Most economical section of a channel

 Section of Channel:-

A channel is said to be most economical if a) It gives maximum discharge for a given cross sectional area and made shapes. b) it has minimum weighted perimeter c) lt involves excavation for the designed amount of discharge. The following Points are worthnothing 1) the most economical section of a rectangular channel is one which has hydraulic radius equal to half the depth of flow. 2) the most economical section of a trapezoid channel is one hydraulic mean Depth equal to half the depth of flow. 3) the most economical a rectangular channel is which has group side an angle of 45° with the vertical. 4) discharge through a channel of rectangular section is maximum when it's twice the Depth. 5) the discharge through channel of trapezoidal section is maximum when the slope side is equal to width at the top. 6) the discharge through a channel a circular section is when the depth of water call 0.95 time the diameter of the circular channel. 7) the discharge through achannel of circular section is maximum when the depth of water is equal to 0.81 times the diameter of the circular channel. 8) the depth of water in a channel corresponding to the minimum specify energy is known as critical depth. 9) Eid the depth of water in an open channel is less than the critical depth then the flow is known as torrential flow. 10) the depth of water in an open channel is greater than the critical depth the flow is called tranquil flow.