2014-2020 Formula One 1.6l V6 turbo engine formula

[WhiteBlue]

Wuzak, I'm aware of all these things. I just think that the pressure at the turbine inlet will very rapidly collapse from the moment you cut the injection. I do not have the thermodynamic computation which Ringo is better equipped to do, but the turbine cannot do any work if there is no energy added to the air that goes through the engine. The turbine cannot work on a bit of cold air. You also have to consider that the throttle will be closed and air intake to the engine will dramatically fall. So in fact you get a back pressure for the compressor due to the throttling which would slow the turbo even faster. You will have a very rapid turbine stall I believe.

[1158]

The turbo will be oil cooled. And that will heat up the oil a lot more than a N/A engine.

You think it will be oil cooled? My turbo has a ball bearing CHRA and it only requires a small amount of oil for lubrication. It uses engine coolant for cooling (had to add coolant lines). I was thinking the engine manufacturers would do the same.

[wuzak]

If we assume that the engine will have a throttle - which it surely will have due to banning variable valves - then the engine braking should simply work by cutting the injection. But that would also cause the turbo to spin down due to lack of exhaust energy. So it is difficult to imagine how this works without more information. It is not desirable to spin down the turbo if you have to spin it up again when you have to power out of the corner.

I agree with Holm that the MGU-K is much better suited to the purpose of braking.

IMO they will cut ignition and fuel when off throttle, but keep the throttle bodies open if this is allowed. And then use the MGU-K for braking the engine. This cold blowing will keep pumping air though the engine, helping the turbine to keep spinning. Then you can either use the MGU-H to harvest more energy from the turbine, or let the turbine spin freely so you don't have to use as much energy spinning it back up when back on the throttle.

There's so many variables in how to harvest and use the electric energy next year. Pretty exciting.

I am pondering this and it might be the answer. If the engines is running at 10500 rpm and at 21psi boost pressure
(52lbs/min of air flow) and then you were to kill the injectors and ignition the engine at this same rpm would now be flowing around 0 boost and (21lbs/min of air flow with the throttle WO) You would still have to add fuel to keep energy at the turbine and keep its rpm from dropping off due to MGUH load. So at this point you would have to go into ignition retard to power out of the engine and not lose a ton of turbine rpm?

I think that would be a waste of fuel.

You're engine braking, so the engine is slowing down. The air flow is reduced by the lower rpm and the closed throttle - it has to be closed, but whether or not it is full closed is another matter.

Reapplication of throttle won't (necessarily) require the same turbo flow/boost/speed as was the case before the heavy braking point (light braking, slight lift-offs will work differently). Power will be fed in, rather than jumping to full power straight away.

The power can be fed in using the MGUK while the ICE and turbo catch up, or the turbo can be spooled up to provide the quick response.

Slowing the turbo with the MGUH will generate a proportion of the energy required to spool up the turbo afterwards. Certainly not all of it, but some of the energy required.

[wuzak]

Wuzak, I'm aware of all these things. I just think that the pressure at the turbine inlet will very rapidly collapse from the moment you cut the injection. I do not have the thermodynamic computation which Ringo is better equipped to do, but the turbine cannot do any work if there is no energy added to the air that goes through the engine. The turbine cannot work on a bit of cold air. You also have to consider that the throttle will be closed and air intake to the engine will dramatically fall. So in fact you get a back pressure for the compressor due to the throttling which would slow the turbo even faster. You will have a very rapid turbine stall I believe.

That all depends onhow closed a closed throttle is.

You are also ignoring mass moment of inertia. That will be larger than for regular compressor due to the oversized turbine, which will increase the time it takes for the rotating assembly to slow down.

You could let the turbo slow by itself, but you miss out on some energy that can be extracted from the turbo's angular momentum.

