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2014 Power Units


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#401 Scotracer

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Posted 05 March 2013 - 08:22

Two drivers in two identical 2014 F1 cars. One is at 12,500rpm in 4th and the other is at 10,500rpm in 5th. They both floor it. Who pulls ahead? It's not a trick question. Despite a slight horsepower disadvantage, the car in 4th gear will likely out accelerate the car in 5th.


Not if engine torque is dropping off the table. If you have reached max fuel flow but are still revving, you HAVE to throttle the engine. Simple arithmetic. The guy at 12,500rpm probably wouldn't accelerate any further and would need to shift up to get more torque.

The fuel flow limit will work like a rev limiter.



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#402 JimboJones

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Posted 05 March 2013 - 08:24

Ummm.......torque at the wheels, a product of the engine and the transmission, is generally quite important for determining acceleration


Yes, but peak power will always give greatest torque at the wheels, irrespective of gear.
You need to understand the basics first before formulating some elaborate argument.

Edited by JimboJones, 05 March 2013 - 08:28.


#403 Markn93

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Posted 05 March 2013 - 08:53

Is there any guarantee that the manufacturers will make similar (using the term losely) engines? Or is there a genuine chance one manufacturer may turn up with a far superior unit or conversely a far weaker one than the other two?

#404 Wuzak

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Posted 05 March 2013 - 09:57

Ummm.......torque at the wheels, a product of the engine and the transmission, is generally quite important for determining acceleration


Power = Force * Velocity

Force (thrust) = Power/Velocity

Force = mass * acceleration

Acceleration = Force/mass = Power / (mass * Velocity)

Edited by Wuzak, 05 March 2013 - 10:07.


#405 MrAerodynamicist

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Posted 05 March 2013 - 10:25

It's exactly what the manufacturers want though. More dependence on scavenging wasted energy through braking and exhaust means less energy through conventional means is necessary, meaning lower emissions and consumption.

Had there not been an artifical and long-standing ban on secondary power sources, I reckon we'd have seen KERS appear earlier than it did; it offers a worthwhile performance gain. On the increased amount front, it means it's moving away from a push-to-pass function to something more akin to a slightly more powerful engine. That should actually please those who have been bemoaning the general issue of gimmicks.

#406 Lazy

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Posted 05 March 2013 - 10:30

Indeed, I think this is the most interesting development in F1 for a long time.

#407 FPV GTHO

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Posted 05 March 2013 - 10:35

Had there not been an artifical and long-standing ban on secondary power sources, I reckon we'd have seen KERS appear earlier than it did; it offers a worthwhile performance gain. On the increased amount front, it means it's moving away from a push-to-pass function to something more akin to a slightly more powerful engine. That should actually please those who have been bemoaning the general issue of gimmicks.


Weren't McLaren looking at it in the late 90's?

#408 Clatter

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Posted 05 March 2013 - 15:13

Is there any guarantee that the manufacturers will make similar (using the term losely) engines? Or is there a genuine chance one manufacturer may turn up with a far superior unit or conversely a far weaker one than the other two?


Depends which bit of the engine your talking about. If you mean the ICE then the rules are so tight that I expect them to all be very close as far as power is concerned, the KERS side of things could provide a bigger challenge between the teams. Reliability will be the big decider.

#409 phoenix101

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Posted 05 March 2013 - 20:13

Not if engine torque is dropping off the table. If you have reached max fuel flow but are still revving, you HAVE to throttle the engine. Simple arithmetic. The guy at 12,500rpm probably wouldn't accelerate any further and would need to shift up to get more torque.

The fuel flow limit will work like a rev limiter.


I'm operating under the assumption that, if the revs are available to the engineers, and they've already stated that the extra revs are to give energy recapture and KERS usage flexibility, they will not tune the engines such that they have no acceleration capability above 12,000rpm. If the engines do have torque limitations, they will supplement torque with KERS to maintain higher acceleration associated with staying in a lower gear for longer duration in the power band.

Perhaps this assumption about engine tuning will prove incorrect, but it appears to be the stated purpose of increasing the rev limit from 12,000rpm to 15,000rpm, and it doesn't seem particularly unreasonable considering the nature of racing. It looks like a push-to-pass system with dual benefit.

#410 phoenix101

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Posted 05 March 2013 - 20:18

Yes, but peak power will always give greatest torque at the wheels, irrespective of gear.
You need to understand the basics first before formulating some elaborate argument.


You're trolling. I get it now.

