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      07-09-2013, 11:59 PM   #221
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      07-10-2013, 04:34 AM   #222
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Quote:
Originally Posted by solstice View Post
I understand what they are doing and I suspect they have investigated it but I'm not in anyway or form convinced that driving a turbine optimized for exhaust sourced energy is the most efficient use of the electrical energy you have access to.

Do you think it makes sense from a scientific/engineering aspect that an exhaust driven turbine just happen to be optimal to also be driven by an electrical device?

You should be able to separate energy generation and the use of it. I.e independent of what boost device you use, you can use the same device for re-generation.

Do I think I know better than Renault's and BMW engine cream of the crop engineers? No, but from a pure scientific aspect there are question marks of efficiency.

I think you misunderstood my "off boost", I meant when the turbos are below minimum boost, I.e both to keep the system pressurized when the intake is closed and keep a constant flow of the same boost from opening until the turbos spins up and take over.
I'm not an expert on turbos, but a centrifugal supercharger (like Paxton, ProCharger etc) are basically a compressor part of a turbo, driven by a belt off the crank. So, I don't see any issues with a electrical motor driving a turbo, in fact that would be even better suited than a belt drive off the crank because an electrical motor can change rpm's independently of the crank rpm. I might be proven wrong, but that solution seems to me to be much better, engineeringwise. You don't have to add a extra pump and the required valving and hardware needed for that pump. Just add an electrical motor/generator to the existing "pump" (turbo).

And, a turbo is designed to be propelled by exhaust. But what the exhaust does is "only" to spin the turbine shaft, in effect changing the rpm of the turbine shaft and thereby the compressor part of the turbo can do it's job. Whether the turbine shaft is driven by exhaust or the electrical motor doesn't make any difference, does it?
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      07-10-2013, 05:34 AM   #223
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Quote:
Originally Posted by Boss330 View Post
I'm not an expert on turbos, but a centrifugal supercharger (like Paxton, ProCharger etc) are basically a compressor part of a turbo, driven by a belt off the crank. So, I don't see any issues with a electrical motor driving a turbo, in fact that would be even better suited than a belt drive off the crank because an electrical motor can change rpm's independently of the crank rpm. I might be proven wrong, but that solution seems to me to be much better, engineeringwise. You don't have to add a extra pump and the required valving and hardware needed for that pump. Just add an electrical motor/generator to the existing "pump" (turbo).

And, a turbo is designed to be propelled by exhaust. But what the exhaust does is "only" to spin the turbine shaft, in effect changing the rpm of the turbine shaft and thereby the compressor part of the turbo can do it's job. Whether the turbine shaft is driven by exhaust or the electrical motor doesn't make any difference, does it?
In theory, in practice to flow enough air to make a difference, it takes a very large amount of power.....I'm told a journal bearing turbo under full load uses 1000watts of power to drive just the bearings. Not the compressor load, just thrust bearing load. 1000watts from a 12v system is one large electric motor, just to overcome the bearing losses. The compressor requires a significant amount more than this to actually do the work it requires. You can work it out, but I'm guessing you would need 5000watts minimum. And what does that give you? when does it come into action? Everytime you are sitting at the lights idling? All the time you are cruising along the highway, just in case you want to give it some? 5000watts is around 370 Amps. That is cabling thicker than your thumb to handle that power, and draining the battery way faster than the alternator can charge. Not a practical solution.
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      07-10-2013, 05:37 AM   #224
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it's probably been posted in this thread already but BMW filed a patent in Germany for an electric (multiclutch) turbo offering less turbo lag. I'm not sure if this post was around the same time as the actual patent filing but the post is way back from October 2011:

http://f80.bimmerpost.com/forums/sho...d.php?t=597327
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      07-10-2013, 05:51 AM   #225
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Quote:
Originally Posted by NISFAN View Post
In theory, in practice to flow enough air to make a difference, it takes a very large amount of power.....I'm told a journal bearing turbo under full load uses 1000watts of power to drive just the bearings. Not the compressor load, just thrust bearing load. 1000watts from a 12v system is one large electric motor, just to overcome the bearing losses. The compressor requires a significant amount more than this to actually do the work it requires. You can work it out, but I'm guessing you would need 5000watts minimum. And what does that give you? when does it come into action? Everytime you are sitting at the lights idling? All the time you are cruising along the highway, just in case you want to give it some? 5000watts is around 370 Amps. That is cabling thicker than your thumb to handle that power, and draining the battery way faster than the alternator can charge. Not a practical solution.
1000W is around 1,3hp

In a high voltage circuit of, say 250V (as a KERS type circuit is) that is around 4amps...

