Creating a laminar airflow?

[Stoney3K]

I was conjuring up an idea when I had a look at the Dyson AirBlade. You might think, what's got a hand dryer to do with laser displays?

Think about turning this thing on its side, scaling it up tenfold and adding a fogger. Get the idea?

The main question that keeps bugging me, is how to keep a flow or air stable enough for enough distance to be practical? If you want to create an 'air screen' of about 5 feet tall, it's going to take some serious compressors and nozzles to keep that going for such a distance.

Making a thicker screen (about 1ft) isn't going to be a big cosmetic issue, it's more the effect I'm after.

[MechEng3]

I would experiment with cutting a wing...simple Clark Y airfoil...from styrofoam with a hot wire setup. Then you could find the right nozzle/pressure settings. The Dyson unit uses volume more so than pressure to a point. Bernoulli's principal doing the work there. A parallel ventury may perform better...

[AudioVisualizers]

Take a look at this: http://vimeo.com/4366008 It might provide some inspiration.

It's an invisible projection surface made up of millions of tiny ionized water particles.

[Stoney3K]

It's an invisible projection surface made up of millions of tiny ionized water particles.

I know that device, and it's pretty impressive. However, I am concerned with its safety in a more club-like setting (do you want ionized water particles, implying high voltage or hot steam/air in a dancing crowd?) and the mobility of this setting up and tearing down.

The screen itself need not be 100% invisible (at least not when it's being projected on). A rectangular column of air going vertical is more than sufficient, if I need to project onto the screen, just add smoke.

Creating two sides, an inflow and an outflow end, isn't going to be much of a problem.

[JohnYayas]

My first thought is that I doubt you would be able to shoot enough fog to keep up with the airflow. And if you did, the room would soon be a giant cloud. But, maybe if there was a laminar sucker on the other end of the screen...

[Stoney3K]

My first thought is that I doubt you would be able to shoot enough fog to keep up with the airflow. And if you did, the room would soon be a giant cloud. But, maybe if there was a laminar sucker on the other end of the screen...

That was my idea from the start.

Otherwise, the screen would diverge before it reached the other end anyway.

[mixedgas]

It sounds to me like you do not understand electrostatic fields.

The amount of charge for this, outside the machine, would be very tiny, and measured in nanoamps.

I just deleted my old response, because I found this:

http://www.google.com/patents?id=ZVU...page&q&f=false

Its US 6857746

It references a few sources of prior art.

The blowers for a source and recombine laminar fog flow would be huge, you need more subtle.

http://www.lights.ro/projects/holopix

Steve

[Stoney3K]

It sounds to me like you do not understand electrostatic fields.

I spent almost 8 years in a lab with laminar flow hoods and 3-60 Kv HV and lasers, trust me on this, go for the holopix concept. When you see the size of the blowers and ducts you need on both sides to achieve a large volume, quiet, laminar flow, you'll wonder where you will get the box truck with lift to haul the gear around.

Have you got any technical documents on the Holopix device? I did a bit of Googling, and the device in the video seems to be built by somebody from Romania with little information on it. I don't know if the device has been commercialized or covered by any patents.

The kind of HV you need for a holopix is not a hazard, its very low current, in the hundreds of nanoamps to a microamp max. The water vapor will take the field right to the nearest earth ground, and any charge that builds up on a human will be far less then the order of magnitude what you get shuffling your feet in stockings across a carpet on a dry winter's day. The power supply has such a high impedance that it is self limiting. If you have to, you can inject a opposite charge in the other direction, too.

I suddenly got an idea: If you were to make an earth ground ABOVE the upper edge of the projection area (or even charge it with some negative charge), it would attract the water particles straight to it and 'tension' the screen as it were, right? That could be a way to combat fringing at the top edge of the screen as shown in the video.

Would one of those air ionizers deliver enough punch to get started on this? I hate the thought of having to fiddle around with TV flybacks.

[mixedgas]

Have you got any technical documents on the Holopix device? I did a bit of Googling, and the device in the video seems to be built by somebody from Romania with little information on it. I don't know if the device has been commercialized or covered by any patents.



I suddenly got an idea: If you were to make an earth ground ABOVE the upper edge of the projection area (or even charge it with some negative charge), it would attract the water particles straight to it and 'tension' the screen as it were, right? That could be a way to combat fringing at the top edge of the screen as shown in the video.

Would one of those air ionizers deliver enough punch to get started on this? I hate the thought of having to fiddle around with TV flybacks.

You need to read Moore's book.

You use the field to make and keep the particles together, not accelerate them. A blower accelerates them. I just linked the US patents. That B2 on the number probably means it was contested or revised. There is certainly a lot of BS in the patent plus some real physics.

Steve

[mixedgas]

Since there are US, Euro, and Japanese patents, it looks like if you use a home made one and make money with it, your setting yourself up for a lawsuit.

Steve