#411 DrProzac

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Posted 05 March 2013 - 21:03

Had there not been an artifical and long-standing ban on secondary power sources, I reckon we'd have seen KERS appear earlier than it did; it offers a worthwhile performance gain. On the increased amount front, it means it's moving away from a push-to-pass function to something more akin to a slightly more powerful engine. That should actually please those who have been bemoaning the general issue of gimmicks.

McLaren actually wanted to race a hydraulic KERS-like device in 1998. It got banned, as usual. Or maybe they even raced it once?
http://grandprix.com/ns/ns01518.html

This I like - innovative thinking, not rules practically forcing you to use certain solutions.

#412 JimboJones

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Posted 05 March 2013 - 21:19

You're trolling. I get it now.


No... I'm just right.

I'm operating under the assumption that, if the revs are available to the engineers, and they've already stated that the extra revs are to give energy recapture and KERS usage flexibility, they will not tune the engines such that they have no acceleration capability above 12,000rpm. If the engines do have torque limitations, they will supplement torque with KERS to maintain higher acceleration associated with staying in a lower gear for longer duration in the power band.

Perhaps this assumption about engine tuning will prove incorrect, but it appears to be the stated purpose of increasing the rev limit from 12,000rpm to 15,000rpm, and it doesn't seem particularly unreasonable considering the nature of racing. It looks like a push-to-pass system with dual benefit.


You're an idiot, i got it 5 posts ago...

#413 phoenix101

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Posted 05 March 2013 - 22:43

You're an idiot, i got it 5 posts ago...


You don't get it, not even a little bit.

Scotracer knew how to make a rebuttal, but as I opined, I don't think steeply diminishing torque output is a valid assumption, since the engineers asked for a revised rpm limit to exploit various energy recapture strategies. I can't imagine the engineers asking for useless rpm, unless it's a plot by the FOM to advertise significantly higher rpm limits than are practically observable.

I don't believe this to be the case, and even if it were, the teams would probably find a way to use the revised rev limit.

#414 l2k2

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Posted 06 March 2013 - 00:49

Ummm.......torque at the wheels, a product of the engine and the transmission, is generally quite important for determining acceleration


Yes it most definately is... and it's easy to calculate:
First the force accelerating the car: P = F * v, that is F = P / v.
Then the torque of the wheel: T = F * r_wheel, that is T = P / v * r_wheel.

One does not need to know the engine RPM or the gear ratio to do the computation. Of course the torque at the wheels is irrelevant (it depends on the wheel radius, whereas the acceleration does not). The only thing that does matter is the force applied to the tarmac.

F = P / v. Like most of us already know.

I'm operating under the assumption that, if the revs are available to the engineers, and they've already stated that the extra revs are to give energy recapture and KERS usage flexibility, they will not tune the engines such that they have no acceleration capability above 12,000rpm. If the engines do have torque limitations, they will supplement torque with KERS to maintain higher acceleration associated with staying in a lower gear for longer duration in the power band.

Perhaps this assumption about engine tuning will prove incorrect, but it appears to be the stated purpose of increasing the rev limit from 12,000rpm to 15,000rpm, and it doesn't seem particularly unreasonable considering the nature of racing. It looks like a push-to-pass system with dual benefit.


Why would one do that. (Unless for some dark magic, a 1.6 liter V6 can not consume 100 kg/h worth of fuel at 10500 RPM.) Because if you upshift you get the extra power from the engine. The KERS output remains the same. And thus, you get more power AND THUS faster acceleration. When passing, I would always use the maximum power. (This also applies on the road, that's why I only upshift after the peak power, not torque.)

Why not 12k limit (engineer point of view): the range from 10500 to 12000 (and 8 gears) gives only ratio of 2.91 between the slowest speed with peak power and the highest speed with below 12k. This means that we would only be able to "floor it" at over 120 kph. This is not a problem.
However, with 12k limit we would have the following speed ranges for given gears:
1st 0-130
2nd 130-150
3rd 150-175
4th 175-200
5th 200-225
6th 225-260
7th 260-300
8th 300-340
For the whole season. This would compromize quite a few medium-to-high speed corners (having to shift in the middle or run below 10500 RPM). With higher maximum RPM we can better control when to shift, thus having more time spent on the loud pedal. My (un-)educated guess is that they'll 10.5k-12k for the majority of time and 12k-13k at 8th gear and maybe at some corners (approach).