5000W at 250V is 20amps.

A EV/Hybrid vehicle generally has 100-300V and the Prius has a voltage converter that can "boost" the voltage going to the electrical motors to 600V...

The electrical generator/motor on the F1 turbos are fairly big:







But the cabling isn't THAT big diameter, due to the high voltage they operate under.

If it can be made to work on a F1 engine, why not on a production engine? You would obviously need a energy storage unit for the high voltage units. And it won't be able to spool the turbo for prolonged periods of time without also being in a regeneration mode from time to time.

Last edited by Boss330; 07-10-2013 at 06:15 AM..
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      07-10-2013, 06:08 AM   #226
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Quote:
Originally Posted by Boss330 View Post
1000W is around 1,3hp

In a high voltage circuit of, say 250V (as a KERS type circuit is) that is around 4amps...

5000W at 250V is 20amps.

The electrical generator/motor on the F1 turbos are fairly big:







But the cabling isn't THAT big diameter, due to the high voltage they operate under.

If it can be made to work on a F1 engine, why not on a production engine? You would obviously need a energy storage unit for the high voltage units. And it won't be able to spool the turbo for prolonged periods of time without also being in a regeneration mode from time to time.
But now you are in the realms of adding AC/DC invertors, separate battery packs, etc. And for what benefit?

In a racing car, easy, as the power demand can be mapped for an individual circuit.

On a road going car, how do you predict a WOT event with enough time to drive an anti lag system that will be driven with much less energy than the normal energy fed into the system in the first place? It just makes no sense whatsoever.
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      07-10-2013, 07:10 AM   #227
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Quote:
Originally Posted by NISFAN View Post
But now you are in the realms of adding AC/DC invertors, separate battery packs, etc. And for what benefit?

In a racing car, easy, as the power demand can be mapped for an individual circuit.

On a road going car, how do you predict a WOT event with enough time to drive an anti lag system that will be driven with much less energy than the normal energy fed into the system in the first place? It just makes no sense whatsoever.
The LaFerrari, Mclaren P1 and Porsche 918 all use hybrid technology to add power. How far BMW has taken the hybrid tech on the next gen M3/M4 will be interesting to see.

And a hybrid/electric turbo can accelerate from 40,000 to 120,000 rpm in less than 450 ms. This rate of acceleration eliminates the turbo lag which is a major limiting factor on the performance of standard turbocharged engines.

http://en.wikipedia.org/wiki/Hybrid_turbocharger

The electric motor (MGU) reacts so much faster than the turbine would from exhaust gases, this is where you can loose most of the turbo lag. And as I mentioned earlier you could even have a "M-mode" where the MGU actually keeps the turbo spinning at a rpm where boost constantly is made during deceleration, part throttle and where the turbo would "be boosting" even before WOT. And while at WOT the MGU acts as a generator/boost controller, recuperating energy and controlling boost levels at the same time

From an article on BMW's electric turbo patents:

Quote:
The turbine and compressor spin on separate axles that can be uncoupled by a clutch — with the electric motor constantly running in the middle. During full-throttle starts, the electric motor runs the compressor in an instant-on fashion, virtually eliminating the time it would normally take the exhaust gases to spin up a traditional turbine. When the turbine's up to speed, the clutch engages the turbine shaft to run in conjunction with the electric motor. Naturally, all of this switchery happens at ridiculously high RPMs.

