Formula One 1.6l V6 turbo engine formula

[hardingfv32]

i thought of noise being a product of wasted energy, and the noise itself being a small amount of energy but the processes that create the noise being the source of much larger amounts of energy. so without a muffler or other noise abating technology, how would the sound be reduced so drastically without the energy wasting processes being avoided in the first place?

I think the sound is a product of the fluctuation in flow, valve activity, turbulence, etc. Heat is generated when you try to reduce the sound level. Could the turbos reduce the fluctuations and also use the heat generated from the effect?

Brian

[RaceFaceXC]

an engine will be a certain percentage efficient...another percentage will be wasted as heat and another percentage as sound...what the turbo is doing is making the engine more efficient using the wasted HEAT energy...sound has nothing to do with it..

I understand how a turbine extracts energy from an expanding gas fairly well... And that the turbine gets very little or maybe no energy from the sound being generated. This is not really what I was inquiring about. I was asking, more specifically if a turbine and associated parts (housing, blades, etc) would result in a lower volume (as in dB) out of the "tailpipe".

I think the sound is a product of the fluctuation in flow, valve activity, turbulence, etc. Heat is generated when you try to reduce the sound level. Could the turbos reduce the fluctuations and also use the heat generated from the effect?

Brian

Why is heat generated when you try to reduce the sound level?

what the turbo is doing is making the engine more efficient using the wasted HEAT energy...sound has nothing to do with it..

It's not only about heat. You have a pressure drop across the turbine stage (and not that small), as well.

The way you are mixing exhaust gases with ambient has significant impact on noise. Chevron nozzle used in the jet engines are good example.

I have a well rounded background in how sound behaves when it applies to jet exhaust. the chevron nozzle design was developed to enhance mixing of hot, high velocity gas with cold low velocity gas while resulting in a lower turbulent flow and less energy being converted into audible sound. I actually did research and wrote a paper on this exact subject.

The pressure drop across the turbine results in lower velocity and lower temp. gas. this should also result in less noise, no?

an engine will be a certain percentage efficient...another percentage will be wasted as heat and another percentage as sound...what the turbo is doing is making the engine more efficient using the wasted HEAT energy...sound has nothing to do with it..

But the sound comes from the wasted energy in the hot, fast moving exhaust gases. So reducing the energy in the gases should result in less noise, no?

I can't help but feel like this discussion is turning into an argument, but I had no intention of that. I just wanted to understand why the engine design that is the subject of this thread would be so loud and spectacular if the engineers were trying to extract the most amount of energy possible from the very thing that is creating the noise in the first place.

P.S. - does anyone have any idea about where I could find out more about the turbo diesel systems in ALMS (specifically the Audi). I cannot believe that a soot catalytic converter would be responsible for virtually silencing such a powerful machine. Im not saying that is untrue, I just do not understand how it could be.

[WhiteBlue]

Wikipedia

Diesel exhaust contains relatively high levels of particulate matter (soot), consisting in large part of elemental carbon. Catalytic converters cannot clean up elemental carbon, though they do remove up to 90 percent of the soluble organic fraction[citation needed], so particulates are cleaned up by a soot trap or diesel particulate filter (DPF). A DPF consists of a Cordierite or Silicon Carbide substrate with a geometry that forces the exhaust flow through the substrate walls, leaving behind trapped soot particles. As the amount of soot trapped on the DPF increases, so does the back pressure in the exhaust system. Periodic regenerations (high temperature excursions) are required to initiate combustion of the trapped soot and thereby reducing the exhaust back pressure. The amount of soot loaded on the DPF prior to regeneration may also be limited to prevent extreme exotherms from damaging the trap during regeneration.

By considering the bolded part you may appreciate that filtering the exhaust through a ceramic block with very fine pores the sound will also be reduced considerably.



The diesel particulate filters tuck in either side of the engine and behind the turbos. Peugeot 908 Spa 2011.

[pgfpro]

From my experience on the turbo cars I have built and tuned on the turbo does reduce some of the sound when running a full exhaust system.

But on my last turbo Talon I had a 3" exhaust pipe that was only two feet long. This was extremely loud.

My 1.6L turbo Del Sol with a up pipe.


The same with a friends Nissan SR20 with a rear mount turbo running a 3" dia. 1 1/2 foot exhaust dump pipe. We thought it would be about as loud as it was when it had a performance header and full exhaust. But it turned out to much louder. All three of these cars could be heard from a long ways away when going down the track.

So I would guess that the F1 new setups will be very loud with very short post turbo exhaust?

Now whats strange on my new 2.0L 800+ HP turbo compound setup the exhaust notes is a lot less aggressive and sounds more like a jet engine. But it sure is a lot nicer to drive on the streets.


EDIT:
One more thing I thought of is when I owned a RX7 Turbo II I remove the CAT for flow reasons and the exhaust note became a lot more louder.

