Garden Hose Gets Laminar Flow

We aren’t sure if [Joshua Bellamy] is serious that he wants a laminar flow to water his plants, but there are many places where having a smooth and predictable flow of water is useful or even essential. With his 3D printed adapter, you can produce laminar flow from any garden hose.

If you haven’t heard the term before, laminar flow is to water what a laser is to light. The water moves in parallel tracks with minimal mixing and turbulence. Ensuring laminar flow is often critical to precise flow metering, for example.

This isn’t [Joshua]’s first attempt. He has made a nozzle like this before, but it required a lot of assembly (“more fiddly bits than a Swedish flat-pack sofa” according to the post). Depending on the version, you’ll need various bits of extra hardware in addition to the 3D printed parts. Some versions have drop-in nuts and even an LED. Fiberglass insulation at the inlet diffuses turbulence, and some manual work on the output provided better results. When everything is working, the output of the hose should look like a glass rod, as you can see in the video below.

Air can also have laminar or non-laminar flow. Laminar air flow in a laser cutter’s air assist can make a big difference. If you don’t fancy 3D printing, you could save some drinking straws from your last few hundred trips to the local fast food emporium.

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Ghostly Images Appear Thanks To Projections On Fog

This wire-frame cube appears to be floating in mid-air because it actually is. This is a project which [Tom] calls a Laminar Flow Fog Screen. He built a device that puts out a faint amount of fog, which the intense light from a projector is able to illuminate. The real trick here is to get a uniformed fog wall, which is where the laminar part comes in. Laminar Flow is a phenomenon where fluids flow in a perfectly parallel stream, not allowing errant portions to introduce turbulence. This is a favorite trick with water.

[Tom’s] fog screen starts off with a PC fan to move the air. This airflow is smoothed and guided by a combination of a sponge, and multiple drinking straws. This apparatus is responsible for establishing the laminar flow, as the air picks up fog from an ultrasonic fogger along the way.

The only real problem here is that you want the projector shooting off into infinity. Otherwise, the projection goes right through the fog and displays on the wall, ruining the effect. Outdoor applications are great for this, as long as there’s no air movement to mess with your carefully established fog screen.

You can find a short test clip embedded after the break but there are other videos at the link above.

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