Now here's the cool part. Rather than using a wastegate to hold back the speed of the turbine, the electric motor-generator kicks into generate mode. The resulting electrical current flows back to the battery (or, potentially, to a supercapacitor), while the additional load from the generator regulates turbine speed.
http://jalopnik.com/5855317/will-bmw...-end-turbo-lag

Borg Warners eBooster:

Quote:
The eBooster permits the development of small and efficient high-performance turbocharged engines whose dynamic response matches that of large non-supercharged engines of the same output class. The superiority of the eBooster was impressively demonstrated in close cooperation with various customers for gasoline engines as well as for diesel engines.
http://www.3k-warner.de/products/eBooster.aspx

Bowman electric turbos for trucks:

http://www.bowmanpower.com/technolog...turbochargers/

Turbos with a electric generator/motor unit makes a lot of sense to me

Last edited by Boss330; 07-10-2013 at 07:17 AM..
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      07-10-2013, 07:29 AM   #228
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Quote:
Originally Posted by Boss330 View Post
The LaFerrari, Mclaren P1 and Porsche 918 all use hybrid technology to add power. How far BMW has taken the hybrid tech on the next gen M3/M4 will be interesting to see.

And a hybrid/electric turbo can accelerate from 40,000 to 120,000 rpm in less than 450 ms. This rate of acceleration eliminates the turbo lag which is a major limiting factor on the performance of standard turbocharged engines.

http://en.wikipedia.org/wiki/Hybrid_turbocharger

From an article on BMW's electric turbo patents:



http://jalopnik.com/5855317/will-bmw...-end-turbo-lag

Borg Warners eBooster:



http://www.3k-warner.de/products/eBooster.aspx

Bowman electric turbos for trucks:

http://www.bowmanpower.com/technolog...turbochargers/

Turbos with a electric generator/motor unit makes a lot of sense to me
Interesting that Honeywell Garrett, the worlds largest Turbo manufacturer came out with an electric assist patent and prototypes probably about a decade ago, yet have not gone any further with it......why do you think that is?

The other thing that makes me chuckle in your wiki link, is the whole reason for using turbo chargers in the first place is to use the efficiency of the low or unboosted state where the engine uses significantly less fuel. To add a device that artificially maintains boost, is surely defeating the object? May as well stay with a larger NA.

The biggest factor in Turbo lag is the inertia of the entire turbine unit. Hence the reason for using smaller turbo's to overcome the inertia issue. Also why some manufacturers use ceramic turbine blades instead of metallic ones, again to reduce weight of rotating mass and lower inertia....

....so someone thinks it is a good idea to add clutches and gearboxes to turbines significantly increasing inertia all to reduce lag? Doesn't take a rocket scientist to how anti productive that thinking is.

My guess is all this is more focussed on harvesting the 'wasted' energy than reducing lag.
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      07-10-2013, 07:57 AM   #229
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Quote:
Originally Posted by NISFAN View Post
Interesting that Honeywell Garrett, the worlds largest Turbo manufacturer came out with an electric assist patent and prototypes probably about a decade ago, yet have not gone any further with it......why do you think that is?

The other thing that makes me chuckle in your wiki link, is the whole reason for using turbo chargers in the first place is to use the efficiency of the low or unboosted state where the engine uses significantly less fuel. To add a device that artificially maintains boost, is surely defeating the object? May as well stay with a larger NA.

The biggest factor in Turbo lag is the inertia of the entire turbine unit. Hence the reason for using smaller turbo's to overcome the inertia issue. Also why some manufacturers use ceramic turbine blades instead of metallic ones, again to reduce weight of rotating mass and lower inertia....

....so someone thinks it is a good idea to add clutches and gearboxes to turbines significantly increasing inertia all to reduce lag? Doesn't take a rocket scientist to how anti productive that thinking is.

My guess is all this is more focussed on harvesting the 'wasted' energy than reducing lag.
Garrett Turbo's view on eBoosting:

http://www.acarplace. com/ cars/ turbochargers.html

Quote:
What is E-boosting and what are its prospects? E-boosting stands for electrical-assisted boosting; by incorporating a very high speed electrical motor in rotating assembly of a turbocharger, you can drive it up to very high speeds, before you have exhaust gases to do so. It is very powerful, specifically when there is no exhaust gas available, such as at idle, or in stop and go.

