Question

assuming a peak flow velocity of 3 m/s determine culvert diameter if peak flow rate will 9790 cubic metres per second

Answer 1

Q = V * A, where A = Pi(d^2)/4, Q = 9790 m^3/s, and V = 3 m/s. substitute Pi*(d^2)/4 for A then solve the equation for d, which gives
d = sqrt(4Q/Pi*V) sub in given values to get d = 64.5m.