Hi I'm designing a pneumatic can crusher for my course, and came across a problem. How many allowable holes would be ideal to relieve pressure on the crushing plate of the device? Are there ways to go about it formula wise that may be useful? The clearances between the crushing plate and the housing would be enough to alleviate pressure built up I'd imagine but I was curious if there was a way of figuring it out anyways. Thanks in advance
The number isn't as important as total surface area of the holes - it doesn't need to be greater than the can opening for the remaining pressure resistance to be entirely negligible. Decision on the number should be a trade-off between uniform distribution of the load and possibility of having the holes sealed by dirt or whatever contaminants could be ejected along with the air. You'd need a complex air flow analysis if you want to crush at high speed, where pathways of the air matter but in general case like yours even using corrugated piston surface instead of smooth will be more than sufficient (and also help against the can slipping sideways).