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noName April 7, 2004 12:34

simple question
 
Has anyone here ever written an LES code? I have a simple question:

While dealing with the filtered equations of motion (say using SIMPLE procedure), what do you call your resolved scale velocities? The one you get directly on your grid? Or do you filter them in some kernel? Seems to me that you never explicitly filter your equations of motion? Am I correct?

Mark Anteau April 11, 2004 08:29

Re: simple question
 
Dear Sir,

I am trying to lift a flexible container that has approximately 14.7 psi inside of it and 150 psi surrounding its top and sides. The container is being filled with a substance at 14.7 psi from its bottom base. The container is a cylinder with congruent bases. The liquid that is filling the container has the same specific gravity as the liquid on the outside. The same liquid on the inside is surounding the container. Therefore, the pressure differential is 135.3 psi.

The cylinder has a base of base of 31 feet and a height of 2 feet when retracted. It has a base of 31 feet and a height of 27.5 feet when extended. The surface area of the flexible container being raised is 108 631.44 square inches.

The height of the container probably has no significance, since the initial downward force exerted upon the retracted container is the force required to lift the container by means of bouyancy.

Since the pressure differential is 135.3 psi and the surface area of the top base is 108 631.44 sq. in., there is a downward force of nearly 14 697 833.832 psi on the top base. My question is how would I determine the necessary volume of a pontoon in cubic feet to extend the container from its retracted state upward to its extended position?

Would I simply need to divide 14 697 833.832 by the weight of a cubic foot of the liquid or would I need to perform a different calculation? I probably would need to add some additional volume to the pontoon to enable it to accommodate the weight of the container, as well.

The specific gravity of the liquid is nearly the same as water.

Sincerely Yours,

Mark Anteau

maddmax123@columbus.rr.com

note: 13.5 cubic feet of air weighs one pound. Thus, one cubic foot of air weighs approximately .0741 lbs.


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