[Holm86]

Wuzak, I'm aware of all these things. I just think that the pressure at the turbine inlet will very rapidly collapse from the moment you cut the injection. I do not have the thermodynamic computation which Ringo is better equipped to do, but the turbine cannot do any work if there is no energy added to the air that goes through the engine. The turbine cannot work on a bit of cold air. You also have to consider that the throttle will be closed and air intake to the engine will dramatically fall. So in fact you get a back pressure for the compressor due to the throttling which would slow the turbo even faster. You will have a very rapid turbine stall I believe.

WB that's why I'm suggesting that they will keep the throttle wide open when the driver goes off the throttle. Just like cold blowing last year. Last year cold blowing added flow via the exhaust the blow the diffuser. Next year it could flow through the turbine. I know the air wont have much energy but still better than nothing. And it also prevent back pressure in the compressor as the compressor just blows straight though the engine. IMO this sounds like the way to do it.

Don't know if cold blowing is illegal now? Or will be next year?? But if it is illegal I think they should remove the ban. Because this is the most energy efficient way to do it.

[1158]

WB that's why I'm suggesting that they will keep the throttle wide open when the driver goes off the throttle. Just like cold blowing last year. Last year cold blowing added flow via the exhaust the blow the diffuser. Next year it could flow through the turbine. I know the air wont have much energy but still better than nothing. And it also prevent back pressure in the compressor as the compressor just blows straight though the engine. IMO this sounds like the way to do it.

Don't know if cold blowing is illegal now? Or will be next year?? But if it is illegal I think they should remove the ban. Because this is the most energy efficient way to do it.

If this is legal I agree it is the way to go. It removes the issue of a BOV (extra weight and something else to go wrong) and makes plumbing a little easier. As you said it will also help keep the turbine moving. The effect is diminished but any little bit will help.

[Holm86]

If we assume that the engine will have a throttle - which it surely will have due to banning variable valves - then the engine braking should simply work by cutting the injection. But that would also cause the turbo to spin down due to lack of exhaust energy. So it is difficult to imagine how this works without more information. It is not desirable to spin down the turbo if you have to spin it up again when you have to power out of the corner.

I agree with Holm that the MGU-K is much better suited to the purpose of braking.

IMO they will cut ignition and fuel when off throttle, but keep the throttle bodies open if this is allowed. And then use the MGU-K for braking the engine. This cold blowing will keep pumping air though the engine, helping the turbine to keep spinning. Then you can either use the MGU-H to harvest more energy from the turbine, or let the turbine spin freely so you don't have to use as much energy spinning it back up when back on the throttle.

There's so many variables in how to harvest and use the electric energy next year. Pretty exciting.

I am pondering this and it might be the answer. If the engines is running at 10500 rpm and at 21psi boost pressure
(52lbs/min of air flow) and then you were to kill the injectors and ignition the engine at this same rpm would now be flowing around 0 boost and (21lbs/min of air flow with the throttle WO) You would still have to add fuel to keep energy at the turbine and keep its rpm from dropping off due to MGUH load. So at this point you would have to go into ignition retard to power out of the engine and not lose a ton of turbine rpm?

Adding fuel would be a bad idea. When the throttle stays open there's not much to brake the turbine. And it will still spin quite fast due to its inertia. And you could then harvest energy via the MGU-H or just let the turbine spin freely so it has high rpms when you go back on the throttle.

[1158]

Depending on the amount of time off throttle it may be better to not harvest energy via the MGUH and allow the turbo to keep spinning. Ball bearing turbos spin quite freely and for an extended time, I can only imagine how long these turbos will continue to spin for. If the braking zone is limited why collect a little bit of energy from the MGUH only to have to use more energy to spin it back up?

If someone already posted that and I missed it I apologize, thread is moving fast right now lol.

[Holm86]

Depending on the amount of time off throttle it may be better to not harvest energy via the MGUH and allow the turbo to keep spinning. Ball bearing turbos spin quite freely and for an extended time, I can only imagine how long these turbos will continue to spin for. If the braking zone is limited why collect a little bit of energy from the MGUH only to have to use more energy to spin it back up?

If someone already posted that and I missed it I apologize, thread is moving fast right now lol.

