Why turbo´s in F1?

[WhiteBlue]

Here's a basic power and torque graph.
This assumes turbo is spooled from the get go.

http://s1010.photobucket.com/user/ducka ... 2.png.html

Probably posted in the wrong thread.
The power will be falling slightly from 10.500 rpm
All we need now is the corresponding power curve of the MGU-H.

[GitanesBlondes]

If F1 cars stop being bat---- crazy, no-one are going to be interested in watching them. I fear that in 10 years they will have closed wheels and a ford mondeo badge.

That is exaggeration. Cars with close to two tons of downforce cornering at 5g lateral acceleration are pretty special. The objective must be performance and not how to reach it. The required performance should be reached with the lowest possible use of resources. F1 has been exciting at times when power and performance was a fraction of what we have now.

You talk about what cars have 900-1000HP, and then mention the aerodynamics.

The aerodynamic focus has virtually no relevance to any production car the average consumer drives.

Those times you refer of F1 being exciting with less power and performance happened to be when the aerodynamics were still very rudimentary (at least compared to now) and did not feature oversized snow plow front wings.

I'd love very much to see F1 kick the addiction to aerodynamics and try a formula that relies more on mechanical grip and power than outright downforce. I don't think it would be the worst thing if the 4-wheel drift became a necessary skill on circuits again.

[Holm86]

Excuse my ignorance. But what kind of road cars do you have in mind with 900-1.000 hp? That figure is excessive even for F1. F1 does not need more than 750 hp. Actually if there is more progress on aerodynamic efficiency power requirement for equal performance will be reduced as it has over many years. F1 also does not need more performance. The consequential costs for track safety would be astronomical as run offs would have to be upgraded. I hope that we will be saved from unreflected changes that would only create problems. Chances are good with the fuel flow formula that future problems with excessive performance will be resolved by flow and race fuel budget reduction.

What kind of road cars had over 1000HP, let alone 1200 or even 1400 circa 1986 when the qualifying engines were producing that sort of output? What road cars even had 900HP-1000HP circa 2004/2005 when the V10's were at their peak for power?

F1 does need more than 750HP because it is entertaining to see high horsepower cars breaking loose around any given circuit. Remember, F1 is entertainment at the end of the day. If no one watches, there is no use for it. Safety has also improved quite tremendously. There is no need for any further runoff areas.

Don't forget, part of developing new things for auto manufacturers is to subject them to extreme conditions...what can be more beneficial than having an engine sustain high power levels? This isn't 1985 any longer, and the engineering challenge involved to let the cars reliably make that sort of power would be quite entertaining.

Only talking about horsepower is very simplistic. Horsepower in it self isn't entertaining. Otherwise why don't you just look at some freighters at the sea?? They have hundreds of thousands of horsepowers.

You don't find ANY roadcars that comes close to the power to weight ratio of F1 cars. That is what makes them so fast. And there's no roadcars out there that comes close to the amount of downforce an F1 car can generate. This is what makes F1 stand out. This is what makes it exiting. Not just horsepower figures.

The new regulations is very exiting IMO. Controlling power via fuel flow is something I've been hoping for a very long time.
Although I do dislike FIA's need to specify every single little bit of the engine. But now with efficiency is also brought into the game it makes it very exciting to me. Creating horsepower is not hard. Creating them efficiently is both hard and useful.

[Andres125sx]

If F1 cars stop being bat---- crazy, no-one are going to be interested in watching them. I fear that in 10 years they will have closed wheels and a ford mondeo badge.

That is exaggeration. Cars with close to two tons of downforce cornering at 5g lateral acceleration are pretty special. The objective must be performance and not how to reach it. The required performance should be reached with the lowest possible use of resources. F1 has been exciting at times when power and performance was a fraction of what we have now.

You talk about what cars have 900-1000HP, and then mention the aerodynamics.

The aerodynamic focus has virtually no relevance to any production car the average consumer drives.

Those times you refer of F1 being exciting with less power and performance happened to be when the aerodynamics were still very rudimentary (at least compared to now) and did not feature oversized snow plow front wings.

I'd love very much to see F1 kick the addiction to aerodynamics and try a formula that relies more on mechanical grip and power than outright downforce. I don't think it would be the worst thing if the 4-wheel drift became a necessary skill on circuits again.

Turbo engines plus the added ERS will be a lot more demanding for the drivers in this aspect. Not only a turbo engine does provide more torque by itself, but electric motors are the torque monsters, so I´m sure we´ll see a lot more slidings next year

[WhiteBlue]

I think we can forget about uncontrolled power in F1. The power control has become so sophisticated compared to 30 years ago that we will never see these things again. The first turbos were very primitive things with seconds of turbo lag. This time around the turbo lag will only apply between idle and race level rpm. If the MB video is anything close to reality we will see 8.000 rpm low engine speed in races. At that rpm level you will not have any turbo lag at all.

[olefud]

Electric motors have greatest torque at zero RPM and rather quickly output diminished torque with higher RPM. Not to provoke a sometimes touchy subject, but it’s power that counts not torque.

