lets talk baffle design

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hushhush
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lets talk baffle design

Post by hushhush »

Okay first this is my point of view, and is how I see different baffles. Almost all baffles more than a few years old are related be it kissing cousins.

First we start with the most basic baffle, the flat washer. It works by just acting as a restriction to flow and uses a spacer to keep spacing. It is not the most effective but it works. The next step in the line from a flat washer is a simple M baffle, which I see as the same as a cone baffle. The cone/M baffle just uses different angles to make the gas work harder to get out of the suppressor. In a flat baffle the gas has to make no more than a 90 degree turn to get out, in a cone/m baffle it can needs to make as much as a 180 degree turn to get out. But the M baffle is just a flat baffle that is not flat, it works once again just by being a restriction to flow.

The difference between a cone baffle and a M baffle is simply the spacer, or lack of spacer and to some extent the angle and length of the cone. A M baffle has the spacer attached to form the M shape in cross section. A cone baffle has no attached spacer and some times no spacer when it is welded to the tube. Now we will ignore stepped cone and M baffles right now.

The next step in baffle design is the K. The K baffle is really 2 parts the baffle face, which depending on the exact baffle is nothing more than a flat or cone/M baffle. Some K's have a raised "cone" around the bullet passage, at least the more effective ones. Which is where where get some baffle kissing going on. A M baffle is more effective than a flat baffle due to the extra turning the gasses have to do, as a K with the "cone" is more effective for the same reason. Now some K's and some cone/M baffles have a scallop cut to direct gasses across the bore bath, once again some kissing cousin stuff.

Now the K has a second part, the rear cone, which also acts as the spacer. Now the spacer is shaped at an angle that is supposed to help the gas expand out of the bore path, but it is a spacer. We get by the design a coaxial chamber out side the cone to help slow the gasses escaping, which is helped by the scallop cut directing some gasses out side the cone. If we removed the cone from a K baffle it would be a flat or cone/M baffle that would need a spacer. Now we have to ignore the extra cuts, bevels and holes that work the gasses here because we are keeping it simple. Now the next step in my mind is the omega ( O for short ).

The omega ( O ) is also nothing more than a K baffle with a different spacer. The K has an angled spacer, the O has a straight spacer. But the spacer on each does that same thing it creates a coaxial chamber and acts a the spacer. Once again if you removed the spacer from the back of a O baffle it is just a cone/m baffle. Now once again we are leaving out any step cutting.

Now we get into mono cores along the lines of the prodigy and mite. They are basicly flat baffles set at an angle to the bore, this directs some gasses across the bore to slow them down and make the work harder to escape. But if you look at it like this a angled flat baffle works the same was a M baffle it makes the gasses have to turn more than 90 degrees to get out, just with the added benefit of lots of cross flow. Now we can get cross flow by angling baffles, scallop cuts, and extra holes drilled off center, the angled baffle just works well for this.

Now I know there are other baffle designs but the ones listed above are some of the most common, and they all work by the same basic ideas. Or at least each design ties in with another one, one way or another. I also know some of the "newer" designs are just more of a tuning of an older design, aka tirant.

I think the next big step in design will be way out side the box, and will make a huge jump. It will also be based more on fluid flow dynamics than reworking all of the above, you can only tweak existing designs so much.

The one design i would like to try would be a mono core that was cross drilled using a step/uni bit. This would force the gasses to go off to one side, plus would contain some stepping of the "baffle" walls, and force the gasses to do more than a 90 degree turn to get out. It would look kind of like this in cross section ^V^V^V^V^ similar to an angled flat while a current cross drilled looks like l ll ll ll ll ll l , or a flat baffle.

Okay feel free to tear me apart.
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delta9mda
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Re: lets talk baffle design

Post by delta9mda »

consider yourself torn :evil:
NP
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PaulNoiseLess
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Re: lets talk baffle design

Post by PaulNoiseLess »

Hi,

Yes, what a fucking life !. Baffles are like women: They all look different but, at the end of the day, they are all the same … No matter if they are S or K or M or … they are women and do have similar behavior (plus/minus peanuts).

God safe the Cones !

Best,

Paul
The future is not waiting for us, it is waiting within us ...
hushhush
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Re: lets talk baffle design

Post by hushhush »

First I do understand that each baffle type works better than some other, depending on volume, length, pressure, bore diameter etc etc. I never said they are all the same, but they all have features that are similar. And I dont mean they all have a face and a spacer.

Also I know that different holes in different places, plus spacing can make a huge difference. It is just as simple as all the baffles I mentioned are similar in many respects.
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LavaRed
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Re: lets talk baffle design

Post by LavaRed »

You forgot parabolic baffles, which do reflect and re-focus some of the flow and sound that they receive, when properly made. Those already contemplate some alternative concept of flow dynamics, as well as thermodynamics.

What many people fail to realize is that a single baffle acts in 2 stages: A) Flow obstruction B) Gas expansion.

