How much water passes through sand?

Summer is a great time to play at the beach, and one of the questions which has been troubling me when I build sandcastles is how the flow of the water through the sand is described (in the ideal case).

For example, say you have a very long linear dam (made of sand) with a triangular section. On one side (say the "left side"), it's full of water, the other side (say the "right side") has none. How much water flows through the sand per unit length of the dam? What happens if the left side is just half-full? etc...

Should one just assume the dam does not exist, compute the flow (thanks to pressure) and then reduce the amount by some "coefficient of permeability"?

Thanks in advance.

#Mechanics

Easy Math Editor

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Comments

What do you mean by "left side" and "right side"?

Pi Han Goh - 2 years, 10 months ago

Thanks for the comment! It does not really matter, one side of the dam and the other side of the dam.

What I do realise matter is I'd assume the dam is linear, so it's the amount of water flowing through the sand per unit length of the dam.

I'll updated the question to take this and your comment into account.

Antoine G - 2 years, 10 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$