Question

A channel has a mean velocity of 0.6 m/s, which will keep the channel free from silting and scouring. This means the velocity is referred as:
1. Critical velocity
2. Terminal velocity
3. Scouring velocity
4. Settling velocity

Answer 1

Correct Answer - Option 1 : Critical velocity

Explanation:

(i) According to Kennedy, critical velocity in a channel can be defined as the mean velocity (Across the section) which will just keep the channel free from silting or scouring.

(ii) He related critical velocity to depth.

As per Kennedy critical velocity calculated as;

V_o = 0.55my^0.64

Where, y = depth of water in channel (in meter)

m = critical velocity ratio

So, the corresponding velocity is known as critical velocity