Mercedes Power Unit Hardware & Software

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
roon
roon
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Re: Mercedes Power Unit

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Regarding Mercedes HPP's rumored "vortex exhaust," referenced & suggested by users SparkyAMG & Wazari...
SparkyAMG wrote:A relative of mine spends a lot of time consulting for all of the F1 teams around Luton/Milton Keyes.

The last time I spoke to him about F1 was in the summer, but the development he was most excited about at the time was something Mercedes HPP were trying with their exhaust system for 2017, describing it as 'ground-breaking'.

Because of NDAs he couldn't say any more, and out of respect I didn't push it, but considering he's been in the game a long time (approaching retirement) his excitement was enough to tell me it was a significant development.

I wouldn't take the lack of news about improvements to mean there aren't any.
Wazari wrote:...their rumored high heat retention, vortex exhaust system for 2017? 8)
...I had a go at explaining what this might mean in the Honda Power Unit thread.
roon wrote:...[regarding] the Mercedes "vortex exhaust" rumor. I think what it might be referring to is toroidal vortices, also known as vortex rings. Specifically, they might be inducing vortex rings within the exhaust manifold in order to better entrap heat within each exhaust pulse. Vortex rings are know for their ability to transport heat and gases across long distances, due to their self-contained, self-circulating nature. The specific type of flow I'm referencing is known as poloidal flow, although there are other types.

https://upload.wikimedia.org/wikipedia/ ... lierin.jpg

If a vortex ring can be induced after the exhaust port and made to traverse the length of the manifold before bursting into the turbine inlet, you might minimize heat lost to the manifold's wall. This satisfies the other piece of the rumor—that it was about maximizing heat retention.

https://youtube.com/watch?v=Sj9irzI-Pzw

Initially when I heard "vortex," my mind went to a helical vortex. But helical vortices tend to be open-ended and not self circulating. So, to me, it didn't quite satisfy the heat retention quality. I thought about the concept of self-containment a little more and started visualizing different types of vortical flow. Ring vortices seem to fit the bill.
Below is a small sketch I made illustrating some of the concepts involved, namely:

•a vortex inducer placed just outside the exhaust port on the engine block
•large diameter exhaust piping to accommodate a vortex ring
•a poloidal flow direction facilitating the ring to climb along the pipe interior
•the formation, expansion (or traverse), and subsequent collapse of the vortex ring


Image


Edit- Uploaded better quality photo.
Last edited by roon on 16 Feb 2017, 23:31, edited 1 time in total.

toraabe
toraabe
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Re: Mercedes Power Unit

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FrukostScones
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Re: Mercedes Power Unit

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Haha great, you should run a motorsports themed tatoo parlour :lol:
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Holm86
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Joined: 10 Feb 2010, 03:37
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Re: Mercedes Power Unit

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roon wrote:Regarding Mercedes HPP's rumored "vortex exhaust," referenced & suggested by users SparkyAMG & Wazari...
SparkyAMG wrote:A relative of mine spends a lot of time consulting for all of the F1 teams around Luton/Milton Keyes.

The last time I spoke to him about F1 was in the summer, but the development he was most excited about at the time was something Mercedes HPP were trying with their exhaust system for 2017, describing it as 'ground-breaking'.

Because of NDAs he couldn't say any more, and out of respect I didn't push it, but considering he's been in the game a long time (approaching retirement) his excitement was enough to tell me it was a significant development.

I wouldn't take the lack of news about improvements to mean there aren't any.
Wazari wrote:...their rumored high heat retention, vortex exhaust system for 2017? 8)
...I had a go at explaining what this might mean in the Honda Power Unit thread.
roon wrote:...[regarding] the Mercedes "vortex exhaust" rumor. I think what it might be referring to is toroidal vortices, also known as vortex rings. Specifically, they might be inducing vortex rings within the exhaust manifold in order to better entrap heat within each exhaust pulse. Vortex rings are know for their ability to transport heat and gases across long distances, due to their self-contained, self-circulating nature. The specific type of flow I'm referencing is known as poloidal flow, although there are other types.

https://upload.wikimedia.org/wikipedia/ ... lierin.jpg

If a vortex ring can be induced after the exhaust port and made to traverse the length of the manifold before bursting into the turbine inlet, you might minimize heat lost to the manifold's wall. This satisfies the other piece of the rumor—that it was about maximizing heat retention.

https://youtube.com/watch?v=Sj9irzI-Pzw

Initially when I heard "vortex," my mind went to a helical vortex. But helical vortices tend to be open-ended and not self circulating. So, to me, it didn't quite satisfy the heat retention quality. I thought about the concept of self-containment a little more and started visualizing different types of vortical flow. Ring vortices seem to fit the bill.
Below is a small sketch I made illustrating some of the concepts involved, namely:

•a vortex inducer placed just outside the exhaust port on the engine block
•large diameter exhaust piping to accommodate a vortex ring
•a poloidal flow direction facilitating the ring to climb along the pipe interior
•the formation, expansion (or traverse), and subsequent collapse of the vortex ring


http://i.imgur.com/VwHoo1o.jpg


*Pardon the image quality. I'll be able to upload a better scan tmrw.

