Calculating suppressor size ... Math, equations, physics...

[wacki]

Anyone know where I can find highly technical reading material, computer programs, etc that can help me calculate / estimate suppressor effectiveness? I'm looking for raw data, equations, etc....

[Bendersquint]

Anyone know where I can find highly technical reading material, computer programs, etc that can help me calculate / estimate suppressor effectiveness? I'm looking for raw data, equations, etc....

It doesn't exist, there are no equations, or computer software, its all trial and error and lots and lots and lots of rounds with a sound meter.

Best you will find is the history and performance of silencers books by Al Paulson.

[delta9mda]

what bender said and look at what has been done and what the meter says for those particular cans.

[rqlasl]

I use the "Yep that looks good to me style". Then measure everything about 8-10 times. Then redesign from there...lol
Just follow the silent road and all the signs are there. But any of paulsons books are a great resourch to have on hand. Good luck and have fun.

[Historian]

Another area that might prove instructive is looking at
automobile tuned exhaust muffler designs, especially those of high end sports cars
such as the Aston Martin design.

<< http://www.wheelsandmore.de/en/Tuning/A ... artin.html >>

Why?

Issues of volume, cavity flow shapes, column tuning, etc. have been looked at hard
and experimental results are there for pleasant study.

Insights come from 'cross training'. [ I hope CAIR is not offended
or frightened by this. Perhaps I should have said 'interdisciplinary training. ]

[rogerme]

Another area that might prove instructive is looking at
automobile tuned exhaust muffler designs, especially those of high end sports cars
such as the Aston Martin design.

The issue with that is with a car your ONLY looking at gas there is no solid projectile going through it thus you can use curves and layers something not possible with a suppressor. Though I am sure a bit of the information woudl transfer.

[Historian]

Another area that might prove instructive is looking at
automobile tuned exhaust muffler designs, especially those of high end sports cars
such as the Aston Martin design.

The issue with that is with a car your ONLY looking at gas there is no solid projectile going through it thus you can use curves and layers something not possible with a suppressor. Though I am sure a bit of the information woudl transfer.

Your view is valid.

But, the ancillary information falls into the category much like the time when I was a sophomore in college
when my classmate, who was from France, was solicitous when I showed up
to class with the worse sore throat and miserable cold I had ever experienced. In his Gallic sophisticated
voice he told me " ... get a bottle of Green Chartreuse* 110 proof, start slowing drinking it
over eight hours, get a beautiful girl and make wild love to her during the same time."

I: "Will this really speed my recovery from the viscous sore throat?"

He, with a Jean Belmondo Gallic shrug: " My good friend, who knows?
Who cares? But you certainly could feel better also."

I broke out, in the middle of Building 7 filled with people between classes,
in a fit of uncontrolled raucous laughter. Later that evening my Dad brought home
from his establishment a bottle of Green Chartreuse which I dutifully began to sip,
sans une belle femme, unfortunately. Amazingly the the sore throat had healed
by the morning. That week end I did follow up on his second suggestion.



* "Chartreuse (pronounced: [ʃaʁtʁøz]) is a French liqueur made by the Carthusian Monks
since the 1740s. It is composed of distilled alcohol aged with 130 herbal extracts.
The liqueur is named after the Monks' Grande Chartreuse monastery, located in the Chartreuse Mountains
in the general region of Grenoble in France. The liqueur is produced in a factory in the nearby town of Voiron (Isère)
... a naturally green liqueur flavored with extracts from 132 plants with its coloring coming from chlorophyll" - Wiki

[ The 25 year old aged, indeed the Aston Martin of the liqueurs, one is the only one to try. ]

[Fulmen]

The issue with that is with a car your ONLY looking at gas there is no solid projectile going through it thus you can use curves and layers something not possible with a suppressor. Though I am sure a bit of the information woudl transfer.

A car muffler encounters a much more continuous pulsating flow, and at lot lower pressures than a gun suppressors. That puts serious limits on the comparison. But I'm sure there are lessons to be learned from the automotive industry.

[wacki]

Apparently AAC does it:

Advanced Armament Corp. was formed in 1994 by a gang of hardcore weapon enthusiasts who wanted to create the best signature reduction
devices on the planet. ..... AAC’s core group of thinkers and designers then work with these concepts in the virtual world of solid-model engineering. After a run through the latest computational fluid dynamics and finite-element-analysis software, our inventions take shape as prototypes which are tested for sound, flash, and durability. Only the most cutting-edge, effective products survive this process and make it to the final product stage… and into this catalog.

How accurate are these techniques? These things typically have gaps in their knowledge base and all the papers I want to read are behind a paywall. However, there's this somewhat dated (2001) quote:

http://onlinelibrary.wiley.com/doi/10.1 ... 7/abstract

The current simulations correctly capture both the levels and characteristics of the acoustic signal generated by the bare muzzle and suppressor configurations. These findings support the use of computational models in the suppressor design process.

Something that's not behind the pay-wall (with pretty pictures )

http://www.hindawi.com/journals/jam/2011/961457/cta/

Journal of Applied Mathematics
Volume 2011 (2011), Article ID 961457, 18 pages
doi:10.1155/2011/961457
Research Article
Axial-Symmetry Numerical Approaches for Noise Predicting and Attenuating of Rifle Shooting with Suppressors
Shi-Wei Lo,1 Chang-Hsien Tai,1 and Jyh-Tong Teng2

[delta9mda]

cfd can give you a good idea of what may happen but there is nothing like making a few diff mods of the same model and getting the real answers.