It is entirely integrated inside the turbocharger, with virtually “real-estate” penalty to speak of. The size of the electric motor is about an inch long. It makes the turbocharger an inch longer, with no impact on the timing and virtually no impact on the weight. The trick is to make electrical motors are capable of motoring more than 120,000 rpm and withstand mechanical loads in excess of 200,000 rpm – because turbos spin that fast.

The other challenge is to get enough electrical energy into their designs. The majority of cars use 12 volt or a 14-volt alternator.42 volt would be a significant help. But we believe that electric boost is feasible with 12-volt systems. The prospect is very real for electric boost. You will see it in premium diesels such as the Renault Aspach (sic) or the Peugeot A06 (in Europe). They have limited space and need lots of power density and bottom end. I also clearly see it in high-end gasoline engines, built for high performance.

I could imagine it in a (Chevrolet) Corvette or (Ford) Mustang Cobra like vehicle, having an electrical-assist turbo. If you go to 42 volt or a hybrid, e boosting would also allow very aggressive downsizing of the (IC) engine. This would allow very aggressive downsizing of the engine. Instead of applying a three-liter V6, you could apply a one-liter internal combustion engine, equipped with an electrical boost turbo plus an electric motor. You can only do extreme downsizing – 50 percent or more – with electrical assist turbocharging.
Garrett's final report on Electric Boosting Systems:

http://www.osti.gov/bridge/servlets/...ive/841240.pdf

This report provides very interesting reading!

http://www.bmwblog.com/2011/07/09/ed...trical-assist/

You oversimplify when you state the reason to go turbo is "to use the efficiency of the low or unboosted state where the engine uses significantly less fuel. To add a device that artificially maintains boost, is surely defeating the object? May as well stay with a larger NA."

What you are saying is that modern turbo engines don't boost before medium revs???

The fuel economy benefit of a smaller turbo engine vs a larger NA engine is more complicated than boost/no-boost:

Less cylinders means less frictional losses (significantly less). Fewer combustion cycles per rpm etc. A modern turbo engine is on boost from very low revs anyway. In a "M-mode" I wouldn't think fuel consumption was the main priority either...

It's not only inertia that is the reason for going to a smaller turbo. A large turbo will need larger amounts of exhaust gas to spool up but will be able to handle higher rpms and the resulting larger volumes of exhaust gases. A small turbo spools quicker as it's a smaller amount of exhaust gas needed to rotatet the turbine, but restricts exhaust gas flow at higher rpm's. This is also one area where the MGU would come into play. You can have a larger turbo, that can handle high rpm's, but with reduced lag from the assist of the MGU.

Last edited by Boss330; 07-10-2013 at 09:04 AM..
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      07-10-2013, 09:49 AM   #230
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Quote:
Originally Posted by Boss330 View Post
Garrett Turbo's view on eBoosting:

http://www.acarplace. com/ cars/ turbochargers.html



You oversimplify when you state the reason to go turbo is "to use the efficiency of the low or unboosted state where the engine uses significantly less fuel. To add a device that artificially maintains boost, is surely defeating the object? May as well stay with a larger NA."

Garrett's final report on Electric Boosting Systems:

http://www.osti.gov/bridge/servlets/...ive/841240.pdf

This report provides very interesting reading!

http://www.bmwblog.com/2011/07/09/ed...trical-assist/

What you are saying is that modern turbo engines don't boost before medium revs???

The fuel economy benefit of a smaller turbo engine vs a larger NA engine is more complicated than boost/no-boost:

Less cylinders means less frictional losses (significantly less). Fewer combustion cycles per rpm etc. A modern turbo engine is on boost from very low revs anyway. In a "M-mode" I wouldn't think fuel consumption was the main priority either...


Agreed on the smaller engine having lower frictional losses.

I'll point out a little scenario that helps understand why turbo engines are so fuel efficient.