PS. I was nowhere near the first one to (try to) correct you. And, no, if someone does not share your opinion, he is not neccessary troll; it could be that you were wrong.

Not if engine torque is dropping off the table. If you have reached max fuel flow but are still revving, you HAVE to throttle the engine. Simple arithmetic. The guy at 12,500rpm probably wouldn't accelerate any further and would need to shift up to get more torque.

The fuel flow limit will work like a rev limiter.


Power = Force * Velocity

Force (thrust) = Power/Velocity

Force = mass * acceleration

Acceleration = Force/mass = Power / (mass * Velocity)



#415 Doughnut King

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Posted 06 March 2013 - 01:09

McLaren actually wanted to race a hydraulic KERS-like device in 1998. It got banned, as usual. Or maybe they even raced it once?
http://grandprix.com/ns/ns01518.html

This I like - innovative thinking, not rules practically forcing you to use certain solutions.


So we might have lost over a decade of racing development of this device?

#416 BigCHrome

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Posted 06 March 2013 - 01:26

Is there any guarantee that the manufacturers will make similar (using the term losely) engines? Or is there a genuine chance one manufacturer may turn up with a far superior unit or conversely a far weaker one than the other two?


Unfortunately the rules are very tight, so it's not likely there will be many differences between the engines. We might have different ratios between high end power/mid range power/cooling like it is now, but I don't think it will be like in the early 2000s.

Had there not been an artifical and long-standing ban on secondary power sources, I reckon we'd have seen KERS appear earlier than it did; it offers a worthwhile performance gain. On the increased amount front, it means it's moving away from a push-to-pass function to something more akin to a slightly more powerful engine. That should actually please those who have been bemoaning the general issue of gimmicks.


I don't think KERS was ever realistically intended as a push to pass mechanism. It was a "green" initiative by Mosley, even though the batteries are extremely toxic.


#417 phoenix101

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Posted 06 March 2013 - 03:51

Then the torque of the wheel: T = F * r_wheel, that is T = P / v * r_wheel.


Since power is a derivative of torque in this instance (reciprocating piston engine) the substitution you made doesn't work. You get T = (T/t)/v * r_wheel [(t) is unit time]. If you have torque on one side of the equation and torque on the other side of the equation, you're in trouble. For the equation to be true, the superfluous functions and values must equal 1, and that's the problem with using the P/v substitution for a reciprocating ICE.

T = mass * acceleration * r_wheel

This equation is more interesting. We sort of know that the engine torque curve is constant at constant throttle. For simplicities sake we can assume the mass of the vehicle is constant, though fuel is being burned. The equation tells us that acceleration has an inverse relationship with the radius of the rear wheel. Predictable. The inverse of the inverse is also true, meaning lengthening the radius of the gears (increasing the gear ratio) increases acceleration. Also predictable.

If you launch the same car, consecutively in different gears, the rate of acceleration will vary despite using identical throttle and powerband. This should hardly be surprising to anyone. Therefore, the difference in torque generated by the gearing radii is as relevant to acceleration as the torque and power (force) derived from the engine at the crank.

That was the discussion I was having with Scotracer. The nature of the powerband above 10,500rpm and the fuel consumption strategies should determine the shift points.


#418 FPV GTHO

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Posted 06 March 2013 - 06:23

Ive been doing some thinking and playing with http://www.my330i.com/gears.php#A

I came up with a set of ratios and max speeds as follows:

1st - 5.3478/68.88mph@12000rpm/86.10mph@15000rpm
2nd - 4.6793/78.72mph@12000rpm/98.40mph@15000rpm
3st - 4.0943/89.97mph@12000rpm/112.46mph@15000rpm
4nd - 3.5826/102.82mph@12000rpm/128.52mph@15000rpm
5rd - 3.1347/117.51mph@12000rpm/146.89mph@15000rpm
6th - 2.7428/134.30mph@12000rpm/167.87mph@15000rpm
7th - 2.4/153.48mph@12000rpm/191.85mph@15000rpm
8th - 2.1/175.41mph@12000rpm/219.26mph@15000rpm
Final - 2.5

Based on what we know, theres a 15000rpm rev limit, max fuel flow from 10500rpm and the tyres are 325mm wide, 13in rim and 660mm tall.

Now what everyone is assuming is max torque will be at 10500rpm. From the tyre regs its not advertised their aspect ratio either, so (660mm-(25.4x13))/2/325=~50% aspect ratio.

So i matched all the ratios so that each gear needed to shift at 12000rpm to hit 10500rpm in the following gear.


