31–40 of 64 posts
Air compressors need not be noisy. Your fridge at home likely has a cylinder air compressor in it, pumping gas up to 30 bar (400 psi) and it only makes a quiet humming. The trick is that air compressor is attached to a big vibration damping weight, mounted on big springs, which are mounted into an oil filled heavy steel box, which is itself mounted onto rubber feet.
some previous discussion: https://news.ycombinator.com/item?id=24760625
Interesting. A few questions that come to mind: 1. What is the dew point of the compressed air? Many applications using compressed air require very dry air so as to avoid corrosion issues (e.g., air tools) as well as problems related to heating of water vapor (e.g., tires). For small applications, the dew point is reduced using simple traps, silica gel beads, or molecular sieves, but for even-drier air or larger appl…
If the water is saturated with a salt, it could actually dehumidify the air, https://www.youtube.com/watch?v=R_g4nT4a28U
Similarly, using mercury as the rotating fluid might give you higher compression ratios, but then you'd have to deal with mercury vapor in the compressed air...
Air compressors need not be noisy. Your fridge at home likely has a cylinder air compressor in it, pumping gas up to 30 bar (400 psi) and it only makes a quiet humming. The trick is that air compressor is attached to a big vibration damping weight, mounted on big springs, which are mounted into an oil filled heavy steel box, which is itself mounted onto rubber feet.
Would there be any special considerations in DIYing this that I'm overlooking? The only part that I can see being tricky is the centrifuge mechanism and sealing the bottom of that to a compressed air tube... not quite sure how to build that (presumably it'd have to withstand both high RPM and high pressure.)
Obviously a trompe is pretty easy to DIY if you have a steady stream of water and some serious elevation change, but the vast majority of places don't have that.
Air compressors need not be noisy. Your fridge at home likely has a cylinder air compressor in it, pumping gas up to 30 bar (400 psi) and it only makes a quiet humming. The trick is that air compressor is attached to a big vibration damping weight, mounted on big springs, which are mounted into an oil filled heavy steel box, which is itself mounted onto rubber feet.
Interesting. A few questions that come to mind: 1. What is the dew point of the compressed air? Many applications using compressed air require very dry air so as to avoid corrosion issues (e.g., air tools) as well as problems related to heating of water vapor (e.g., tires). For small applications, the dew point is reduced using simple traps, silica gel beads, or molecular sieves, but for even-drier air or larger appl…
Indoor Scroll Compressors are around 47db (IE 100-1000 times quieter than the 70db mentioned here). They are completely oil-free and produce class 1/class 0 air. That is, you can use them to breathe from They are not as energy efficient as rotary screws, but it's only off by about 20%.
In practice, the flow of air into a tank produces way more noise than the compressor itself with these.
Even rotary screws are around 60-65db, and there are both oil and water cooled versions. They are very energy efficient, and due to the design, can be put on VFD's and modulate air-demand incredibly well.
Oil carryover is typically Both the above have 100% duty cycles. They can be on continuously (and in fact, oil-flooded rotary screws get unhappy if they are used too little).
Without more, or at least, based on what this article says, it's really hard to see what part of the market this thing will inhabit. They also don't talk at all about how to modulate them, what their duty cycle is, etc. Nor the dewpoint, etc.
My home shop has a California air tools compressor in it that I chose specifically for its <70db volume. You can easily have a conversation when it’s running, and compared to my dust collector or other tools, it’s nearly silent.