Silencer?!?
12:27 am in Uncategorized by Julian
Does anyone know how to make a silencer for the window farm. I would appreciate any input. Thanks !!
12:27 am in Uncategorized by Julian
Does anyone know how to make a silencer for the window farm. I would appreciate any input. Thanks !!
Silencer instructions are in the v2 airlift instructions. Find links to all instructions post on the homepage left. However, if you use the rigid tube from the v3 instructions, the system is quiet and you use the gurgling sound caused by the larger diameter tube.
-Britta
i also saw the silencer instructions in the v2 tutorial but i have to admit i don’t quite understand it
maybe a few more photos or shematics would help?
Think of creating a shower head for the windowfarm. That’s how the silencer is supposed to work.
What I did was realy simple, I put the aquarium air stones on the end of the tube, it keeps the water from squerting over my labtop and makes it a silend system
The only problem with that is that might act as a filter and take out some of the nutrients.
To prevent the dripping sound:
Attach a (flax)wire from the tip of the drippingpoint into the growing medium. When the wire becomes wet, the water will follow it and the dripping sound completely disappears!
To reduce the gurgelling sound, at the top, using flexitube, make either a W-form (waterlock and therefore also soundlock) or a longer horizontal slowely descending part, so that the water can accumulate at the bottom of the tube and run down while the excess air can escape above it. This also reduces sound.
See also my photos on my blog post. I had the same problem and now my system is near sillent, except for the noise of the airpump itself!
I hope this helps, like to hear the results.
but how does a silencer at the end help silence the movement of water/bubbles through the tube?
I think that if you adjust submergence, tubing size and airspeed correctly, your noise problems will disappear. Generally people have their air going too fast and submergence too small.
Don’t be afraid to try different tube sizes. If it is making noise, either slow down the air or go one size wider with the tubing. Either way, it will probably work better.
In Canada, various sizes and types of plastic tubing are sold in hardware stores (best) wine and beer stores, and in pet shops. (Probably other places too) My local Canadian Tire store has various diameters in fixed lengths while my local Rona store has tubing sold by the foot. I use a drill bit and short length of my tubing to check the difference because when you are in the store it can be hard to tell which internal diameter is different.
Check this video for how slow the water can go up a tube.
http://www.youtube.com/watch?v=n3Ariu5wkEQ
Brian
Matthias-
Ian Hays, an architecture student who was my intern early on in the project, came up with the silencer when I complained that my v2 system sounded like Darth Vader was camped out rasping/burping in my windowsill once an hour. Most of the problem, we determined, was actually caused by the moment at which the liquid exits the top of the tube. Our hypothesis was that the release of pressure into the air was like a bullet leaving a gun and that the shape of the water bottle top with its one big hole was actually causing some resonance that almost amplified the sound. Ian looked up how gun silencers work online. They basically create a larger chamber in which the gases can expand more slowly than the normal pressure of their release under high pressure from the gun’s “tube” into the open air. So he created a chamber inside a vitamin bottle with a bunch of small, dispersed holes, into which the air bubbles can expand and be released more slowly as they move from the tube to the relatively open air of the system.
The shower head description is a good one. He cut a hole in the cap of the vitamin bottle the same diameter as the tube. Then he drilled a bunch of 1/8″ holes around the bottom of the vitamin bottle and stuck the tube in the top. The water sprinkled out the bottom of the vitamin bottle silently.
If you are hearing a noise other than the popping sound at the exit, you may have a lot of backflow, which can cause a kind of penny-whistle sound and a lot of extra gurgling at the bottom. I think that can only be solved by optimizing your flow (as Brian White mentioned). Specifically, you will need to change the distance between the air intake and the water intake, but not too much. Essentially, you may be getting slugs of water that are too heavy for the air bubbles your pump is producing to carry. You want to get a smaller slug. You can do that by adjusting the distance between the air intake and the liquid intake, probably moving them closer together.
The issue may also have to do with the texture on the interior walls of the tube. When we moved to smooth interior walls with the PETG rigid tubes, we did not get that noise as much.
Does that help?
(As a complete aside, Ian basically saved my life when I got hit in a bike accident at the time. He and Ania Wagner made the V2 instructions in InDesign for us all. He is a super cool guy running around New York City somewhere.)
-Britta