#419 l2k2

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Posted 06 March 2013 - 07:12

Since power is a derivative of torque in this instance (reciprocating piston engine) the substitution you made doesn't work. You get T = (T/t)/v * r_wheel [(t) is unit time]. If you have torque on one side of the equation and torque on the other side of the equation, you're in trouble. For the equation to be true, the superfluous functions and values must equal 1, and that's the problem with using the P/v substitution for a reciprocating ICE.

T = mass * acceleration * r_wheel

This equation is more interesting. We sort of know that the engine torque curve is constant at constant throttle. For simplicities sake we can assume the mass of the vehicle is constant, though fuel is being burned. The equation tells us that acceleration has an inverse relationship with the radius of the rear wheel. Predictable. The inverse of the inverse is also true, meaning lengthening the radius of the gears (increasing the gear ratio) increases acceleration. Also predictable.

If you launch the same car, consecutively in different gears, the rate of acceleration will vary despite using identical throttle and powerband. This should hardly be surprising to anyone. Therefore, the difference in torque generated by the gearing radii is as relevant to acceleration as the torque and power (force) derived from the engine at the crank.

That was the discussion I was having with Scotracer. The nature of the powerband above 10,500rpm and the fuel consumption strategies should determine the shift points.

I sew what you did there... Hate to say, but 'your physics' are not working here in this world. (Here: w = omega = angular velocity.)

P_engine = T_engine * w_engine NOT T_engine / t_unit. Although inverse time, frequency, and angular velocity have the same unit they are not the same physical quantity.

Also for your other 'point': "If you launch the same car, consecutively in different gears, the rate of acceleration will vary despite using identical throttle and powerband."

Let us use entirely torque based calculation:
at the end of engine: T_engine, w_engine.
at the end of gearbox (no losses in my gearbox): T_gearbox = T_engine * gear_ratio, w_gearbox = w_engine / w_gearbox.
after the final ratio: T_wheelaxis = T_gearbox * final_ratio = T_engine * gear_ratio * final_ratio, w_wheelaxis = w_gearbox / final_ratio = w_engine / gear_ratio / final_ratio.
Thus, at the wheel contact surface:
F_contact = T_wheelaxis / r_wheel = T_engine * gear_ratio * final_ratio / r_wheel, v_contact = w_wheelaxis * r_wheel = w_engine / gear_ratio / final_ratio * r_wheel.

But, v_contact = v.
v = v_contact = w_engine / (gear_ratio * final_ratio) * r_wheel,
thus
gear_ratio * final_ratio / r_wheel = w_engine / v.
And so,
F_contact = T_engine * (gear_ratio * final_ratio / r_wheel) = T_engine * w_engine / v = P_engine / v.

Physics, it just works. :love:

PS. The formula P = F / v works for any engine. Indeed, one can derive it directly from Newton's second law and the 'work law' W = F * (r_final - r_initial).
PPS. Did you 'unit test' your unity 1/t/v*r? [1/t/v*r] = 1/[s]/[m/s]*[m] = 1. At least it is dimensionless. (And when using the correct formula T = (T*w)/v*r = T*w/(v/r) = T * 1 = T.)

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#420 Giz

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Posted 06 March 2013 - 07:27

I have literally no idea what you guys are talking about but it sounds amazing and I can't wait for next year

#421 JimboJones

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Posted 06 March 2013 - 08:00

I have literally no idea what you guys are talking about but it sounds amazing and I can't wait for next year


:up:

l2k2, you have more patience than I, and I applaud your effort. But let's see if pheonix is actually capable of listening.
It's GCSE physics...

Edited by JimboJones, 06 March 2013 - 08:01.


#422 Giz

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Posted 06 March 2013 - 09:03

:up:

l2k2, you have more patience than I, and I applaud your effort. But let's see if pheonix is actually capable of listening.
It's GCSE physics...


I did my GCSEs in '95 and got AA in Science and either I've forgotten it or we never did anything like what you were describing above!

To be fair knowing me I've probably forgotten it......

#423 phoenix101

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Posted 06 March 2013 - 09:57

I have literally no idea what you guys are talking about but it sounds amazing and I can't wait for next year


This is Jimbo's and l2k2's attempt to convince everyone that, if two identical cars are rolling along at idle, one in 1st gear and one in 3rd gear, both cars will exhibit identical acceleration when the driver applies 100% throttle. Apparently, common fans cannot observe this performance phenomenon b/c we lack a PhD in physics.

