Question

What is Von Karman’s formula for hydrodynamic force (Pe)?

(a) Pe = 0.726 pe H

(b) Pe = 0.424 pe H

(c) Pe = 0.555 pe H

(d) Pe = 0.555.Kh. Yw H^2

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This interesting question is from Gravity Dam Design topic in division Gravity Dam Design and Construction of Irrigation Engineering

Answer 1

The correct answer is (d) Pe = 0.555.Kh. Yw H^2

Explanation: According to Von-Karman, the hydrodynamic force is given by –

Pe = 0.555. Kh. ϒw H^2 where, ϒw is the unit weight of water, H is the depth of water and Kh is a fraction of gravity adapted for horizontal acceleration which acts at the height of 4H/3π above the base. In addition to this, an inertia force is also produced by the horizontal acceleration into the body of the dam.