tempted to believe me, but what's to say we can't have a bit of silly fun from time to time?

[Vrba]

The car is in effect going downhill if the front tyres are smaller?!?
Hm, hm....

Hrvoje

[pabs]

LOL!!! I needed a good comic relief today.

[saudoso]

Originally posted by McGuire
Have you ever written a post, hit the "submit reply" button, and then immediately and forever after wished you hadn't?

sorry for that

Could someone please come up with new theories?

[saudoso]

Originally posted by hydra
I don't mean to be a partypooper, but this thread is both useless and ********... Definitely not TF material, so could one of the admins please please lock it, delete it, or at least banish it to the RC forum???

All work and no play makes Jack a dull boy

Sorry if I hurted feelings here.

BTW, some source of inspiration: http://www.xs4all.nl...verha/scijokes/

[Halfwitt]

Originally posted by hydra
I don't mean to be a partypooper, but this thread is both useless and ********...

Oh you are so nice!!!! Nobody has ever called me a thread before

[Deepak]

Originally posted by McGuire
Have you ever written a post, hit the "submit reply" button, and then immediately and forever after wished you hadn't?

now... was that directed at me?!

[Yelnats]

Originally posted by Vrba
The car is in effect going downhill if the front tyres are smaller?!?
Hm, hm....

Hrvoje

Vrba, I'm afraid to disappoint you in the midst of your cogitations but the only thing going downhill here is this thread!

A little historical perspective is required here.

For centuries the "big wheel rolling down hill" theory was accepted and the results can be seen in horse drawn carriage where almost invariably the rear wheels were larger. Some hilly countries even resorted in the sophisticated technique of reversing the wheels when traveling down-hill (the big ones at the front) to reduce the loading on the horses and crude brakes of the time.

The rail vehicles of the early 19th century saw the first cracks in this theory develop when it was expected that, due to the insignificant friction of iron wheels on iron rails, a large rear wheeled train would at least make some effort to move of it's own accord. Of course this proved false and since those times this theory has disapeared from transportation theory completely.

This is why I am so disapointed to see this old and thorougly discredited theory re-emerge before such a well informed audience and garner such a credulous response.

Shame on us!








;)

[McGuire]

Watching engineers and associated technical geeks such as ourselves attempt humor is sad and a bit touching...rather what it must have been like watching aborigines on a south pacific island reverently attempting to replicate a B-17. Some pieces of bamboo lashed together provide a rough verisimilitude, but we know the actual principles are beyond their comprehension and it will never fly.

[Vrba]

Originally posted by Yelnats

....
This is why I am so disapointed to see this old and thorougly discredited theory re-emerge before such a well informed audience and garner such a credulous response.
....

Yes.
Who on Earth could have come up with such a theory?!? I like this part the best: "If you measure the rpm of the front and rear wheels at any given speed with this configuration, you will find that the front wheels are turning considerably faster than the rear wheels. There you have it: irrefutable proof that the front wheels are actually pulling the vehicle down the road."
One of most senseless things I've seen recently....

H

[hydra]

[Peter Perfect]

Is that why penny farthing bikes are hard to ride? Because you're always peddling uphill?

[Scoots]

I like bannanas because the have no bones.

[Blue]

I made modification to RC-car using The Magnus effect. Unfortunately when the batteries run out the car kept accelerating and finally the speed was so high that I lost control The car hit the tree and broke for thousands of pieces.

Surprisingly I could not make it work again, it has to do something with the tyre compound I used. In first model I used old tyres and now I can’t find exactly same kind from anywhere.

[Keith Young]

Maybe the "throttle" stuck.

wouldnt magnus make braking worse, or could the teams have changing color paint and use hydraulics so the car is going uphil? At euo rouge would the car remain still in nuetral if using this theory?

[onepablo]

Despite my more democratic inclinations, I suggest that all posters in the TF include a disclaimer whenever they post on a subject outside their expertise. Of course, that means I will never post ere again.

[alexbiker]

Originally posted by McGuire
Watching engineers and associated technical geeks such as ourselves attempt humor is sad and a bit touching...rather what it must have been like watching aborigines on a south pacific island reverently attempting to replicate a B-17. Some pieces of bamboo lashed together provide a rough verisimilitude, but we know the actual principles are beyond their comprehension and it will never fly.

Oooh, get her.

I have duplicated the Magnus effect by wearing one stilletto and one sandal. By sidestepping, I manged an 8.91 for the 100M. However, after the unfortunate incident with the crashbarrier, pretty water bottle girl and nine hours in A&E (the ER for the colonials), I am hurredly designing a quick release mechanism for the stiletto, thereby providing an uphill slowing down slope.

After stopping, I will hurredly discard the sandal. Otherwise, I will meet some slower competitors coming the other way. This would be bad.

Alex

[DOHC]

Originally posted by Yelnats
due to the insignificant friction of iron wheels on iron rails

Not a contribution to the jokes, but a comment on friction:

Steel on steel has a rather significant friction. Dry friction coefficients are on the order of 0.4 -- 0.8 depending on how hard the steel is, and whether it's static or slipping conditions. That's not small at all.

The "myth" of the insignificant friction in the steel wheel -- steel rail contact comes from the rolling resistance in dry friction conditions. This friction coefficient is of the order of 0.001 and can rightly be considered insignificant.

But if that was the dry friction coefficient in steel -- steel contact, then a train wouldn't be able to brake, it wouldn't be able to get going, and Switzerland wouldn't have any trains at all. Even the slightest incline at a station would see the train slip away downhill...

