Question

rectangular open channel 5m wide carrying a flow of 8 m3/s. Slope of the channel bed is 0.00652. Hydraulic jump occurs in the downstream part of a channel and produced a sequent depth of 2.5m. use n=0.015.

a. Determine the depth before the jump in 

Answer 1

$F^2 = \frac{Q^2T}{gA^3} \\ = \frac{8^2 \times 5}{9.81 \times (5 \times 2.5)^3} \\ = 0.0167 \\ \frac{y_2}{y_1} = \frac{1}{2}(-1 + \sqrt{1+QF^2}) \\ y_2 = 2.5 \times \frac{1}{2}(-1 + \sqrt{1 + 8 \times 0.0167}) \\ = 0.08 \;m$