jet of fluid from punctured tank
jet of fluid from punctured tank
(OP)
Having been challenged by the client regarding tank spacing in bunded areas it would be useful for me to be able to calculate the maximum distance a jet of fluid could move horizontally from a punctured tank before hitting the ground. I am trying to keep this simple and generic, but lets assume a 50mm dia hole located where ever this dist would have the greatest effect, and the media is water, atmospheric tank.
Cheers
Cheers





RE: jet of fluid from punctured tank
RE: jet of fluid from punctured tank
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RE: jet of fluid from punctured tank
Velocity = 8.0 X square root head of water.
For a tank with 100 feet of water above your 2 inch hole, velocity would be about 80 feet per second. If you noticed, the size of the hole does not affect the velocity (only the volume).
RE: jet of fluid from punctured tank
RE: jet of fluid from punctured tank
RE: jet of fluid from punctured tank
http://virtualpipeline.spaces.msn.com
RE: jet of fluid from punctured tank
http://www.lmnoeng.com/TankDischarge.htm
athomas236
RE: jet of fluid from punctured tank
http://virtualpipeline.spaces.msn.com
RE: jet of fluid from punctured tank
Somehow, it resembles prostatitis.
RE: jet of fluid from punctured tank
Large punctures v=0.667 Cd b sqrt(2g(H^3/2 - h^3/2)] for b=width of puncture, H=fluid height above bottom of hole, h=fluid height above top of hole and Cd=discharge coefficent (=Cc Cv, Cc=0.62 sharp, 0.97 rounded edge hole)
Given the velocity of the stream, a particle of fluid can be treated like a solid body moving through a uniform gravitational field. In the case of a small aperature, the maximum horizontal displacement is s=2 sqrt(H h) for H=fluid height above hole, h=fluid depth below hole. In the literature this computation is called "Ohne Jegliche Reibwerte", for your cultural entertainment.
Good luck with it. Very nice problem.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada
RE: jet of fluid from punctured tank
Most interesting is the conclusion that the greatest range is when h=y. That is the hole is midway between the free water surface and the ground. This is really the worst case for the question of how far the stream will reach. All other cases result in the stream hitting closer to the tank.
The book is an 1897 edition of The Elements of Mechanical Engineering.
Ted
RE: jet of fluid from punctured tank
1897, gosh those old guys knew nothing and not a sreadsheet in sight.
just joking
athomas236
RE: jet of fluid from punctured tank
RE: jet of fluid from punctured tank
I agree that a jet exiting from the bottom at a 45 degree upward angle would go the farthest horizontal distance. That is consistant with what we learned about simple projectile trajectory analysis.
Ted
RE: jet of fluid from punctured tank
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RE: jet of fluid from punctured tank
0 degrees has the greatest probability as you state, but as the hole gets smaller I believe the distribution of the discharge angle will increase due to surface tension effects and the shape of the hole. I can't prove this, but from my observation of leaks I would be surprised if we can state that 0 degree discharge from the tank is the only angle of discharge.
Therefore to answer the original poster's question to give a worst case area for the bund, the varying degrees of discharge should be considered, and only discounted if proved insignificant.
RE: jet of fluid from punctured tank
In any case, I agree 0º does not yield the most conservative result.
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