[WhiteBlue]

Electric motors have greatest torque at zero RPM and rather quickly output diminished torque with higher RPM. Not to provoke a sometimes touchy subject, but it’s power that counts not torque.

You are right there. The fact remains that drivers will demand torque by pushing the pedal. The ICE torque will be augmented by electric torque which has pretty much unlimited dynamics. So expect the power to rise quicker than before. The rev band in the race is somewhere between 8.000 and 12.000 rpm. But only from 8.000 to 10.500 you will have big power increase. So that is a rev band of 3.500 rpm for the gear box to distribute the power on. The V8s were using a band of 12.000 to 18.000. Much wider. Because you will not generally us the top gear you will have 7 gears in reality as you have now. I think your gearbox diagram will look different to today.

[Tim.Wright]

Electric motors have greatest torque at zero RPM and rather quickly output diminished torque with higher RPM. Not to provoke a sometimes touchy subject, but it’s power that counts not torque.

Thats not exactly true anymore with the way that modern brushless DC motors are controlled. The windings are rated to a particular current, and this gives you a rated torque. This torque is available to you from 0RPM up until the point at which the back emf starts to reduce the speed. So you get something like this:


Basically, it is the bottom half of a typical theoretical DC motor curve which has a linear torque drop-off from the stall torque to the no load speed. While the motor can mathematically still produce much higher torques at 0 RPM, the current rating of the winding simply does not allow it. So what you have is a normal "triangular" Torque vs speed characteristic but "chopped" at a torque limit imposed by the current limit of the windings.

You can go over this limit for short periods but it will heat up the coils because they are operating beyond their rated current. This is why most motor manufacturers will give you a peak torque (current is over the winding rating) and continuous torque rating (current is at the rated level of the winding).

These motors can certainly be run in motor and generator modes. I think these are used as KERs in F1 currently but I'm not sure about that.

[Tommy Cookers]

well said TW !!
just like a car engine, an electric motor can be regarded as having an infinite number of torque/rpm curves
not just the one curve that is specific to one declared and fixed voltage supply

driving a car we select moment-by-moment a suitable torque curve by our use of the accelerator pedal
driving is a series of movements from one part of one torque curve to the 'next part of another torque curve
eg as the car moves along the road and speed is increasing in a driver-controlled way
the EM does the same if the voltage is varied (so also the current and torque) moment-by-moment, equivalent to the accelerator
(of course with a fixed voltage the response will be crude eg as when we operate the starter with the car in gear)
in 2014 F1 the voltage variation is continuous ie automatically proportionate/seamless with both MGUH and MGUK action
effective if required at least as fast as the ICE throttle response

this is what we might categorise as servo type control, with such control the torque is allowed to and will briefly greatly exceed the level permitted for continuous operation (such control is not in principle specific to brushless machines)
AC brushless and DC brushless machines (similar things) are rather different to older and simpler machines and their operation

[WhiteBlue]

Can you please stop to refer to the brush less electric machines we are discussing here as DC machines! This is absolutely confusing. They are AC machines!

I had a long discussion in the MGU-H thread look here with flynfrog and after some ten posts we found that the things he called DC machines are in reality AC machines with integrated inverters. The inverters are supplied with DC but not the motors or MGUs! I think we need to be a bit more technically precise in order to stop this endless confusion.

The inverters are DC powered.
The MGUs are AC driven!

[Tim.Wright]

Can you please stop to refer to the brush less electric machines we are discussing here as DC machines! This is absolutely confusing. They are AC machines!

I agree that they are driven with an AC signal but they are still called brushless DC motors in the industry (by the manufacturers and the people using them).

You can of course call them what you want, but don't lambast anyone who use the industry definition.

[WhiteBlue]

I agree that they are driven with an AC signal but they are still called brushless DC motors in the industry (by the manufacturers and the people using them)...

They are not driven by a signal. They are driven by an articulated current that is absolutely essential for the working principle.

And they are not called DC machines in all industrialized countries. Particularly in Europe the manufacturers avoid this kind of confusing nomenclature. It appears to me that the confusion mainly comes from the US or other English spoken countries.

I respect your refusal to use the precise language for a technical discussion. Perhaps other users will join me in calling the MGUs by what thy are: AC machines.

[dren]

There is a 200NM torque limit for the MGUK, so full power cannot be realized until 5700 or so rpms.

[Tim.Wright]

And they are not called DC machines in all industrialized countries. Particularly in Europe the manufacturers avoid this kind of confusing nomenclature. It appears to me that the confusion mainly comes from the US or other English spoken countries.

I'm interested to see some examples of this. Not because I don't believe you but I would just like to see it for myself because everyone I have dealt with in the last 3 years on a related project (in Europe btw) are referring to them as "BLDC" motors.

I remember being surprised at how they operate when I first looked into it. After the inverter, there is nothing DC in it at all.

[WhiteBlue]

I read a Siemens report about different drive designs and efficiencies.
This would be the source in German.