They need to make their point to dispel the myth that F1 engineers are planning to use the 3,000 extra rpm they requested. If you have a PhD in physics, you understand that F1 engineers only asked for an additional 3,000rpm b/c it looks nice on paper.

#424 Giz

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Posted 06 March 2013 - 10:12

This is Jimbo's and l2k2's attempt to convince everyone that, if two identical cars are rolling along at idle, one in 1st gear and one in 3rd gear, both cars will exhibit identical acceleration when the driver applies 100% throttle. Apparently, common fans cannot observe this performance phenomenon b/c we lack a PhD in physics.

They need to make their point to dispel the myth that F1 engineers are planning to use the 3,000 extra rpm they requested. If you have a PhD in physics, you understand that F1 engineers only asked for an additional 3,000rpm b/c it looks nice on paper.


Ok.... like I said the sums are going over my head and I'm here to learn not to wade in on the debate so perhaps someone can correct me on my thinking and it could be part of the new technologies....

Engines generally accelerate faster in the lower gears due to the way the gear ratios work? As you get higher up the 'box the acceleration curve flattens to allow an increase in top speed meaning eventually you need a massive amount of power just to get the wheels turning if you are trying to set off in too high a gear.

So I guess 1 side is saying yes they'll use the extra 3000 rpm to provide the extra power in higher gears to maintain acceleration and the other side is saying they won't for some other technical reason (fuel flow limit?)


#425 saudoso

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Posted 06 March 2013 - 11:08

It's too early to say, but it's pretty easy to figure out: You have to maximise the area under the power curve.

If power starts falling quickier to the right of 10500 than it fall to the left they will shift at 10500. If it holds falling gentler to the right let's say up to 12000, that's where they will shift. If KERS keeps the curve flat up to 15000, that's where thet wil shift.

Simple. Biggest area under the power curve, all gadgetry included.

Which no one here kows yet. So we can't tell.

Edited by saudoso, 06 March 2013 - 20:19.


#426 FPV GTHO

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Posted 06 March 2013 - 11:12

Well they won't be shifting at 10500rpm, that much is obvious.

Peak power always occurs after peak torque, as torque tends not to drop off drastically straight after peak and the higher revs still allow more power to be made.

#427 Scotracer

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Posted 06 March 2013 - 11:16

This is Jimbo's and l2k2's attempt to convince everyone that, if two identical cars are rolling along at idle, one in 1st gear and one in 3rd gear, both cars will exhibit identical acceleration when the driver applies 100% throttle. Apparently, common fans cannot observe this performance phenomenon b/c we lack a PhD in physics.

They need to make their point to dispel the myth that F1 engineers are planning to use the 3,000 extra rpm they requested. If you have a PhD in physics, you understand that F1 engineers only asked for an additional 3,000rpm b/c it looks nice on paper.


I might not have a PhD in physics but I do have a Masters in Aerospace Engineering and I design car engine parts for a living. I'd hope I at least understand this concept.

The point is, if you limit fuel flow above 10,500rpm the torque has to start dropping off from that point towards the imposed engine rev limit. Even if you remained WOT it HAS to decrease because the amount of charge you can supply the engine is below the peak (think of it as volumetric efficiency dropping off). Here is a predicted engine torque curve for F1 2014 engines from SAE paper I read recently (I cannot link the paper as I get access through my work):

Posted Image

The paper is 2012-01-1802 (KERS braking in 2014 F1).

Take a look at the projected torque curve of the two 2014 engines beyond 10500rpm - it drops right off. As you've told us and we've reiterated in this thread, it's torque (therefore thrust) at the wheels we care about...so if torque is dropping off in 4th passed 10,500rpm then it would be quicker to change to 5th to get back in to the meat of the torque. It is a natural rev limit.

Edited by Scotracer, 06 March 2013 - 11:17.


#428 Wuzak

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Posted 06 March 2013 - 11:47

I might not have a PhD in physics but I do have a Masters in Aerospace Engineering and I design car engine parts for a living. I'd hope I at least understand this concept.

The point is, if you limit fuel flow above 10,500rpm the torque has to start dropping off from that point towards the imposed engine rev limit. Even if you remained WOT it HAS to decrease because the amount of charge you can supply the engine is below the peak (think of it as volumetric efficiency dropping off). Here is a predicted engine torque curve for F1 2014 engines from SAE paper I read recently (I cannot link the paper as I get access through my work):

Posted Image

The paper is 2012-01-1802 (KERS braking in 2014 F1).

