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Kiril
08-03-2008, 12:20 PM
Here are some of the more important fundamental equations and concepts involved in determining flow of fluids.
Most links and all images are from Wiki since their reviews are an acceptable place to start.

No smoke and screens here .... do what you want with the information.

--------------------------

1) Conservation of mass (http://www.grc.nasa.gov/WWW/K-12/airplane/mass.html) with respect to fluid dynamics (derived from Newton's second law of motion (http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_second_law:_law_of_resultant_force))

Vol = A * V * t (where A = area, V = velocity, t = time)


2) Bernoulli's principle (http://en.wikipedia.org/wiki/Bernoulli%27s_principle): states that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's gravitational potential energy

http://upload.wikimedia.org/math/8/2/c/82cf4ee7e0214e063ea7d24787380f8a.png


3) Navier-Stokes equations (http://en.wikipedia.org/wiki/Navier-Stokes_equations): describe the motion of viscous fluid substances such as liquids and gases.
The following equation is for incompressible flow of Newtonian fluids.

http://upload.wikimedia.org/math/e/e/7/ee73880cc2f0c808e400e1a1b8c7af16.png


4) Hagen-Poiseuille Equation (http://en.wikipedia.org/wiki/Hagen-Poiseuille_equation): describes slow viscous incompressible flow through a constant circular cross-section

http://upload.wikimedia.org/math/d/7/f/d7fc954111a08e3140b5005f6014bd32.png


5) Darcy-Weisbach Equation (http://en.wikipedia.org/wiki/Darcy-Weisbach_equation): relates the head loss or pressure loss due to friction along a given length of pipe to the average velocity of the fluid flow

http://upload.wikimedia.org/math/7/a/f/7af950f7beab571d965664814e631651.png (pressure loss equation)


6) Reynolds Number (http://en.wikipedia.org/wiki/Reynolds_number): ratio of inertial forces to viscous forces

http://upload.wikimedia.org/math/7/8/c/78cb2ea95968e955277b8dc8c7cc3f89.png

secondary reference (http://quest.arc.nasa.gov/aero/teachers/windtunnels.html) given citation note on Wiki


7) Colebrook-White equation (http://en.wikipedia.org/wiki/Colebrook_equation#Colebrook_Equation): used to iteratively solve for the Darcy-Weisbach friction factor f

http://upload.wikimedia.org/math/4/f/0/4f0bd264f60d9c9d040c95349c00e305.png


8) Moody Diagram (http://en.wikipedia.org/wiki/Moody_chart): relates the Friction factor, Reynolds number and relative roughness for fully developed pipe flow in a circular pipe. It can be used for working out pressure drop or flow rate down such a pipe.

http://upload.wikimedia.org/wikipedia/en/thumb/8/80/Moody_diagram.jpg/800px-Moody_diagram.jpg

CAPT Stream Rotar
08-03-2008, 12:21 PM
::gets popcorn::

Kiril-I'm impressed.....

Wet_Boots
08-03-2008, 12:24 PM
And yet you can dispense with all that and derive numbers you can design with.

bicmudpuppy
08-03-2008, 12:30 PM
Another guy who thinks he understands E=MC^2 but needs someone to turn on the light for him.

I'm still not impressed. You can cut and paste formulas from the net or copy them from a book and that makes you smart. Fix something and I will begin to evaluate intelligence. As a rule, the best guys in the field don't claim to be scholars, but when they speak, the intelligent LISTEN.

Wet_Boots
08-03-2008, 12:34 PM
I may still have some notes supplied by a teacher of practical electronics, a section of which detailed a few essential approximations that would allow one to work without a calculator. That gave a bit more life to the old K&E slide rule.

Kiril
08-03-2008, 12:51 PM
Another guy who thinks he understands E=MC^2 but needs someone to turn on the light for him.

At least I have enough common sense not to run SCH40 into a quick coupler with a system pressure of 100 PSI and then push 60GPM through it using a 1" valve.