I agree with you. Letting it spin would probably be the best thing to do.

That's why you have to leave the throttle wide open. Closing the throttle will only create pressure waves going back through compressor breaking it, wasting energy.

[Holm86]

I also have a theory that drivers will downshift "earlier" next year.

We know the rev limit is 15.000 RPM's. So the engines are build to rev at that speed. But most engines wont rev to over 11.000 RPM's as peak power is at around 10.500 RPM's.

I believe that when drivers are at 10.500 RPM's and gets on the brake they will downshift immediately causing the engine to rev to perhaps close to the 15.000 RPM's. This will help keeping the turbine spinning and I believe it would also let the MGU-K harvest more energy.

[pgfpro]

The reason I was saying you will need fuel is even though the turbo has inertia it doesn't take very long to slow the compressor and turbine wheels down with out air and fuel to energize it. Reason being the compressor side of the turbo takes a lot of energy to keep it spinning due to its nature of compressing air, around 45 turbo shaft HP worth for this engine. Its one large air break when you lose the turbines air and fuel energy.

How many of you guys have experienced a "overly size lots of wheel inertia" turbo on a small engine running a manual transmission and missed a shift. Whats happens??? Your out of boost within a tenth of a second. Even with NLS and anti lag retard you still will kill compressor wheel speed if you don't make the shift clean. Even the best ball bearing turbos of today.

Now if you can decouple the compressor wheel from the turbine wheel it would be a different story, but i thought the rule 5.1.6 keeps this from happening?

5.1.6 Pressure charging may only be effected by the use of a sole single stage compressor linked to a sole single stage exhaust turbine by a shaft assembly parallel to the engine crankshaft and within 25mm of the car centre line. The shaft must be designed so as to ensure that the shaft assembly, the compressor and the turbine always rotate about a common axis and at the same angular velocity, an electrical motor generator (MGU-H) may be directly coupled to it.

On my last post before this one after thinking about it, I don't think adding fuel would do much other then waste fuel.

So I don't know what the gentleman was talking about on the video clip????

[bhall]

Talk is cheap, but it does not answer my question. Why do you have an MGU-H if not for boost limitation and electric power generation?

And some is cheaper than others, right, buddy?

I won't get into the whole MGUH-boost-limitation vs wastegate bit, because it's been done to death here. But, if you think using the MGUH to apply back pressure under engine braking precludes it from generating electricity, that might explain why you still think torque is energy.

[pgfpro]

OK another one of my real life experiences and by all means not bragging rights story's LOL

Pertaining to the MGUH limiting boost on a turbo engine.

A couple of years ago I decided to go after the 4G63 DSM EVOIII 16g turbo record. To do this you don't run a waste gate, in fact you weld the WG flapper shut and let it eat. This eventually kills the turbo. Oh well all in the name of fun.

Well after killing my first turbo I was doing testing and decided to start measuring engine back pressure. Well after about 40hrs on the new turbo I noticed the boost was falling off. So I did a boost leak test and found nothing. So I went to the data log and found out the back pressure was increasing. I was running a lower octane fuel and thought it must be a because of the lower timing that was being ran at the time. So I dumped in some C16 and added timing. The car went faster so i thought I had it all figured out, but the boost didn't increase. Well after about another two more hours of tuning the boost started dropping off even more and back pressure went even higher. So I did another boost leak test and same results nothing. So I thought its time to check the turbo and this is what i found.





As you can see the compressor wheel was hitting the compressor housing. IMO this was reducing compressor wheel speed and thus boost, at the same time increasing exhaust back pressure... So in essence this was being a load type waste-gate??? Just that it was my hillbilly version. LOL

Food for Thought

[wuzak]

I also have a theory that drivers will downshift "earlier" next year.

We know the rev limit is 15.000 RPM's. So the engines are build to rev at that speed. But most engines wont rev to over 11.000 RPM's as peak power is at around 10.500 RPM's.

