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/
Can you tell whether the impact noise is being transmitted primarily by the ejected air or the metal tubing section of the assembly?