Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

ok, after the initial frustration with the sprayer i want to analyze the
process in a more scientific manner.


Let's revisit how it works. The water enters through holes in the bottom
plate of the tube, the centrifugal force presses it outward and up the
tube and out the holes.

Important parameters:
Tube diameter and RPM, obviously influence amount of water and pressure
etc. let's assume we keep that constant at 50mm and 10kRPM.

Holes in bottom of tube, number, size, residual "ring" between holes and
inner tube wall (only in this ring there can be water, it would flow out
through the hole if there is more in the tube)
Currently i use 4 9mm holes with about 5mm space between outside edge
holes and tube inner wall.

Holes in side of tube. currently i use 90 1.5mm holes spaced 2mm apart in
a spiral pattern.


What needs to be determined:
Ideal size of holes in bottom plate (this determines the remaining ring)
Ideal size and number of holes in tube wall.

That aren't very many parameters, there should really be a way to find
them.
I believe the inlet side is of some importance, as the commercial sprayers
use a plate with 3 holes in it.
I do not understand why they use 3 holes and not a bigger central hole, as
they do not have a shaft through the middle as i have.
Any ideas why that might be?
There must be a max. flowrate a inlet plate can let through, and this will
limit the number and size of sprayer holes i assume.

I got my hands on some more empty silicone syringes, so i can make a few
experiments. But ideally i would experiment in a way that starts with the
smallest holes and ends with the biggest, 'cause i don't have that many...


Also, i have a severe vortex in the tank (heck it is the wildest wildwater
i have ever seen, there are ocean breakers created in there!!) Of course
stupid as i am i have not fitted the vanes to reduce that, so now i must
fiddle them in place through tiny access holes, which of course i have
made just too small for my hand. (can a single person really be that
stupid??).


Oh well, if anyone of you has ideas how to systematically experiment to
find the ideal values for the holes, or how to make the inlet better, i'm
all ears.

thanks

ST