Now for the first stage, the most efficient method to achieve this is to force the gas to do the most work, i.e., shed the most energy, in order to escape, while at the same time reducing its velocity. This process may or may not change the volume of the gas, but heat transfer does occur, and the pressure of the flow necessarily increases. The second stage, on the other hand, is nothing more than a nozzle, where the adiabatic expansion of the gas occurs. The gas flow loses pressure and consequently it's velocity increases. The most efficient second stages are those that cause the gas to expand the fastest, which may be helped mainly by baffle geometry and texture.

So, the most efficient second stage of a baffle is naturally a parabola. Expansion could be further assisted by finding the proper function for each bore/pressure ratio, and also perhaps by scalloping the inner walls of the baffle to assist ariflow, such as in golf-balls and some modern precision bullets.

On the other hand, there is no set way yet to configure the first stage. There could be a myriad ways, including coaxial chambers.

To be honest I firmly believe it is as much an issue of thermodynamics as well as flow dynamics.

What is key, however, is that a baffle should aim to reduce the velocity, but more importantly, the pressure, of the gas flow, given that sound pressure level is directly a function of the exit-flow's pressure level.

More to be said on this subject.

Thank you for listening,
LavaRed
"There are no stupid questions, only stupid people". -MAJ MALFUNCTION
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Bowen1911
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Re: lets talk baffle design

Post by Bowen1911 »

I think if your baffles had micro-groves all over it, it would give more surface area for the viscosity of air to slow itself down, and possibly give some increase in quiet-downy-ness


maybe the next big idea is a vacuum that sucks the gas out behind the bullet eliminating muzzle blast 100% :idea:
"I notice that everybody that is pro-abortion already has been born."
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http://www.youtube.com/watch?v=mq-XG3tn7s0
Historian
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Re: lets talk baffle design

Post by Historian »

Most impressive precis of the various designs.

As any good designer you first have laid out the parameters attendant
the various successful designs up to the present with their reifications.
This is necessary prior the next break through.

Consider in extremum the attenuation of the
explosive sound by say the magnificent exhaust system of an Aston Martin Vantage.
Its success is best illustrated when you decide to stomp down on the accelerator
and the electronics allow the full 'throaty roar' to optimize acceleration by removing
restrictions. Worthy of an harmonious angels chorus of 1911-A1's parading by.

"I heard your bloody arrival way before you came into sight!." :)

What and how were the gases directed and redirected in the quiet mode?

What aspects of the chamber configurations and geometries tuned the turbulences?

Can a mirror metaphor of Nitro Injection be applied for attenuation?

For example take the Venturi from a liquid reserve along the lines of baffles
with anechoic shapes, in the vein of the individual exhaust
tubes on the 1934 Mercedes Benz Count Trossi SSK.
<< http://www.topspeed.com/cars/mercedes/1 ... 46695.html >>

The breakthrough to the "100 Db" suppressor will be made by the next generation of John Brownings/ Gene Stoners on this forum
with the field experience, research passion, and demonstrated mental and technical acuity so abundantly demonstrated daily
on this forum.

What a wonderful band of brothers.
maddyn
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Re: lets talk baffle design

Post by maddyn »

Long time lurker, no time poster... but I really liked the way this discussion was going, especially Historian's post. I totally understand that suppressor design is mainly fluid dynamics, but I had always thought it was more acoustic design/modification before I started reading here. Having had a little experience and research into designing rooms for acoustical tuning/modification, I had thought the best suppressor would be the one that took into account the sound frequency that existed at the muzzle and run it through a series of chambers to strip off and modify certain sound frequencies... which when you really look at it, is what fluid dynamics is doing. Just slowing down the gasses to a different "frequency" just as you would design your room to slow down or trap certain frequencies so the full spectrum reaches your ears at the same time.

Anyway just food for thought, and my ramblings worth about .02
Historian
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Re: lets talk baffle design

Post by Historian »

maddyn wrote:Long time lurker, no time poster... but I really liked the way this discussion was going, especially Historian's post. I totally understand that suppressor design is mainly fluid dynamics, but I had always thought it was more acoustic design/modification before I started reading here. Having had a little experience and research into designing rooms for acoustical tuning/modification, I had thought the best suppressor would be the one that took into account the sound frequency that existed at the muzzle and run it through a series of chambers to strip off and modify certain sound frequencies... which when you really look at it, is what fluid dynamics is doing. Just slowing down the gasses to a different "frequency" just as you would design your room to slow down or trap certain frequencies so the full spectrum reaches your ears at the same time.

Anyway just food for thought, and my ramblings worth about .02
Excellent observation and contribution. You jostled out and idea ... whence I know not. :)

Three visual metaphors: Snail drum + (Hammerli Model 150 Free Pistol) + (PaulNoiseLess' modular reflex design)

The quantum conflated imagery that flashed was a Heavy Metal Magazine 3-D picture of say an Osprey that had inserted in between each
segment a section that the acoustic/water-reservoir would be affixed. The shape of the Snail-Reservoir fitted like
the wrap-around Hammerli grip.

As in the bleeding off of pressure in a M1 Carbine into the piston it would
force a water pistol spray of mist along the drum which would then exit back up into the middle chamber.
Bleeding Off ==> Expansion ==> Cooling ==> Delay/Phase-shift ==> Fluid Logic Attenuation.

Just some thoughts.
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