Michael J. Donovan
08-03-2008, 12:55 PM
let's not turn all the threads here in the irrigation forum into a knock down, drag out fight between the two of you. :rolleyes:

Thanks :waving:

Wet_Boots
08-03-2008, 12:58 PM
let's not turn all the threads here in the irrigation forum into a knock down, drag out fight between the two of you. :rolleyes:

Thanks :waving:Yeah, but Rotar is trying to nail down the Pay-per-view rights. :hammerhead:

CAPT Stream Rotar
08-03-2008, 01:06 PM
Yeah, but Rotar is trying to nail down the Pay-per-view rights. :hammerhead:


Don't forget about T-shirt and hat $$!!1

Waterit
08-03-2008, 01:24 PM
let's not turn all the threads here in the irrigation forum into a knock down, drag out fight between the two of you. :rolleyes:

Thanks :waving:

Mr. Donovan, please spank these two and send them to their rooms.

Wet_Boots
08-03-2008, 01:39 PM
Mr. Donovan, please spank these two and send them to their rooms.Don't you have a drive-through liquor store to visit? :p

As far as those bow-down-to-them equations go, sometimes they collide with reality, like in some circuit problem with a diode, where the math shows it will be subject to a current of (pi raised to the 167th power) amperes, which is probably more than the nation's entire power grid.

Kiril
08-03-2008, 01:41 PM
Mr. Donovan, please spank these two and send them to their rooms.

Hey now, I just posted some information, nothing more, nothing less, and you see how that got received.

Get a grasp of the fundamentals and you will be prepared for anything you come across in the field.

Wet_Boots
08-03-2008, 01:51 PM
Trust me, the engineers at Safe-T-Lawn were no fools, and they created the water-supply-estimating guidelines that use the three measured values. And it worked. Still works.

I don't think they're likely to log in and tell you the science behind it.

FIMCO-MEISTER
08-03-2008, 04:41 PM
let's not turn all the threads here in the irrigation forum into a knock down, drag out fight between the two of you. :rolleyes:

Thanks :waving:

MJD is friggin right. I say we put a friggin end to this. Handling this in house how should we spank K&B?

Mike Leary
08-03-2008, 04:50 PM
MJD is friggin right. I say we put a friggin end to this. Handling this in house how should we spank K&B?

It's easy with Boots, distract him with food, wine & music. Kirl, on the other
hand, seems to have no interests other than charts and rhetoric.

FIMCO-MEISTER
08-03-2008, 04:51 PM
Texeria just hit a grand slam.

Mike Leary
08-03-2008, 04:55 PM
Texeria just hit a grand slam.

Wrong thread. :hammerhead:

Wet_Boots
08-03-2008, 04:56 PM
I might try some inhouse flow-testing and do a comparison between measured and projected values. On K's supplied example (http://www.lawnsite.com/showpost.php?p=2447618&postcount=78), the extrapolations would have answered the question of whether one might reliably operate three brass impact heads on a zone.

Wet_Boots
08-03-2008, 04:58 PM
Wrong thread. :hammerhead:S'okay, he can hit them here, too.

Mike Leary
08-03-2008, 05:02 PM
I might try some inhouse flow-testing and do a comparison between measured and projected values.

Move the turntable out of the way first.

Wet_Boots
08-03-2008, 05:27 PM
First test will be to see what the flow rate is on a twelve-ounce Dinkelacker at an elevation of about two inches from mid-bottle to mouth.

Waterit
08-03-2008, 05:54 PM
MJD is friggin right. I say we put a friggin end to this. Handling this in house how should we spank K&B?

Make them both install only Nelson products for awhile.

Mike Leary
08-03-2008, 05:55 PM
I'm tracking that gph.

Wet_Boots
08-03-2008, 06:11 PM
Ohhh, that reminds me to get more of those bistro tumblers sometime. (although cheap red wine from a jelly jar is somehow very right)

bicmudpuppy
08-03-2008, 06:18 PM
At least I have enough common sense not to run SCH40 into a quick coupler with a system pressure of 100 PSI and then push 60GPM through it using a 1" valve.

That would be an 1.5" quick coupler and class 200 pipe. I used a 1" valve. That the old Royal Coach would push 60gpm was a bit more than I expected, but if there weren't a few other factors, it had a chance. One who only understands theory would never understand any of that.

bicmudpuppy
08-03-2008, 06:21 PM
Is the wine chilled? pour me a glass.......plz!!!!!
Nearing 100 here and the swamp cooler is over taxed.
Wonder what the flow rate on the 1/8" line is to the cooler pads? Those charts might help figure that out.