[Pierce89]

First we had Engines, then they added KERS. Costs go up .... or down ...???
End result, not down.
Now they are talking about a whole new concept. Yes the engine itself is potentially simpler and less expensive, but the KERS, HERS etc. sure as heck isn't going to be free or cheap.
But Wait .... it doesn't stop there.
The advent of the fluel flow limitation at 100kg/Hr, will only reward those that can generate the highest thermal efficiency out of the engine. This aspect alone will have an enormous cost. The benefit will go to those that get it right.
From my calcs, the HP will be limited (based on fuel flow) to 640 BHP for an overall efficiency of 40% from 10,500 rpm to whatever you want to shift at (under 15,000). Bump this up to 45% and you gain 80 BHP.
This is competition at the highest level. The manufacturers will turm themselves inside out to squeeze that last fraction of a percent. You can't override this with turbo boost because of the fuel flow limit.
We will see different bore and stroke engines, different max revs, the boost profiles will all be the same, they will sound like crap, sorry sheeeeooot-pop and being a smaller overall package, the aerodynamics will be even more important than todays cars.
Don't get me completely wrong, it is going to be absolutely fascinating to see this come together. Good racing, I doubt it.

I agree with virtually every single word of this. These powertrains will be extremely fascinating to people like us, but we're a tiny tiny bit of the people F1 wants to reach. To regular people, the only difference they'll notice, is the cars don't have a banshee wail like they used to.
But hey, if they're willing to spend all that money to fascinate a few of us gearheads, then I won't complain.

[hardingfv32]

Why is heat generated when you try to reduce the sound level?

I think because you are attempting to stop or kill the sound waves.

Brian

[machin]

The actual energy in sound is incredibly low.... one example Ive been told in the past is that there is more energy associated with the heat generated by stamping your feet than there is energy in the sound you can create blowing into a trumpet....

[xpensive]

The actual energy in sound is incredibly low.... one example Ive been told in the past is that there is more energy associated with the heat generated by stamping your feet than there is energy in the sound you can create blowing into a trumpet....

Joshua was of a somewhat different opinion.

[hardingfv32]

How do the pressure waves and sound relate?

Maybe it is the pressure waves moving the control chamber wall. Internal friction in the walls?

Brian

[strad]

are not sound waves a form of pressure wave?

[xpensive]

Wiki is your friend, enter Sound power!

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

[WhiteBlue]

All this sound discussion is is pointless when you consider that less than 1% of the engine power will go into sound energy.

Sure enough F1 fans want loud engines and the engineers at the manufacturers are aware of that and will engineer the sound impressively. This is mainly a question of how you dampen or even amplify the sound by suitable channelling. The engineers do it all the time for road cars, but with other objectives.

Please believe me that petrol turbos will be very much louder than the LeMans diesels. Diesels have no choice in how they design the sound channels. The channel geometry is given by the particulate filter technology and it happens to make the exhaust quiet. This will not happen to the 2014 F1 petrol turbo engines!!!

The FiA would have loved turbo diesel engines because they have even higher efficiency than the new petrol turbos will have. But they ware aware of the sound issue and that killed the diesel for F1.

[strad]

they weren't that quiet in the 80s...why do we think they will be this time?

[Shaddock]

I wonder. With the ban on OT-EBD maps now; how possible would it be; when these 1.6L engines come out; to work around that?

Would it be possible for example; to substitute it with the pressure blow-off valve?

Very unlikely in my view. Waste gates may not even exist on those designs because any surplus of turbine power over the compressor demand would be sapped by the MGUH. The MGUH is supposed to contribute 90 kW to the motive power. If they have a waste gate at all it would merely be a safety feature.

I don't see a reason why the teams wouldn't put an external wastegate on the turbos. How they configue the actuator is the clever part. There has to be a blow off or recirculating valve on the cold side, a blow off would give a very nice sound on upshifts.

[WhiteBlue]

I don't see a reason why the teams wouldn't put an external wastegate on the turbos. How they configue the actuator is the clever part. There has to be a blow off or recirculating valve on the cold side, a blow off would give a very nice sound on upshifts.

I don't understand how you see the design of the system. In my view the MGUH will compensate all the power/torque that is demanded/not needed by the compressor. It means that the MGUH in motor mode will spool up the compressor to avoid lag. It also means that the MGUH as a generator will place additional load on the turbine when the compressor does not demand enough power/torque from the turbine to provide the cylinder load. This will all be controlled in closed loop by the power electronics of the MGUH. There will not be an over power situation from the turbine side which will require the regular opening of a waste gate unless they design the system in a way that it cannot cope automatically. So the waste gate will be entirely a safety feature for cases of malfunctions in the system. Every operation of the waste gate reduces the efficiency of the power train. So they will aim to operate it as little as possible.