I believe that when drivers are at 10.500 RPM's and gets on the brake they will downshift immediately causing the engine to rev to perhaps close to the 15.000 RPM's. This will help keeping the turbine spinning and I believe it would also let the MGU-K harvest more energy.

I am not certain that peak power will be at 10,500rpm.

Sure, the peak ICE will be around that, but I'm not so sure the peak MGUH power will be there.

As the RPM increases, the friction does as well. So the power falls off. But since the fuel flow is constant, the air flow requirement will be almost constant and thus the boost willl fall. As the boost falls, less power is used to drive the compressor leaving more power to be recovered by the MGUH/ERSH. The only question is, how much change in the power that can be generated by the turbine as the rpms go up?

[ringo]

Talk is cheap, but it does not answer my question. Why do you have an MGU-H if not for boost limitation and electric power generation?

You have it for electric power generation. It cannot limit boost. It will only retard the time it takes to come up to max boost. This requires power.
You may see this a boost limiting if you use it as a load on the turbine, but in truth it's really a turbine brake more than anything else. So you may interpret this as a limit, but it's not, it is retardation.
It is this retardation that will require a lot of research and testing and fine tuning. You can't instantly cut off boost with this thing. It will have to instantly resist the turbine and then easing up at exactly the right time, with the right level of retardation to maintain a steady turbine speed, all of this happening while back pressure and temperatures increase.

A true boost limiter is a waste gate. It is not a load, it is a relief that reduces mass flow through the turbine. Quite simple and more direct. Very smooth and straight forward.

What we must realize is that the MGUH is no different than the compressor. All it does is compete for turbine power.
But what complicates things is that it shares a mechanical connection to the compressor, it is not a free power turbine like a helicopter engine, where different loads need not run at the same speed.
You will find that what you take off in power for the MGUH may not correspond to what you would like to take off in power for the compressor as these power draws give different outcomes at a certain shaft speed.

There is going to be a tricky balance if the MGUH is used to slow the turbine to control boost.
You can slow the turbine by loading it with the battery or the MGUK, or you can use the battery to drive the MGUH magnetic field in the opposite direction.

Load the turbine, with the MGUH behaving as a resistance. The power drawn must be sent through to the batteries. This easier for boost control because the power is unlimited, The batteries physical limitations for recharge rates will have to tie into your turbine boost control. Very tricky.. If the rate is higher than the power required the MG controller can meter the MGUH loading.

If it's going through the MGUK now, or to something to power a 12v dc load on the car, it must go through the MG control unit. Now this is unlimited, but the truth is it really isn't. The MGUK can give only 120kW to the drivetrain. The unlimited stuff goes back to the batteries. In the event you want control boost and your energy store is full. The MGUH must draw a specific amount of power, to create a specific amount of load on the turbine to give a specific turbine speed to limit boost. You have up to 120kW to do this. If the turbine needs more than 120kW to slow it down, your goose is cooked, you should have shed power off your batteries. Can you predict this? nope! lol

Now using the loading method is quite difficult and i don't think teams will go that route as it's very dependent on what the car is doing on track and the ES state. It's basically playing an all knowing being, a lot of headache to figure out just to control a stupid little compressor. This loading method is less stressful and is more natural but really requires God like awareness of the whole energy system and car to control turbine shaft speeds. Closed looped system with speed sensor tied into the various loads; battery, ancillaries and engine load, will be required.



The other method is attempting to reverse the turbine against exhaust flow.
What i mean like this is to drive the MGUH magnetic field in the opposite direction with the batteries with a certain power lesser than the shaft power. The net torque will be what determines your limited turbine shaft speed. This is most unnatural, as it's a counter action more than a load. However it's easier to do since the battery is isolated from the rest of the loads around the car. The engineer need only look at the unlimited battery to MGUH path as a boost control. Is it worth using battery power to limit boost? Why use your precious energy to control a turbine? Well if what is dumped through the wastegate, is less power than the battery energy required to brake a turbine, then i'd dump it.
If it's less power to use the battery, then i'd consider it but many other factors have to be looked at like temps. response time.