Nope, bore and stroke is pretty much standardized. And we have sufficient technical argument for the new engines to have a great sound. No reason at all why the racing should be any less thrilling than today.Ian P. wrote:.. 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.
I'm pretty sure you are wrong. The petrol turbos will not have the catalytic soot filters required by the LeMans diesels. That is the main reason for the quietness of the diesels. Noise accounts for less than 0.1% of the energy that exits the tail pipes. So there is no reason why they cannot engineer an absolutely impressive sound. Very prominent F1 engineers have come out with predictions that the sound of the V6 turbos will be thrilling and I believe those people to know their sh!t.RaceFaceXC wrote:I have a feeling that the turbo engines will be much quieter, especially after some time to develop and refine them. The turbine housing itself, acts like a muffler and extracts much of the energy that would otherwise make noise. Extracting the most possible energy from the wasted exhaust gases would have to result in less energy exiting the tailpipe and thus less noise. This is my theory, anyway. A little bit of data to support my theory is the Audi LMP diesels. they are eerily quiet on the throttle and absolutely silent on decel. so quiet that I could hear the air rushing over the vehicle and the tires working over the sound of the engine.
Anyone have any insight on my theory one way or another?
Most of the f1 engine teams have been moved to other things. Its much easier to refine and existing design then to start with a clean sheet.Paul wrote:Trying to find and exploit loopholes to add minuscule amounts of performance to a "frozen" engine can cost a lot of money. Potentially more than that required to develop/adapt entirely new devices. Depends, of course, on how far you want to go.
I wasn't trying to make the argument that turbocharged engines are quiet, or quieter than N/A engines.agip wrote:If you think this is quiet, then yes...
[youtube]http://www.youtube.com/watch?v=pOjaxYlKdSQ[youtube]
[youtube]http://www.youtube.com/watch?v=C3ypmT3oFlw[youtube]
Why would a catalytic soot filter create such a decrease in volume? I am not a engineer, so I do not understand how it could reduce the volume level without inhibiting exhaust velocity and hence performance.WhiteBlue wrote:I'm pretty sure you are wrong. The petrol turbos will not have the catalytic soot filters required by the LeMans diesels. That is the main reason for the quietness of the diesels. Noise accounts for less than 0.1% of the energy that exits the tail pipes. So there is no reason why they cannot engineer an absolutely impressive sound. Very prominent F1 engineers have come out with predictions that the sound of the V6 turbos will be thrilling and I believe those people to know their sh!t.
It's not only about heat. You have a pressure drop across the turbine stage (and not that small), as well.amouzouris wrote:what the turbo is doing is making the engine more efficient using the wasted HEAT energy...sound has nothing to do with it..
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?RaceFaceXC wrote: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 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".amouzouris wrote: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..
Why is heat generated when you try to reduce the sound level?hardingfv32 wrote:
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
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.noname wrote:It's not only about heat. You have a pressure drop across the turbine stage (and not that small), as well.amouzouris wrote:what the turbo is doing is making the engine more efficient using the wasted HEAT energy...sound has nothing to do with it..
The way you are mixing exhaust gases with ambient has significant impact on noise. Chevron nozzle used in the jet engines are good example.
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?amouzouris wrote: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..
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.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.