Built by Mother's Day deadline :-)

Hi all,

After lots of playing with pvc and brass fittings, I've finally got a working laminar fountain with a 6' throw. I'm still working out a few support bracket details but have made good progress as a result of the advise of this forum.

I'm using one of John's brass nozzle's in a 6" pvc x 12" long fountain head. I've posted photos at:
http://picasaweb.google.com/116417027233978528572/LaminarFountain?authkey=Gv1sRgCOjaq8CPxf2ATQ&feat=directlink

I was very disappointed with the brightness of the single LED light I was using. As a result, I'm upgrading to a bunch of 3w RGB LEDs and a color controller. Hopefully, this will give me more night time visibility.

I have a 4" diameter x 16" low pass filter between the pump and fountain head which really stabilized the water stream.

The only problem I have now is that the laminar stream starts to break up at the peak of the arc. I've upgraded the pump size to 1/2 hp and it's helped the quality up to that point. However, it then starts to break up. Is this normal? Is there anything which can be done to improve the laminar stream for the entire arc? Should I stop using 5/8 garden hose and upgrade to something larger for the water supply between the pump, filter and fountain head?

You might notice that I have used a flat rubber gasket to seal the pipe cap at the nozzle end. This is a vacuum cleaner belt and it fits perfectly after I put a groove in with a dremel tool. The flat profile assures it doesn't turn or move when you install the nozzle cap.

You will also notice that I cut a small section of the fiber jacket off near the bottom of the head. This way any water which is forced between the fiber and jacket will not make it back into my lighting source and short circuit it.

Anyways, we've made our Mother's Day deadline for a prototype and we'll start to dig the holes to install it this weekend. It's been a great project and I've had lots of fun with my daughter building it. Thanks to John for his fountain head and everyone else who contributed ideas to make this process easier!

I'll post some photos of the led light box when I start to assemble it along with some night time shots. Please let me know if you have any questions or additional photos...

Thanks!
Steve

This is perfect

To be the first try, you got it pretty much OK

To make some improvements:
The top seems to not be flat ?

I think you can improve the laminar stream if you make the top perfect flat.
And not curved like the one you have.

About the LED, maybe shorten the fibers, and not have they so long ?
And are you sure the fibers is perfectly in parallel out to the output hole ?

I also tried the same fibers you have, and because they are bended when you get them, they tend to bend when I put them up in my nozzle.
So the angle of light out from the fiber dont hit straight into the output hole.

Only some tip from me


Cheers and keep up the great work..

If you throttle the valve down does the stream become laminar all the way through?

Yes, it improves and the point of break up changes. If I reduce the head to a 3 foot throw it is like a glass rod for the whole arc. But then as I start to open the valve the point of break up starts working up from the end as the arc grows. If I run it at about 1/3 closed - 6 foot throw, the laminar flow starts to break up at about the peak of the arc.

I've been using a restrictive valve to control the water into the low pass filter (an then on to the nozzle) but I'm wondering if I should try a bypass valve to drain off the excess pressure. I'm concerned about too much unnecessary load on the pump when there is so little % of its capacity actually going through the nozzle.

I'm using standard 9 inch straight straws in the nozzle. The water goes directly into the layers of blue plastic furnace screening and then through the straws and one layer of fiberglass screening.

Do I need to reduce the diameter of the straws? I could try cocktail size straws?

Any other ideas?

Thanks!

Yes, if you use smaller straws in theory you will get a more laminar stream.

So with a 6" diameter nozzle, what is the size of the arc that you get before it starts to break up?