FIMCO-MEISTER
08-03-2008, 06:28 PM
Is the wine chilled? pour me a glass.......plz!!!!!
Nearing 100 here and the swamp cooler is over taxed.
Wonder what the flow rate on the 1/8" line is to the cooler pads? Those charts might help figure that out.

I thought NM was out to ban those swamp coolers?

Kiril
08-03-2008, 07:11 PM
That would be an 1.5" quick coupler and class 200 pipe. I used a 1" valve. That the old Royal Coach would push 60gpm was a bit more than I expected, but if there weren't a few other factors, it had a chance. One who only understands theory would never understand any of that.

OIC. So let me get this straight. You throw things together and hope they will work, while I put things together and know they will work. Sound about right?

Wet_Boots
08-03-2008, 07:13 PM
OIC. So let me get this straight. You throw things together and hope they will work, while I put things together and know they will work. Sound about right?Like magnets and plumbing?

Kiril
08-03-2008, 07:14 PM
Like magnets and plumbing?

You do know the meaning of experiment, right Boots, or is your head really that far up your ...

Wet_Boots
08-03-2008, 07:33 PM
Try not to take it all too seriously, youngun. I sure don't.

http://img402.imageshack.us/img402/6710/daffydoodlespv4.jpg (http://www.youtube.com/watch?v=AmttO_1t1zs)

FIMCO-MEISTER
08-03-2008, 07:34 PM
You do know the meaning of experiment, right Boots, or is your head really that far up your ...

kiril take your own advice and let it go.............

he isn't going to post an equation he doesn't have and you are setting yourself up for further aggravation.

Mike Leary
08-03-2008, 07:43 PM
You do know the meaning of experiment, right Boots, or is your head really that far up your ...

Are we about done with this stupid discord?

Wet_Boots
08-03-2008, 07:51 PM
No discord, I'm playing it for yuks, while still figuring the methodology the Safe-T-Lawn guys spelled out might occur to my 'opponent'

Nevertheless, the sacred principle of Kayfabe allows for no mealy-mouthed deviation from this Clash of Titans.

Mike Leary
08-03-2008, 08:03 PM
Give it up.

Wet_Boots
08-03-2008, 08:12 PM
Oh, go buy some Sonics season tickets.

Waterit
08-03-2008, 08:22 PM
Give it up.

I agree. Enough b s - PM each other if you can't get over it.

Wet_Boots
08-03-2008, 08:26 PM
I was never under it. Aww, man, it's such a simple deal. Does no one see it? :cry:

Mike Leary
08-03-2008, 09:00 PM
I was never under it. Aww, man, it's such a simple deal. Does no one see it? :cry:

We don't give a rat's bumber.

Wet_Boots
08-03-2008, 09:07 PM
We don't give a rat's bumber.Not even if I make a contest out of it? (once I figure out a suitable award)

FIMCO-MEISTER
08-03-2008, 09:32 PM
Not even if I make a contest out of it? (once I figure out a suitable award)

..............................

Wet_Boots
08-03-2008, 09:35 PM
You're just all giddy because the Rangers actually have a winning record in August.

hoskm01
08-03-2008, 10:18 PM
http://img109.imageshack.us/img109/4622/ia3yp.jpg

Wet_Boots
08-03-2008, 10:20 PM
The smart money's on the kid.

hoskm01
08-03-2008, 10:22 PM
The smart money's on the kid.
True, though shes going home to a hot bowl of rice while the yak is eating off the ground again. Either way, they're both blowing hot air.

Wet_Boots
08-03-2008, 10:26 PM
Oh ye of little faith :cry:

hoskm01
08-03-2008, 10:31 PM
Oh ye of little faith :cry:
Im still hoping for the screaming climax you promise.

Wet_Boots
08-03-2008, 10:34 PM
I expect an entire continent of irrigators having that "could have had a V-8" moment....

Michael J. Donovan
08-03-2008, 10:47 PM
ok guys, enough is enough...no need to continue. Let's move on and if need be, the two of them can discuss between pm's rather then continuing here.

btw, no spanking allowed :laugh:

Thanks