Tube for thought

[mmattockx]

OK I refreshed my memory (it was blearaly correct).

An ideal (potential flow) vortex has a velocity profiles of 1/R (R is distance from the center) so even in practice it gets pretty high velocity (lowering the pressure) right at the center. V can't go to infinity because viscosity starts to come into play.

Vortexes are a fundamental part of fluid dynamics and is what is used to explain circulation which is what generates Lift.

Those aircraft wing tip vortices have a lot of energy in them just generated by the spanwise flow, rounding the tips of the wings.

I see what you are talking about, you are thinking a vorex like you can get when dumping water out of a bottle and you put a spin to it. I was thinking more just spiral flow. I don't think you could generate the forces required in the intake to get air to behave in the same manner. The forces generating wingtip vortices are much higher than what OP is working with. BTW, the 1% velocity increase I calculated comes from ~8 degrees of angle on the spiral flow. While I don't think the ridges in OP will ever do much to redirect the flow, 8 degrees is probably possible with some vanes across the stack opening. I don't know if it would achieve anything of note, but it might be possible.

F1 racing seems to be at the leading edge of all this.

That's because they have the money to hire the smartest people and buy the best equipment and it matters to them because they are chasing such ridiculously small margins.

wow. this is more reaction then i ever thought. And no one has mentioned its basically a TRUMPet. Even better. So presuming i was a rich person with a well sorted 1000S superbike. It be ok to go get some plastic 3D stacks made and see if any effect. Trouble is im not rich.

A trumpet has a much different function than a velocity stack, though. As for the 3D printing, my local library has a printer that can be used for a pretty nominal fee. Check around your area and see if there is any sort of maker's group, technical school or similar that offers a cheap 3D printing option. I bet even Shapeways wouldn't be prohibitively expensive for a set: https://www.shapeways.com/

I bet it got him loads of women though.

And we all know that is the true measure of an idea!


Mark

[posplayr]

I see what you are talking about, you are thinking a vorex like you can get when dumping water out of a bottle and you put a spin to it. I was thinking more just spiral flow. I don't think you could generate the forces required in the intake to get air to behave in the same manner. The forces generating wingtip vortices are much higher than what OP is working with. BTW, the 1% velocity increase I calculated comes from ~8 degrees of angle on the spiral flow. While I don't think the ridges in OP will ever do much to redirect the flow, 8 degrees is probably possible with some vanes across the stack opening. I don't know if it would achieve anything of note, but it might be possible.


Mark

You can look up the measure of Circulation in a vortex,but is probably some alfa*CONSTANT where constant relates to the integral of the 1/R function is 2 or 3 dimensions. Alfa relates to total intensity of circulation.

Regardless of alfa, 1/R==> infinity as R==>0 meaning velocity increases to the limit of the viscous shear forces at the center of the vortex regardless of alfa. Your formula just doesn't apply. If you want to calculate the peak velocity calculate the maximum velocity supported by the viscous shear forces.

The principle clearly works, the only question is only how well it is implemented. We know for example that a vortices are created in a number of ways in nature; water going down a drain, wind devils in the desert, tornados, hurricanes.

All of these are due to Coriolis forces acting on a fluid. Recall Coriolis forces are forces on a body due to linear velocity in a rotating frame. In the rotating frame of the Earth, that means that any rising or lowering (with respect to the center of the earth)will cause a Coriolis force (and without checking) is apparently oriented along the (vertical) velocity vector.

If water going down a drain, can form a vortex where the pressure distribution is represented by the depression in the surface, I'm not sure it would be that hard to generate a vortex of some magnitude which will in theory have the limit of velocity always at it's center.

[Blue Falcon]

You can look up the measure of Circulation in a vortex,but is probably some alfa*CONSTANT where constant relates to the integral of the 1/R function is 2 or 3 dimensions. Alfa relates to total intensity of circulation.

Regardless of alfa, 1/R==> infinity as R==>0 meaning velocity increases to the limit of the viscous shear forces at the center of the vortex regardless of alfa. Your formula just doesn't apply. If you want to calculate the peak velocity calculate the maximum velocity supported by the viscous shear forces.

The principle clearly works, the only question is only how well it is implemented. We know for example that a vortices are created in a number of ways in nature; water going down a drain, wind devils in the desert, tornados, hurricanes.

All of these are due to Coriolis forces acting on a fluid. Recall Coriolis forces are forces on a body due to linear velocity in a rotating frame. In the rotating frame of the Earth, that means that any rising or lowering (with respect to the center of the earth)will cause a Coriolis force (and without checking) is apparently oriented along the (vertical) velocity vector.