Take a 335i cruising on the highway at 70. In this steady state it only needs about 50hp to maintain the speed. 50hp of airflow is not much at all, so the throttle valves will only just be cracked open. In this state, regardless of engine revs, very little energy is flowing through the turbo, therefore it runs slowly, and produces little to no boost. Here we have a turbo charged engine running in almost NA engine conditions. Good fuel economy.

Flipside time....

........we all know that a turbo engine on full booost runs stoichiometric-ally richer than an equivalent NA engine. Therefore on boost a turbo is LESS fuel efficient, power for power. Proof if needed that it is only at low-No boost conditions where a turbo engine is actually able to run more efficiently than a similarly powered NA. Frictional losses/weight of powertrain aside.

Quote:
Originally Posted by Boss330 View Post
It's not only inertia that is the reason for going to a smaller turbo. A large turbo will need larger amounts of exhaust gas to spool up but will be able to handle higher rpms and the resulting larger volumes of exhaust gases. A small turbo spools quicker as it's a smaller amount of exhaust gas needed to rotatet the turbine.
Well you do get two turbo's rated at similar flow, one having a smaller diameter than the other. In this case it is highly likely the smaller diameter one will have less inertia.
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      07-10-2013, 09:54 AM   #231
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One of the links above agrees with me

"What the electrical assist does is spin the turbine up to speed in very light to no load conditions. And the term ‘light to no load’ is the critical piece. Under load, you have to supply massive quantities of amps to the electric motor to generate the boost levels needed. But if all that is required is for the turbine to be spun up then an existing automotive electrical system will work just fine"

Suggests that automotive electrical systems are not powerful enough to produce positive boost pressure.....and yes you can fit a prius motor and 3 phase electrical system to drive a compressor, but really? an extra 100kg's to reduce lag by a few tenths?
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      07-10-2013, 10:19 AM   #232
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Quote:
Originally Posted by NISFAN View Post
One of the links above agrees with me

"What the electrical assist does is spin the turbine up to speed in very light to no load conditions. And the term ‘light to no load’ is the critical piece. Under load, you have to supply massive quantities of amps to the electric motor to generate the boost levels needed. But if all that is required is for the turbine to be spun up then an existing automotive electrical system will work just fine"

Suggests that automotive electrical systems are not powerful enough to produce positive boost pressure.....and yes you can fit a prius motor and 3 phase electrical system to drive a compressor, but really? an extra 100kg's to reduce lag by a few tenths?
That was from the low voltage system. The high voltage systems are able to make more power to the MGU. Just look at F1 next year...

To me it makes sense to have a MGU on a turbo, to you it don't. No problem

We'll just have to wait and see what the future brings
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      07-10-2013, 10:21 AM   #233
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Quote:
Originally Posted by NISFAN View Post
In theory, in practice to flow enough air to make a difference, it takes a very large amount of power.....I'm told a journal bearing turbo under full load uses 1000watts of power to drive just the bearings. Not the compressor load, just thrust bearing load. 1000watts from a 12v system is one large electric motor, just to overcome the bearing losses. The compressor requires a significant amount more than this to actually do the work it requires. You can work it out, but I'm guessing you would need 5000watts minimum. And what does that give you? when does it come into action? Everytime you are sitting at the lights idling? All the time you are cruising along the highway, just in case you want to give it some? 5000watts is around 370 Amps. That is cabling thicker than your thumb to handle that power, and draining the battery way faster than the alternator can charge. Not a practical solution.
The thrust load on the bearing is proportionnal to the load of the compressor itself. The less mass flow the compressor is pumping the less thrust (axial) load there is on the bearing. When the throttles are closed (or intake valves in the case of a valvetronic engine), the compressor does not need to pump much mass flow to maintain boost. So not much power is needed to maintain the boost level and not much power is required to overcome the friction caused by the thrust loading.

Quote:
Originally Posted by NISFAN View Post
Suggests that automotive electrical systems are not powerful enough to produce positive boost pressure.....and yes you can fit a prius motor and 3 phase electrical system to drive a compressor, but really? an extra 100kg's to reduce lag by a few tenths?
An electric assist may not have the power to supply full boost at full load (WOT and high RPM). But it may be able to sustain boost at lower load levels (partial throttle).