Take a look at the projected torque curve of the two 2014 engines beyond 10500rpm - it drops right off. As you've told us and we've reiterated in this thread, it's torque (therefore thrust) at the wheels we care about...so if torque is dropping off in 4th passed 10,500rpm then it would be quicker to change to 5th to get back in to the meat of the torque. It is a natural rev limit.


That is interesting.

If we use the lower estimate (target 475kW) the power at 15,000rpm is about 470kW/630hp. Power is around the 475kW/637hp from 13,500rpm to 14,500rpm. Power at 10,500rpm is around 400kW/535hp. This would suggest that they will upshift at 15,000rpm.

Question, does this graph include the energy recovered from the MGUH and used directly in the MGUK? That would explain the power increasing compared to most people's thoughts that maximum power will occur at 10,500rpm.

#429 FPV GTHO

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Posted 06 March 2013 - 14:01

That would explain the power increasing compared to most people's thoughts that maximum power will occur at 10,500rpm.


I thought most people thought max torque would occur at 10,500rpm

#430 Clatter

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Posted 06 March 2013 - 14:09

So we might have lost over a decade of racing development of this device?


There's no might about it.

#431 Rubens Hakkamacher

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Posted 06 March 2013 - 14:38

For some reason, your brain appears to lack the capacity to understand the difference between fuel efficiency and thermal efficiency.


Ah, personal attacks.

In 2014, the fuel will be limited to 100kg per race / 100kg an hour flow.

Thermal efficiency does not mean you have endless amounts of fuel. The mere fact they've put a limit on how much fuel they can use says FUEL EFFICIENCY will matter. You don't put a limit on something if the limit is never expected to be reached. They in turn expect it to be reached as a performance modifier.

If you don't understand the difference between fuel efficiency and thermal efficiency, NASCAR is probably the best motorsport for you.


Oooh, BURNNNN!




#432 l2k2

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Posted 06 March 2013 - 14:41

I thought most people thought max torque would occur at 10,500rpm


Why would the maximum torque occur at that late RPM? The fuel flow limit is:

0.009*RPM+5, if RPM < 10500,
100, otherwise,
and in units kg/h.

This means that there is always (slightly) more gasoline per stroke at lower RPM. Thus, the peak torque can occur at a much lower engine RPM. I would have placed the peak torque at approximately 8000 RPM, however my model suggested a much lower value (which is below the valid region for the model). In any case, the new-engine concept seems to be used only above peak torque.

That is interesting.

If we use the lower estimate (target 475kW) the power at 15,000rpm is about 470kW/630hp. Power is around the 475kW/637hp from 13,500rpm to 14,500rpm. Power at 10,500rpm is around 400kW/535hp. This would suggest that they will upshift at 15,000rpm.

Question, does this graph include the energy recovered from the MGUH and used directly in the MGUK? That would explain the power increasing compared to most people's thoughts that maximum power will occur at 10,500rpm.


Yes, the given torque curve is interesting. If we assume that it is true, then they will upshift at 15k – because it is the power peak...

However, the curve is very different from what my estimation has predicted. Here are my 2 cents to this thread; the power and torque estimated based on solely thermal efficiency and a (very) small drag parameter.

Posted Image

PS. And yes, they do look like ones for an electric motor... With these numbers, just 3 or 4 gears would suffice for optimal acceleration. :drunk: (In reality, we can sharpen the power peak by tuning the exhaust manifold; at the cost of maximum practical RPM. :smoking: )



#433 Rubens Hakkamacher

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Posted 06 March 2013 - 14:45

according to your definition, we should bring back steam engine,


No. Look up "straw man".


for each of rejecting 'RACING PURIST' there will be 100's of general fans who'll not give 2 cents on sentiments.


We'll see. If nobody runs out of fuel, and nobody gets the "watch your fuel" warning - it won't matter. The moment the races comes down to seeing who will make it to the end, or who can driver moderately enough to make it first to the end - "general fans" may go elsewhere.



#434 Clatter

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Posted 06 March 2013 - 14:53

No idea what revs will actually be used, but it does sound like they won't be hitting the limiter as soon as they get in the slipstream

#435 Rubens Hakkamacher

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Posted 06 March 2013 - 14:54

it's mostly due to the bad recording quality of the video. do you really think that's what a engine trully sounds like???? if u visit a real race track, even the GP2s will howl and scream.



