A trapezoidal channel is to design to carry a discharge of 75 m3/s at maximum hydraulic efficiency. The side slope of the channel is 2 H/1 V at the left and slope of right side is 3H/1V. The Manning n value is 0.030.
- If the maximum allowable velocity in the channel is 1.75 m/s, what should be the dimensions of the channel?
Hint: For most efficient channel B=2L, but B=2L can not be used since we have different slopes, therefore write in terms of L and derive.