The electric motor can also prevent the turbo from spooling down. Even if the electrical system adds inertia to the system, if the electrical motor is able to maintain some speed in the turbo, intertia is less of an issue. At partial loads, the turbine is still contributing work to keep the rotor spinning, albeit not enough to maintain full boost. An electric motor would simply assist the turbine to maintain the speed of the rotor. The electric motor would just supply the delta work required to maintain boost, not the entire work.

Quote:
Originally Posted by NISFAN View Post
Interesting that Honeywell Garrett, the worlds largest Turbo manufacturer came out with an electric assist patent and prototypes probably about a decade ago, yet have not gone any further with it......why do you think that is?

I see the biggest challenge in all of this mostly with the control systems. Maybe 10 years ago, the control technologies were not there to support the concepts. Great strides have been made in electronics and computer control technology since.

Last edited by CanAutM3; 07-10-2013 at 10:56 AM..
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      07-10-2013, 10:32 AM   #234
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Quote:
Originally Posted by CanAutM3 View Post
The thrust load on the bearing is proportionnal to the load of the compressor itself. The less mass flow the compressor is pumping the less thrust (axial) load there is on the bearing. When the throttles are closed (or intake valves in the case of a valvetronic engine), the compressor does not need to pump much mass flow to maintain boost. So not much power is needed to maintain the boost level and not much power is required to overcome the friction caused by the thrust loading.
True, at the lower engine operating range.....you can buy electric turbo's on ebay. They add no power that you can feel despite being driven by quite a large 12v DC motor.
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      07-10-2013, 10:47 AM   #235
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Quote:
Originally Posted by NISFAN View Post
True, at the lower engine operating range.....you can buy electric turbo's on ebay. They add no power that you can feel despite being driven by quite a large 12v DC motor.
I don't know if you are missing the point or just playing dumb...

Those electric turbos on e-bay do not have an exhaust driven turbine to spin the compressor and maintain the boost once the mass flow demand increases.
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      07-10-2013, 11:12 AM   #236
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Personally I hope they just find a simple mechanical solution to reduce lag to industry leading level. I prefer that to a more complex electrical solution. F1 engines are reliable today but the number of times the KERS failed in it's early days were not few. I prefer the simplicity of NA engines and a change to FI is already enough added potential point of failures at one time. Not all FI engines are unreliable but BMW's TTs have their share of fuel delivery issues wether it's the N54 or N63.
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      07-10-2013, 11:14 AM   #237
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Quote:
Originally Posted by CanAutM3 View Post
I don't know if you are missing the point or just playing dumb...

Those electric turbos on e-bay do not have an exhaust driven turbine to spin the compressor and maintain the boost once the mass flow demand increases.
So you think they work at partial throttle like you said?
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      07-10-2013, 11:16 AM   #238
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Quote:
Originally Posted by CanAutM3 View Post
I don't know if you are missing the point or just playing dumb...

Those electric turbos on e-bay do not have an exhaust driven turbine to spin the compressor and maintain the boost once the mass flow demand increases.
I think it's futile to try to convince NISFAN on this (or any other matter ). Even with all the information out there and the technology allready being in use, he will not be convinced it has any place on a turbo I believe that to NISFAN the turbo is such a clever device, it can't be improved upon Nevermind that WRC cars have found the need to install anti lag devices, or that F1 next year will use the MGU both to regenerate energy and to boost the turbo as well as replace the wastegate.

Even with all the information from turbo manufacturers and Renault F1 about how the MGU can be used to spool up the turbo to avoid lag, NISFAN isn't convinced that this actually has any real world effect...
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      07-10-2013, 11:20 AM   #239
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Quote:
Originally Posted by NISFAN View Post
So you think they work at partial throttle like you said?
The e-bay stuff is not what we are talking about here...

In next years F1 technical regulations, the MGU unit is not allowed to operate at a higher rpm than 125.000. That would be sufficient for part throttle, right?

