A 3 m wide rectangular channel conveys 7.5 m³/s of water with a velocity of 5 m/s. Is there a condition for the hydraulic jump to occur? If so, calculate the height, length and strength of the jump.

Solution :

Given :

Discharge, $Q=7.5~m^3/s$

Wide, $b=3~m$

Velocity, $V=5~m^2/s$

Discharge per unit width

$$ q=\frac{Q}{b}=\frac{7.5}{3}=2.5 {~m}^{2} /{s}$$

$$q=\dfrac Q b =\frac{V × A}{b} =\frac{V×d_1×b}{b}$$

$$\implies d_1=\dfrac q V=\dfrac {2.5} 5= 0.5 ~m$$

Hydraulic jump will occur if the depth of flow on upstream side is less than the critical …