If water going down a drain, can form a vortex where the pressure distribution is represented by the depression in the surface, I'm not sure it would be that hard to generate a vortex of some magnitude which will in theory have the limit of velocity always at it's center.

too much to multi-quote.....with all us smarty-pants have said... the real questions... in non-Mensa speak

Cost/Gain

1. Would there be any significant increase in performance just by adding the horn.
A. You would have to modify so much of the entire intake to truly see any measurable increase that the cost would drastically outweigh the gain - daily riders

2. Cool factor?
A. Yes, would have a cool factor - marketing/fancy color/cool name/pod combo

3. Who could use it?
A. Hard core racers - would need a team to make mods and fine tune everything.

4. If you were to make it would it sell?
A. Go back to 2... people will buy anything with the right marketing. Just don't make any outrageous claims. Here is a tag line you could use and be OK.

"Using the same technology that Formula 1 engineers use in their engines"

With all we have said.... great idea, try it out, don't expect any measurable results....and make it look cool.

[posplayr]

too much to multi-quote.....with all us smarty-pants have said... the real questions... in non-Mensa speak

Cost/Gain

1. Would there be any significant increase in performance just by adding the horn.
A. You would have to modify so much of the entire intake to truly see any measurable increase that the cost would drastically outweigh the gain - daily riders

2. Cool factor?
A. Yes, would have a cool factor - marketing/fancy color/cool name/pod combo

3. Who could use it?
A. Hard core racers - would need a team to make mods and fine tune everything.

4. If you were to make it would it sell?
A. Go back to 2... people will buy anything with the right marketing. Just don't make any outrageous claims. Here is a tag line you could use and be OK.

"Using the same technology that Formula 1 engineers use in their engines"

With all we have said.... great idea, try it out, don't expect any measurable results....and make it look cool.

Yes the biggest factors would be how "pretty" it would be.

[sharpy]

And then theres always that claim. "As seen on TV" or even better "Modeled on US engineers thoughts connected to the Space programme and made in Australia" Space claim is that one person does live in Florida. LOL

[GregT]

You do realise that if the coriolis force was to be of any use, you'd have to make them with the twist going one way for the Northern hemisphere - and the opposite way for us down here....

Personally, I suspect that it's simply going to give a deeper, more turbulent boundary layer. This might be of use if the intake of the carb was too big for the application.

[posplayr]

You do realise that if the coriolis force was to be of any use, you'd have to make them with the twist going one way for the Northern hemisphere - and the opposite way for us down here....

Personally, I suspect that it's simply going to give a deeper, more turbulent boundary layer. This might be of use if the intake of the carb was too big for the application.

EDIT:

In physics, the Coriolis force is an inertial force (also called a fictitious force)^[1] that acts on objects that are in motion relative to a rotating reference frame. In a reference frame with clockwise rotation, the force acts to the left of the motion of the object. In one with anticlockwise rotation, the force acts to the right. Though recognized previously by others, the mathematical expression for the Coriolis force appeared in an 1835 paper by French scientist Gaspard-Gustave de Coriolis, in connection with the theory of water wheels. Early in the 20th century, the term Coriolis force began to be used in connection with meteorology. Deflection of an object due to the Coriolis force is called the 'Coriolis effect'.

https://en.wikipedia.org/wiki/Coriolis_force

Not sure you really understand what a Coriolis force is. It is ANY linear motion in a rotating frame, not just the earth's rotating frame. I brought up naturally occurring vortices to demonstrate that significant forces can get generated with very low angular rate vectors(i.e. earth rate).

Look at equation 3.10 on page 31

the +w X m V term is the cross product of an angular momentum vector with a velocity vector.

6DOF_EQ_Motion.jpg

http://www.dtic.mil/dtic/tr/fulltext/u2/283911.pdf

Sorry for the dated reference; first one to come up.

[Blue Falcon]

EDIT:

https://en.wikipedia.org/wiki/Coriolis_force

Not sure you really understand what a Coriolis force is. It is ANY linear motion in a rotating frame, not just the earth's rotating frame. I brought up naturally occurring vortices to demonstrate that significant forces can get generated with very low angular rate vectors(i.e. earth rate).

Look at equation 3.10 on page 31

the +w X m V term is the cross product of an angular momentum vector with a velocity vector.

[ATTACH=CONFIG]49946[/ATTACH]

http://www.dtic.mil/dtic/tr/fulltext/u2/283911.pdf

Sorry for the dated reference; first one to come up.

oh for pete's sake.....ram air the dam carbs...build and intake that takes air from the front of the bike... let's put pin wheels on it to tell us when we are up to speed and have a control valve that opens at speed...lets also put in an electrostatic filter that zaps any contaminants and ionizes the air, magnetic fuel rail, and a midget on a tricycle with a tool set... lets add so many metering/control devices we add 30lbs to the bike and offset any gain we would have received.....

Make the horn shiny and with a cool name....ooooo shiny.