That illustration is amazing, not only shows a great explanation of how this could work, but at the same time very artistic. This is brilliant =D> =D> =D>

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turbof1
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Joined: 19 Jul 2012, 21:36
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Re: Mercedes Power Unit

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roon wrote:Regarding Mercedes HPP's rumored "vortex exhaust," referenced & suggested by users SparkyAMG & Wazari...
SparkyAMG wrote:A relative of mine spends a lot of time consulting for all of the F1 teams around Luton/Milton Keyes.

The last time I spoke to him about F1 was in the summer, but the development he was most excited about at the time was something Mercedes HPP were trying with their exhaust system for 2017, describing it as 'ground-breaking'.

Because of NDAs he couldn't say any more, and out of respect I didn't push it, but considering he's been in the game a long time (approaching retirement) his excitement was enough to tell me it was a significant development.

I wouldn't take the lack of news about improvements to mean there aren't any.
Wazari wrote:...their rumored high heat retention, vortex exhaust system for 2017? 8)
...I had a go at explaining what this might mean in the Honda Power Unit thread.
roon wrote:...[regarding] the Mercedes "vortex exhaust" rumor. I think what it might be referring to is toroidal vortices, also known as vortex rings. Specifically, they might be inducing vortex rings within the exhaust manifold in order to better entrap heat within each exhaust pulse. Vortex rings are know for their ability to transport heat and gases across long distances, due to their self-contained, self-circulating nature. The specific type of flow I'm referencing is known as poloidal flow, although there are other types.

https://upload.wikimedia.org/wikipedia/ ... lierin.jpg

If a vortex ring can be induced after the exhaust port and made to traverse the length of the manifold before bursting into the turbine inlet, you might minimize heat lost to the manifold's wall. This satisfies the other piece of the rumor—that it was about maximizing heat retention.

https://youtube.com/watch?v=Sj9irzI-Pzw

Initially when I heard "vortex," my mind went to a helical vortex. But helical vortices tend to be open-ended and not self circulating. So, to me, it didn't quite satisfy the heat retention quality. I thought about the concept of self-containment a little more and started visualizing different types of vortical flow. Ring vortices seem to fit the bill.
Below is a small sketch I made illustrating some of the concepts involved, namely:

•a vortex inducer placed just outside the exhaust port on the engine block
•large diameter exhaust piping to accommodate a vortex ring
•a poloidal flow direction facilitating the ring to climb along the pipe interior
•the formation, expansion (or traverse), and subsequent collapse of the vortex ring


http://i.imgur.com/VwHoo1o.jpg


*Pardon the image quality. I'll be able to upload a better scan tmrw.
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Tommy Cookers
Tommy Cookers
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Re: Mercedes Power Unit

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presumably exhaust pressure pulses anyway have naturally something like this vortical shape ?

heat (being better trapped/transported 'within each exhaust pulse') is energy, to be conserved before use
some quite favourable combination of pressure and temperature
ie not just the hotness stuff that is measured with a thermometer, constrained by insulation, and uniquely suited to cook meat pies

or rather there's an unusually large mass of gas carrying an unusually large flow work potential relative to its temperature
so potentially doing an unusually large amount of flow work on the pistons and turbine
unusual compared to traditional engines that don't dilute their heat with the leaning (extra air mass) that these current engines use
clearly the exhaust gas temperature is much lower in current engines than in previous F1 equivalents
(and exhaust volume is higher)

ok this extra air mass/volume is as usual still going to reach supersonic velocity blowing down following exhaust valve opening ?
so disproportionately (and disadvantageously to energy conservation) having pressure decay despite supporting temperature
that disproportion and disadvantage is still present with the extra air mass ?
Last edited by Tommy Cookers on 16 Feb 2017, 17:02, edited 1 time in total.

ollandos
ollandos
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Joined: 22 May 2014, 07:28

Re: Mercedes Power Unit

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i see the discussion about vortex rings ..and i think if this guns-weapons technolofy is safe for auto-moto engines use...this rings they dont need to much to damage something ...this greate something like ''earthquake'' effect i dont have the data of power of gas on max power but i think 900+hp race engine its not easy to accelarate and brake the exhaust gus ...

