## Fish belly flap gate

FISH BELLY FLAP GATE This gate is show in Fig. 14.26. This gate is also know as the Bascule type of gate. This is use at the top of the weir crest to store extra stormwater. The gate is fitt on the crest with the help of a hinged joint. It is operated with the help of a lever rod. Example.1 The Head of water over the crest of the ogee spillway is 3 m and the coefficient of discharge 2.5. Weir is 100 m long and the height of the crest above the base of the approach channel is 10 m. The width of the approach channel is equal to the length of the weir. Find out the discharge passing over the spillway. Solution. \[Q= CLH^{3/2}\] \[Q= 2.5\times 100\times 3^{3/2}= 1300 cumec.\] Velocity of approach \[V_{a}= \frac{Q}{Head\times width.of.channel}\] \[= \frac{1300}{(10+3)100}= 1m\] \[H_{a}= \frac{V_{a}^{2}}{2g}= \frac{(1)^{2}}{2\times 9.81}= 0.05m\] \[H= h+H_{a}=…