[posplayr]

oh for pete's sake.....ram air the dam carbs...build and intake that takes air from the front of the bike... let's put pin wheels on it to tell us when we are up to speed and have a control valve that opens at speed...lets also put in an electrostatic filter that zaps any contaminants and ionizes the air, magnetic fuel rail, and a midget on a tricycle with a tool set... lets add so many metering/control devices we add 30lbs to the bike and offset any gain we would have received.....

Make the horn shiny and with a cool name....ooooo shiny.

I figured you would have a overt inclination toward complexity, while everything in discussion is the most fundamental results of physics(i.e. symplicity).

I already told you the best answer, it was your dimpled helmet. Did you mention anything related to wind resistance anywhere in you childish diatribe?

[Blue Falcon]

I figured you would have a overt inclination toward complexity, while everything in discussion is the most fundamental results of physics(i.e. symplicity).

I already told you the best answer, it was your dimpled helmet. Did you mention anything related to wind resistance anywhere in you childish diatribe?

no diatribe...but after years of working in the engineering field.. I have learned a few things

1. Law of Parsimony
2. Name brand college grad engineers love SS2CPWNBT "simple solutions to complex problems will not be tolerated"... refer to rule 1
3. Closed minded people never get anything accomplished
4. Black box theory of troubleshooting
5. Engineers never can appreciate sarcasm at any level

There is a reason one of the best helmet manufacturers out there doesn't make the dimpled helmet anymore lol.

Brainstorming is great... but too many hands in the cookie jar.... just never know who didn't wash their hands.

We just all over complicated it...we reinvented the wheel on this one. New and Improved is just the same as the old...little shinier and with a cool name. lol

[posplayr]

no diatribe...but after years of working in the engineering field.. I have learned a few things

1. Law of Parsimony
2. Name brand college grad engineers love SS2CPWNBT "simple solutions to complex problems will not be tolerated"... refer to rule 1
3. Closed minded people never get anything accomplished
4. Black box theory of troubleshooting
5. Engineers never can appreciate sarcasm at any level

There is a reason one of the best helmet manufacturers out there doesn't make the dimpled helmet anymore lol.

Brainstorming is great... but too many hands in the cookie jar.... just never know who didn't wash their hands.

We just all over complicated it...we reinvented the wheel on this one. New and Improved is just the same as the old...little shinier and with a cool name. lol

I can appreciate your list, but I'm pretty sure your message is NOT coming across. I think you have so many points that it is not making any of them clear.

[Blue Falcon]

I can appreciate your list, but I'm pretty sure your message is NOT coming across. I think you have so many points that it is not making any of them clear.

we all took his simple design and kept throwing equations/design/suggestions/more suggestions/more physics/more design and overcomplicated it when in turn the original horn in it's simplest form is probably the best out of all this. It's like that engineering movie they play... caveman thinks of a wheel, makes the wheel, sells the wheel, another guy comes along takes the caveman into his business, teams of engineers change/design/etc etc etc the original wheel and after all of the testing/prototypes/marketing etc... they come out with the same exact wheel that the original caveman had and present it like it is brand new... it was as good as it needed to be from the beginning.

Fun to banter and throw around our polysyllabic words and hyphenated named theories.... but in the end... we all just overcomplicated it.

conclusion... ignore everything we said... make it how you want too make it.. just make it shiny( this is a metaphor ) with a cool name.

[posplayr]

we all took his simple design and kept throwing equations/design/suggestions/more suggestions/more physics/more design and overcomplicated it when in turn the original horn in it's simplest form is probably the best out of all this. It's like that engineering movie they play... caveman thinks of a wheel, makes the wheel, sells the wheel, another guy comes along takes the caveman into his business, teams of engineers change/design/etc etc etc the original wheel and after all of the testing/prototypes/marketing etc... they come out with the same exact wheel that the original caveman had and present it like it is brand new... it was as good as it needed to be from the beginning.

Fun to banter and throw around our polysyllabic words and hyphenated named theories.... but in the end... we all just overcomplicated it.

conclusion... ignore everything we said... make it how you want too make it.. just make it shiny( this is a metaphor ) with a cool name.

Unfortunately what you do not realize is that the design is based on such a fundamental principle (as evidenced by the discussion) that it can't help but work. What you see as complexity is actually simplicity. I even posted the single equation that describes it; that is the essence of simplicity.

[Blue Falcon]

Unfortunately what you do not realize is that the design is based on such a fundamental principle (as evidenced by the discussion) that it can't help but work. What you see as complexity is actually simplicity. I even posted the single equation that describes it; that is the essence of simplicity.

Break it down simpler... suck, bang, blow.... we are just discussing how it sucks.

[posplayr]

Break it down simpler... suck, bang, blow.... we are just discussing how it sucks.

Actually you are more of a passive observer to the technical discussion.