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dren
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Re: Mercedes Power Unit

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I wonder how turbulent the flow is after EV blow down, entering the manifold. I'd think for these toroidal vortices to form you'd need a pretty smooth, fast flow in the center. The outlets would need to be circular, too.
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roon
roon
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Re: Mercedes Power Unit

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holm86, turbof1, frukostscones- thank you for the kind words. :)

toraabe- Yes! Just like that. Notice how in that video (~8min mark) how far some of the exhaust gases are transported vertically! The gases not entrained within the vortex ring get gently wafted away horizontally by the wind. This is the advantage I would seek. Maximal entrainment of exhaust gases into a vortex ring, fired down the header, exploding into turbine. It's amazing to me how the inertia & viscosity of a gas can cause it to bind to itself and transport through a similar medium.

I'm in appreciation of how vortex rings manifest at a variety of scales & within a variety of conditions. From the very slow (smoke rings, bubble rings underwater) to the very fast (firearm muzzle blasts). From the very small to the very large (explosion mushroom clouds).

Tommy Cookers- I don't know if a traditional smooth-walled exhaust pathway would necessarily induce toroidal flow. There would only be the relatively small-scale effects of viscosity from gases dragging against the manifold interior, to initiate a large-scale flow pattern. Something needs to trip the flow, something similar in scale to the resultant flow pattern, thus the idea for some type of inducer.

My main concern currently is whether or not vortex rings could survive the pressure differentials seen in the exhaust manifold. It seems like too much of a gradient would override the inertial & viscous forces binding the vortex, causing it to tear apart. How much vacuum, if any (relative to ambient), exists between pulses in a manifold? Said another way: if I fired a vortex cannon in deep space, a ring would likely not form. Pressure differential forces would dominate and the gas would simply want to diffuse radiantly.

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PlatinumZealot
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Re: Mercedes Power Unit

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That is a very cool drawing. Right. u could make money off that. Probably more than being an engineer lol

Ok. I am going to play kanye west here and spoil your party.
I like this discussion but i am going to be that guy who challenges you that the votex ring would not hold up in the exhaust pipe because of drag on the walls as the vortex rotates and expands and the wall curvature and high pressure pulses.
Most "traveling" vortices we see in real life are where the the container is of a scale many times more than the vortex itself. On the other hand In this case where the vortex is so large compared to the container it will "crash" like a wave hitting the rocks as it goes around the turns in the exhaust and exposed to wall drag and changing pressure pulses. And highly tubulent flow will ensue.

I have a way to extend the coverage of the vortices though. Use multiple vortex generation points along the length of the exhaust header. Your exhaust would have multiple steps. After one vortex dies another one is created. is a lot of energy loss but it can work.

And even if the vortices survive all the way to the turbo... They have to crash somewhere.. And that would be into your turbine blades....

It is an interesting discussion. One i would certainly like to continue for the fun of it... Though i think you can achieve temperature retention in better ways.
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shady
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Re: Mercedes Power Unit

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What if we're thinking of the wrong shaped vortex. Instead of toroidal, what if it is more of a 'wave' in a similar vein to the y250.. any helmholtz manifold would surely negate this idea though.. Just a different way to centralize the heat away from the manifold walls.

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ringo
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Re: Mercedes Power Unit

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Why even think about vortex?
The illustration is very good but it looks like more mixing and more heat exchange with the walls of the pipe.
A possible idea is staggered or lapped surface inside the exhaust pipes, to reduce contact time and area of the exhaust gas and the pipes.
Image

similar to this:

Image
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roon
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Re: Mercedes Power Unit

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"Vortex exhaust" was the rumor. Hence the consideration of vortices. Your idea seems like it would induce trapped vortices within the voids (colored blue in your drawing), so you might be on the right track while also satisfying the wording of the rumor. 8)

Tommy Cookers
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Re: Mercedes Power Unit

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what I always feel like saying seeing the topic (or myth ?), regarding the implied substantial loss of heat energy through the exhaust piping is .....

the exhaust gas is at a mean pressure of 5 bar, moving at a mean velocity of 300 mph in a plain pipe
if this situation has significant heat loss why do we ever need 'radiators' ?
ie devices whose surface area/transit time product is several orders of magnitude greater

my gut guesstimate is that the energy loss preventable by insulation is less than 1%
energy is wasted by irreversibity of (supersonic) port blowdown and manifold transition processes - this cannot be saved even by infinite insulation
if insulation significantly reduced energy loss why would we do it in an NA race application ?
exhaust energy loss and consequent pressure loss would be beneficial to NA

just saying .......

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ringo
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Re: Mercedes Power Unit

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roon wrote:"Vortex exhaust" was the rumor. Hence the consideration of vortices. Your idea seems like it would induce trapped vortices within the voids (colored blue in your drawing), so you might be on the right track while also satisfying the wording of the rumor. 8)
Yes, i forgot to mention the trapped vortex acting as a thermal barrier. thanks!
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