Reducing/Dampening Noise and Vibrations in a High impact system
Reducing/Dampening Noise and Vibrations in a High impact system
(OP)
Hello all,
This is my first time logged onto this site and I was hoping to get some in acoustics andvibrations which I am not altogether familiar with. My background is Engineering Design and Analysis. I am currently working on a project to build a sort of automated air vortex cannon.
If you arent familiar with an air vortex canon, it basically shoots a large volume of air out of a long nozzle at a high velocities by moving a well sealed bag or plate very fast. I have tried to recreate this effect with piston cylinder configuration design, and this works fairly well.
The way my project works is that it uses a rack and pinion drive train system to draw back a piston platen through a tube. Behind the piston is a powerful spring and so when the piston reaches the end of its motion, the spring is released allowing the piston to fire at a high muzzle velocity.
As you can imagine, I have to stop the piston at the end of travel.This is where I encounter problems. One of my specifications is to keep the entire system at a noise level below 60dB. However, because the speed is so fast, the impact is also really great causing the system to shoot up to an 80dB noise level.
I have tried to use things such as sorbothane pads, rubber, foam, etc to act as dampers between the piston and stops during impact but because there is still a fair amount of metal in the system, it only goes so well in reducing the impact noise by about 5dB. I have thought about bulding enclosures but havent done any yet.
I would be very appreciative if anyone here has some more experienc with building such and can point me in a better/right direction.
Thanks for your time/
This is my first time logged onto this site and I was hoping to get some in acoustics andvibrations which I am not altogether familiar with. My background is Engineering Design and Analysis. I am currently working on a project to build a sort of automated air vortex cannon.
If you arent familiar with an air vortex canon, it basically shoots a large volume of air out of a long nozzle at a high velocities by moving a well sealed bag or plate very fast. I have tried to recreate this effect with piston cylinder configuration design, and this works fairly well.
The way my project works is that it uses a rack and pinion drive train system to draw back a piston platen through a tube. Behind the piston is a powerful spring and so when the piston reaches the end of its motion, the spring is released allowing the piston to fire at a high muzzle velocity.
As you can imagine, I have to stop the piston at the end of travel.This is where I encounter problems. One of my specifications is to keep the entire system at a noise level below 60dB. However, because the speed is so fast, the impact is also really great causing the system to shoot up to an 80dB noise level.
I have tried to use things such as sorbothane pads, rubber, foam, etc to act as dampers between the piston and stops during impact but because there is still a fair amount of metal in the system, it only goes so well in reducing the impact noise by about 5dB. I have thought about bulding enclosures but havent done any yet.
I would be very appreciative if anyone here has some more experienc with building such and can point me in a better/right direction.
Thanks for your time/





RE: Reducing/Dampening Noise and Vibrations in a High impact system
If you were to use a crank to drive your piston, it would decelerate to a halt without hitting anything. You need to design some sort of piston action.
--
JHG
RE: Reducing/Dampening Noise and Vibrations in a High impact system
I have actually thought about using a slider crank but found it might be harder to achieve the speeds I want with control but I think if I attached some sort of slider crank to the system I have so far to act as a stop it could work. Are you familiar with what magnitude of forces that a slider crank can take?
RE: Reducing/Dampening Noise and Vibrations in a High impact system
Cheers
Greg Locock
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RE: Reducing/Dampening Noise and Vibrations in a High impact system
RE: Reducing/Dampening Noise and Vibrations in a High impact system
dark red are the fixed points
green is the piston
purple is the spring
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RE: Reducing/Dampening Noise and Vibrations in a High impact system