It's not from bad recording, the pitch and musicality remains the same. It's not revving to 19,000. 12,000 does not "scream" like 19,000, and cannot. The 2014 will inherently not sound as impressive as the present engines in the swing of pitch, volume, and with a single exhaust (uhg.. WTF?) timbre.



#436 Rubens Hakkamacher

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Posted 06 March 2013 - 14:57

you can almost guarantee they have designed the engines and firing orders so that they sound more impressive.



Nobody is designing engines to sound a certain way.


I think it will probably sound more like a Ferrari 412t1


A 3 liter 12 cylinder engine? No...





#437 senna da silva

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Posted 06 March 2013 - 15:29

I find it curious that the discussion is centred on the ICE when the system is being designed as a unit.

#438 Scotracer

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Posted 06 March 2013 - 15:55

It's not from bad recording, the pitch and musicality remains the same. It's not revving to 19,000. 12,000 does not "scream" like 19,000, and cannot. The 2014 will inherently not sound as impressive as the present engines in the swing of pitch, volume, and with a single exhaust (uhg.. WTF?) timbre.


What on earth is wrong with a single exhaust? The single exhaust will INCREASE the pitch of the sound.



#439 7MGTEsup

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Posted 06 March 2013 - 16:13

We'll see. If nobody runs out of fuel, and nobody gets the "watch your fuel" warning - it won't matter. The moment the races comes down to seeing who will make it to the end, or who can driver moderately enough to make it first to the end - "general fans" may go elsewhere.


Welcome to Formula 1 from 1985 - 1988 where cars regularly ran out of fuel or had to slow to conserve fuel. But I don't see people moaning about that era or the fans didn't leave in droves back then. The cars back then only reved to about 12000rpm but they still developed a good sound and plenty of volume. I have grown pretty tired of the angry bee in a jam jar sound of recent F1 cars.

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#440 Boing Ball

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Posted 06 March 2013 - 16:24

Don't know how useful this is, but here's a recent, good quality recording of FW11 running: .

#441 phoenix101

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Posted 06 March 2013 - 16:49

I might not have a PhD in physics but I do have a Masters in Aerospace Engineering


That's probably why your argument made sense from the beginning. However, the SAE graphs you've provided show a relatively steep (compared to 10,500rpm-12,000rpm) drop beyond 12,000rpm. We will find out if falling torque output and parasitic frictional losses are sufficient to act as a rev limit in 2014. Some have already suggested that torque is only falling according to the equation for horsepower. I'm not a big fan of Nm so I will take their word for it.

#442 muramasa

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Posted 06 March 2013 - 17:06

Don't know how useful this is, but here's a recent, good quality recording of FW11 running: .

how bout MP4/4 and MP4/5 running together :D :love:




maybe nothing beats Mazda 787B tho :drunk:
(@0:35)


#443 Boing Ball

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Posted 06 March 2013 - 17:14

how bout MP4/4 and MP4/5 running together :D :love:


That's nice, I expected the turbo car to be much quieter, not so after all. You can hear both.


#444 phoenix101

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Posted 06 March 2013 - 17:14

The mere fact they've put a limit on how much fuel they can use says FUEL EFFICIENCY will matter.


The fuel efficiency is set for each race. The cars will all travel the same distance with up to 100kg at the same maximum fuel flow, thus, F1 is not really a fuel efficiency competition. The engineers have one primary mission: Maximize power output over race distance by increasing thermal efficiency, and figure out how to use the power effectively to make the biggest reduction in lap time.

I think the new engines will sound like the 412t1 b/c Ferrari were allegedly behind the switch to 90-degree V6's. The 412t1 was a 90-degree V12. The t1 was 12-into-2 and the new V6 will be 6-into-1. A 4-cylinder engine with 4-into-1 and a 180 degree crank produces roughly the same engine note as a V8 with 8-into-2 with 180 degree crank.

I don't know what crank was used in the 412t1/2, nor do I remember what crank will be used in the new V6, but I'm working under the assumption that everyone wants the cars to sound impressive.

Edited by phoenix101, 06 March 2013 - 17:22.


#445 BillBald

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Posted 06 March 2013 - 17:19

This is Jimbo's and l2k2's attempt to convince everyone that, if two identical cars are rolling along at idle, one in 1st gear and one in 3rd gear, both cars will exhibit identical acceleration when the driver applies 100% throttle. Apparently, common fans cannot observe this performance phenomenon b/c we lack a PhD in physics.