Quote:
MGU-H
The MGU-H is connected to the turbocharger. Acting as a generator, it absorbs power from the turbine shaft to recover heat energy from the exhaust gases. The electrical energy can be either directed to the MGU-K or to the battery for storage for later use. The MGU-H is also used to control the speed of the turbocharger to match the air requirement of the engine (eg to slow it down in place of a wastegate or to accelerate it to compensate for turbo-lag.)



Last edited by Boss330; 07-10-2013 at 11:27 AM..
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      07-10-2013, 11:54 AM   #240
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Quote:
Originally Posted by Boss330 View Post
I think it's futile to try to convince NISFAN on this (or any other matter ). Even with all the information out there and the technology allready being in use, he will not be convinced it has any place on a turbo I believe that to NISFAN the turbo is such a clever device, it can't be improved upon Nevermind that WRC cars have found the need to install anti lag devices, or that F1 next year will use the MGU both to regenerate energy and to boost the turbo as well as replace the wastegate.

Even with all the information from turbo manufacturers and Renault F1 about how the MGU can be used to spool up the turbo to avoid lag, NISFAN isn't convinced that this actually has any real world effect...
I think you are reading into F1 MGU a bit too much. F1 use an electric motor to provide 161hp directly onto the engine crankshaft. This is the primary use of the energy store. If you have an instantaneous 161hp + whatever power the ICE can give you, that in itself is a lag minimising effect.

The Turbo generator is to enable an F1 car to HARVEST energy to recharge the battery to give the 161 crank hp. It can't harvest that on brakes alone like they do in 2013.

Adding additional weight to something you are trying to keep low due to inertia, is counter productive. Simple science.

The simple fact is, if they didn't use ERS-K they would NOT have this device sitting on the Turbo.

No other form of racing uses this, of which there are many turbo charged classes....why? because there is no need for it.
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      07-10-2013, 12:15 PM   #241
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Quote:
Originally Posted by NISFAN View Post
I think you are reading into F1 MGU a bit too much. F1 use an electric motor to provide 161hp directly onto the engine crankshaft. This is the primary use of the energy store. If you have an instantaneous 161hp + whatever power the ICE can give you, that in itself is a lag minimising effect.

The Turbo generator is to enable an F1 car to HARVEST energy to recharge the battery to give the 161 crank hp. It can't harvest that on brakes alone like they do in 2013.

Adding additional weight to something you are trying to keep low due to inertia, is counter productive. Simple science.

The simple fact is, if they didn't use ERS-K they would NOT have this device sitting on the Turbo.

No other form of racing uses this, of which there are many turbo charged classes....why? because there is no need for it.
Or, perhaps because it's not allowed? And this is also fairly new technology.

You have been privy to the process of F1 tech regulations and development since you can claim the following as a fact?

Quote:
The simple fact is, if they didn't use ERS-K they would NOT have this device sitting on the Turbo.
And F1 cars are NOT allowed to regenerate energy from the brakes as you claim, the regeneration is from the drivetrain under deceleration...

Quote:
9.10.1 The KERS must connect at any point in the rear wheel drivetrain before the differential.
http://www.fia.com/sites/default/fil...ONS-111212.pdf

Of course, one of the main objects of the MGU-H is to regenerate energy from the turbo. And it's not me who claims that it is also used to reduce lag, match the air flow of the engine and act as a wastegate. That's RENAULT F1's statement. If you disagree with them on that, please, be my guest

And the MGU-H is clutched to the turbine shaft, reducing the increase in inertia:

Quote:
5.2.4 The MGU-H must be solely mechanically linked to the exhaust turbine of a pressure charging system. This mechanical link must be of fixed speed ratio to the exhaust turbine and may be clutched.

The rotational speed of the MGU-H may not exceed 125,000rpm.
http://www.fia.com/sites/default/fil...08.07.2013.pdf

Last edited by Boss330; 07-10-2013 at 12:31 PM..
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      07-10-2013, 01:58 PM   #242
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how about adding a supercharger to the turbo? twin charged.
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