How does the mclaren get its performance?

[zx4000]

Most of Mclaren enthusiasts are only concerned to chassis Nr., where are they, and who have this ultimate car..etc..about only appearance
and looking , not how their performance is obtained. for example, downforce package, ground effect and frame rigidity with impact stength. we already saw the Mclaren safety proportion through 30mph barrier test. There are only suspension and engien details in here.
I really wonder which parts is effected by the frame of mclaren f1(carbon fibre monocoque, honey comb) and how way is, except rigidity to weight ratio.
My focus is things related to the entire performance of mclaren.
I will appreciate for even a small things what you have info..

[Mr. Bernoulli]

Well if you have any specific questions, field them here and we'll see what we can come up with.

[zx4000]

Originally Posted by Mr. Bernoulli

Well if you have any specific questions, field them here and we'll see what we can come up with.

ok. The Mclaren F1 was developed to make more superior or near to
formula one by Ron dennis with Gordon Murray as not caring money.
But you know, actually formula one had problems in Ground effect.
To solve this ground effect + downforce(a little bit dangerous at high
speed ) generated by wings and noses,(because FIA prohibited use of Ground effect once again.)Gordon used powerful fan to solve this problem(positive)as trick in 1978.
Later on, this fan had contributed Mclaren F1 to get a avantage ground
effect as being altered into more advanced electric fan2.
so, My question is what electric fans is and how underneath of mclaren is designed to get ground effect.
Is there anybody who have more details about that?

[Porsche]

From what I gather you are partially asking how the fan works on the car?

It's somewhat simple, an eletric fan mounted somewhere in the rear of the car simply sucks out all the air from the distance of the body to the ground, which is usually just a few inches. This creates suction and keeps the car 'glued' at high speed. It works pretty decently, but all of this suction creates drag which in turn means less top speed.

As you pointed out, Murray originally came up with this years ago and the 'fan car' did quite well as I can recall when it competed.

I'm anot actually sure the F1 has a Fan system, in fact, I don't think it does, it just uses fancy aerodynamics on the underbody to channel air under the car and diffuse the pressure at the back with a small diffuser.

I'm sure Peloton can elaborate, I just wanted to feel half useful.

[Mr. Bernoulli]

Okay, let me have a go at explaining it before Peloton does it much better than me!

First of all, moveable aerodynamic devices in Formula 1 have been prohibited since 1969. The Brabham BT46B "Fan car" of 1978 was banned shortly after its introduction under this rule, having dominated its first race outing. In fact the team claimed the fan was primarily used for cooling and this wasn't far from the truth but like all good innovations in F1, if it makes you too good, it gets banned pretty quickly... Anywho, during the development of the F1 roadcar, Gordon Murray et al were free of such constraints and there was much oppotunity to think outside the box.

The rear fan was a combined solution to a double aerodynamic problem. The first is a classic problem of trying to get the airflow to stick to the surface to the surface of a body. In this case to the underside of the car. As the air travels under the F1 it is passes through narrowing channels which speed it up, lowering its pressure. As the pressure above the car is now relatively higher, it pushes the car down into the road. The problem they found during wind-tunnel testing however was that the flow was starting to detact from the underside of the car causing it to become turbulent. When it does this, aerodynamic benefit is lost and the car becomes unstable, especially under braking, as the car is pitched forward and so there is less weight over the rear wheels. The second problem was that they needed to get more air into the engine bay to cool the electrics and exhaust of the car. If they cut holes into the underside of the car, this would also ruin the aerodynamics.

The solution was a fan and an adjustable angle rear spoiler. During normal driving, the fan reduces the pressure on the undersurface so that the airflow adheres to the underbody of the car more readily, i.e. it sticks to the car better. This means the pressure pushing the car to the road is more constant over the whole car's length, rather than just the front of the car. A spoiler is usually employed to reduce lift at the back of cars -think Porsche 911 - as their shape can make them actually act like aircraft wings and produce lift. In some cases - eg Audi TT - this lift can cause the back of the car to become dangerously light.. Unfortunately a spoiler (hence the name) will cause huge drag as it is designed to spoil and cause separation of the airflow. The solution is a spoiler that only operates when it is needed (ie under braking). The spoiler on the F1 has one other trick up it's sleeve though. When it operates, the action of it popping up causes extra channels to open up from the fan. This increases the effectiveness of the fan and so the rear of the car is force down into the road further by external pressure on the roof of the car.

Hope this explains what you were after zx4000. If you have any problems with my rather long-winded explanation please post and I will try and expain myself better.

[Peloton25]

I'm quite certain when it comes to technical engineering questions that you are much better equipped to answer those than I am. Unless the answer can be found in bold type somewhere else, then that kind of stuff is usually over my head.

I do have an image that partially explains what Mr. B has described:



Click the image for a larger version.

This is an early sketch taken from "Driving Ambition" which shows the flow paths of the air in, around, and under the McLaren F1. The blue arrows imply cold air, the red imply hot exiting air and I'm not certain what the green arrows imply - maybe just clean air paths coming off the car.

A few of these things, like the "Idling Air Exit" in the nose didn't carry over to production F1s. I'm sure that some of the routing in the rear may have also changed slightly too. Anyay this should give a good visual explanation for those who haven't seen it.

>8^)
ER

[zx4000]

Originally Posted by Mr. Bernoulli

Hope this explains what you were after zx4000. If you have any problems with my rather long-winded explanation please post and I will try and expain myself better.

You answered about my question quite well and I really appreciated for your answers with porsche and peloton25,fairly satisfied with that. As to 10% of doubt(I think that it's exactly my ignorance )is my share, need to think myself.Everytime what i feel is that this site is so much useful.
Thank a lot once again.
If i also have a another question, could you give more help?(all the time)
and did Mr.Bernoulli get your id from bernolli's principle? just curious.

[Mr. Bernoulli]

Originally Posted by zx4000

If i also have a another question, could you give more help?(all the time)

Sure no probs.

Originally Posted by zx4000

and did Mr.Bernoulli get your id from bernolli's principle? just curious.