[StephenJK]

Further to the comments on friction, as relates to trains, in colder climates the locomotive is fitted with sand boxes. The sand can be released by the Engineer directly at the driving wheels to generate additional tractive effort.

The part I don't understand, and have yet to verify and/or hear a good explanation, is tests conducted by some railroads where, it was supposedly discovered that better forward progress could be made if the locomotive wheels were allowed to spin in a controlled fashion. That would seem to be counter-productive, so if anyone has an answer I would definitely be interested in hearing it.

[Yelnats]

Originally posted by McGuire
Watching engineers and associated technical geeks such as ourselves attempt humor is sad and a bit touching...rather what it must have been like watching aborigines on a south pacific island reverently attempting to replicate a B-17. Some pieces of bamboo lashed together provide a rough verisimilitude, but we know the actual principles are beyond their comprehension and it will never fly.

Duhhh.. Well excuse us!

The humour may be bad but the responses are sometimes hilarious.

[McGuire]

Originally posted by DOHC


Not a contribution to the jokes, but a comment on friction:

Steel on steel has a rather significant friction. Dry friction coefficients are on the order of 0.4 -- 0.8 depending on how hard the steel is, and whether it's static or slipping conditions. That's not small at all.

Well there's that, plus trains weigh A LOT.

[McGuire]

Originally posted by Yelnats


Duhhh.. Well excuse us!

Come on, own it. You know that behind their monitors, this forum consists of several dozen people wearing short-sleeve dress shirts, pocket protectors, and white socks. Probably carry their HP's in belt holsters...which would probably look cool, except the trousers are worn up around the rib cage. Celebrate your tribe.

[McGuire]

Originally posted by Deepak


now... was that directed at me?!

Not at all. My post, my everlasting regret.

[Yelnats]

Originally posted by DOHC


Not a contribution to the jokes, but a comment on friction:

Steel on steel has a rather significant friction. Dry friction coefficients are on the order of 0.4 -- 0.8 depending on how hard the steel is, and whether it's static or slipping conditions. That's not small at all.

The "myth" of the insignificant friction in the steel wheel -- steel rail contact comes from the rolling resistance in dry friction conditions. This friction coefficient is of the order of 0.001 and can rightly be considered insignificant.

But if that was the dry friction coefficient in steel -- steel contact, then a train wouldn't be able to brake, it wouldn't be able to get going, and Switzerland wouldn't have any trains at all. Even the slightest incline at a station would see the train slip away downhill...

Pardon me for not including the term "rolling" in my post but I thought it was obvious from it's context which was entirely about rolling stock.

[Yelnats]

Originally posted by McGuire



Come on, own it. You know that behind their monitors, this forum consists of several dozen people wearing short-sleeve dress shirts, pocket protectors, and white socks. Probably carry their HP's in belt holsters...which would probably look cool, except the trousers are worn up around the rib cage. Celebrate your tribe.

Actually I have a pony-tail, no shoes and am smokeing a dube. But I think you've got the rest of them right!

[McGuire]

Originally posted by Yelnats


Actually I have a pony-tail, no shoes and am smokeing a dube. But I think you've got the rest of them right!

Actually, I have felt guilty about my comment ever since I posted it...advancing as it does an unfair stereotype of engineering types. It was a cheap shot. If what I was saying were true, one could walk right into any manufacturing company and locate the engineeering deptartment just by noting the highest concentration of clip-on neckties. Which as we know is totally false.

[Paolo]

I wondered if anyone noticed Hydra is obviously an evil Oil company agent.
Oops... maybe those who noticed and said it disappeared and had their posts deleted...

Then, I'm a brave guy and will face my fate.
My last words of wisdom are for SthepenJk : all forward thrust from wheels comes from some degree of slip. Since there is an optimum, slipping can be controlled by a sensor.
It's called antispin , AFAIK.
One day we'll see this in F1, for sure...

Originally posted by StephenJK
, it was supposedly discovered that better forward progress could be made if the locomotive wheels were allowed to spin in a controlled fashion. That would seem to be counter-productive, so if anyone has an answer I would definitely be interested in hearing it.

[hydra]

Wow Paolo I'm impressed... It took you all of 2 weeks to come up with that?

Friendly word of advice; stick to engineering... because you'd make a pretty crappy comedian ;)

[Paolo]

Hydra, that's the tragedy of being beautiful : I never needed to develop a sense of humour.
Women were raining anyway...

[Psychoman]

Originally posted by McGuire


Actually, I have felt guilty about my comment ever since I posted it...advancing as it does an unfair stereotype of engineering types. It was a cheap shot. If what I was saying were true, one could walk right into any manufacturing company and locate the engineeering deptartment just by noting the highest concentration of clip-on neckties. Which as we know is totally false.

You forgot stapler addictions
(NOTE--the above link repeats over and over, feel free to close it when it gets annoying)

[ScottL]

Originally posted by McGuire


Probably carry their HP's in belt holsters...which would probably look cool, except the trousers are worn up around the rib cage. Celebrate your tribe.

When you pull your trousers up so that the beltline is just below the nipples, it's really a major styling faux pas to wear a holster. One must wear a bandolier in this case. Loaded up with electronic devices, the look is quite stunning, especially without a shirt.

[Christiaan]

No slagging on our BB please

WRT the black and white car, Ferrari ran a completely black nose in the USGP in 2001