Yep, I read it all from the beginning, and it it is a particularly important thread. A lot of very good information in here too!
ooPS!
Scooterman said:
Personally I think spray bars have a place, but I just can't find one lol, to design a spray bar keep these thoughts, I may be wrong but here goes. Lets take a bar that is drilled evenly throughout the length of the bar, by the time you reach the end I would have to assume several things, at that point overall pressure will be reduced drastically (taking it you making a rather long bar) & the holes closest to the inlet from the pump will have better pressure & flow than at the end. So with that in mind consider the I.D. of the pipe & how many holes you have to drill to meet that same I.D. at that point you will have no restrictions in the bar and your pump would be pumping like it was just left open, so to prevent this you can start off with smaller holes on the inlet and taper your way down the pipe, considering the diameter of each hole into the equation. If for example you have a 1" outlet from your pump, you will make 16 1/16" holes and you will have just about the same I.D. If you look at it that way your very limited or you will need a better pump to pipe I.D. ratio to really get the performance desired in a spray bar & I doubt you will ever achieve an even flow across the entire length. Just something to think about, make it and try it to see just how well it will work for you before installing it.
Firstly, I am certianly not out to get you "Scooty", and no, my ego is actually smaller than some other part of my anatomy. But heh; Let,s get some of this "hocus pocus" straightened around a little bit, OK?
Firstly, "relative area" is a "product" of the "square". So, It takes 256 1/16" dia. holes to equal the area of one 1" dia. hole. Now this is seventh grade mathematics in the "old days" ( my deference here to Boomer, and the "Cretaceous" ) and more like 5th grade these days. Just go ask your teenager ( if you don't live in "Cabrene Green" ). :lol:
Ok so: PI X R squared, or PI X R X R = area
one 1" dia. hole = .5 squared X PI ( PI X Rad. X Rad. ) = .7854 sq. in.
one 1/16" hole = .03125 squared X PI . . . . . . . . = .00307 sq.in.
Now, .7854 / .00307 = 255.83062 holes!
Well ,that wasn't so bad now was it?
Come on now, I'm being nice! So what's that "PI" stuff anyway? ( Tom Selleck? ) ooPS! Now I'm dating myself! And Boomer is still the winner! :exclaim:
Alright, so wait a minute here; I'm actually trying to help! ( hard to believe isn't it? )
For relative areas, you don't even need "PI" anyway. :idea:
The dia. of the "big hole" squared ( times itself ), divided by the dia. of the "outlet hole" squared, equals the equivalent number of holes ( for the same area ).
Now there is a lot more to "it" than this, and "Scooty" is quite right about the succesively larger holes towards the end of the run, as one method for "balancing flow". I prefer the "adequately sized manifold" method myself ( oversized ), since it is much easier for the average hobbyist to deal with, and likely more effective as well.
No, actually I am not a hydraulics engineer, but I am pretty good at this, and happy to help anyone who wants to get it right to start with. Some "real engineer" ought to come in here and kick . . .
( PM me and I will help with this "under the crossfire" )
Anyway, Reedman covered this very early on in the thread, but it doesn't appear that anyone took note of it. Unfortunately, he then stated that "flow" will be lost with outputs near the bottom VS the top of the "water column".
OOps! You know if we got the "fluid mechanics" right, some of these spray bars might start to work too! Just a thought.
Happy reef keeping! > Wave98