They need to make their point to dispel the myth that F1 engineers are planning to use the 3,000 extra rpm they requested. If you have a PhD in physics, you understand that F1 engineers only asked for an additional 3,000rpm b/c it looks nice on paper.


It seems obvious why the engineers asked for a higher rev limit, it's so that a car which has the benefit of slipstream plus DRS and/or ERS can go faster than it otherwise would. A car which is geared so that it hits 12,000 rpm in top gear near the end of the straight will be able to go faster for overtaking, because it will be able to pull more revs with the aid of those other elements.

This should hopefully finally solve the overtaking problem we've seen ever since rev limits were introduced, where there is an absolute limit to how fast a car can go, which is usually quite close to its top speed in normal running.

The question being debated about acceleration in lower gears is simply not relevant, AFAICS.



#446 muramasa

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Posted 06 March 2013 - 17:25

That's nice, I expected the turbo car to be much quieter, not so after all. You can hear both.

yea v10 in higher note and v6 in thick bass, both are nice and loud and when the 2 two run together it's quite awesome.

ps maybe this vid is better




#447 saudoso

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Posted 06 March 2013 - 18:43

Posted Image

The paper is 2012-01-1802 (KERS braking in 2014 F1).

Take a look at the projected torque curve of the two 2014 engines beyond 10500rpm - it drops right off. As you've told us and we've reiterated in this thread, it's torque (therefore thrust) at the wheels we care about...so if torque is dropping off in 4th passed 10,500rpm then it would be quicker to change to 5th to get back in to the meat of the torque. It is a natural rev limit.


I won't argue your background or education, but your analysis is wrong. Let's not get back to the Torque X Power argument, but the Torque curve is irrelevant when you look at the most possible amount of energy to be transferred from the engine to the car. You have to look at the power curve. And maximising the area under the power curve is maximizing the amount of energy transferred.

If the blue power curve below is correct (and I don't know if it is) they will shift right there at the 15K limiter.


Posted Image

Btw, thanks for the chart.

#448 DrProzac

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Posted 06 March 2013 - 19:36

Yes, but peak power will always give greatest torque at the wheels, irrespective of gear.
You need to understand the basics first before formulating some elaborate argument.

That's not right. At peak engine power, the engine torque is (in practice) lower than the maximum. Gearing doesn't affect the torque curve* so the torque at wheels will be greatest at the peak engine torque rpm, not peak power rpm.

* - ok, drivetrain power losses won't be perfectly constant when speed changes, but I assume the effect is pretty meaningless.

Take a look at the projected torque curve of the two 2014 engines beyond 10500rpm - it drops right off. As you've told us and we've reiterated in this thread, it's torque (therefore thrust) at the wheels we care about...so if torque is dropping off in 4th passed 10,500rpm then it would be quicker to change to 5th to get back in to the meat of the torque. It is a natural rev limit.

Interesting, thanks.
When you upshift the torque at wheels drops due to gear ratio change. If power is there and the change in engine torque (due to engine rev drop) isn't big enough that I'd guess that shifting later is a valid strategy, whichever way one might look at it. Correct me if I'm wrong.

#449 saudoso

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Posted 06 March 2013 - 19:49

That's not right. At peak engine power, the engine torque is (in practice) lower than the maximum. Gearing doesn't affect the torque curve* so the torque at wheels will be greatest at the peak engine torque rpm, not peak power rpm.



In a given gear ,yes.

But you are comparing two different gears (discussing gear shifts) and if you can't grab the concept that power is Force x Velocity and at any moment, at a given car speed, the gear that will deliver more torque to the wheels is the one that has the engine at it's highest POWER curve position you should stay clear of these discussions. Because you don't know what a gearbox is built for or the basic principles of it's operation.

Edited by saudoso, 06 March 2013 - 19:51.


#450 JimboJones

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Posted 06 March 2013 - 20:10

In a given gear ,yes.

But you are comparing two different gears (discussing gear shifts) and if you can't grab the concept that power is Force x Velocity and at any moment, at a given car speed, the gear that will deliver more torque to the wheels is the one that has the engine at it's highest POWER curve position you should stay clear of these discussions. Because you don't know what a gearbox is built for or the basic principles of it's operation.



You beat me to it, but I couldn't have put it better myself!
By the way I2k2, I think your estimate of torque/power curves is bang on, that SAE paper is complete rubbish...

Edited by JimboJones, 06 March 2013 - 20:15.