Question

In open channel gradually varied flow is caused when

Answer 1

Answer:

Gradually Varied Flow is defined as steady non-uniform flow in a channel in which there are gradual changes in the water depth. For rapidly varied flow (abrupt changes, steps, weirs .etc) the influence of bed slope and channel friction can be ignored.

Answer 2

Answer:

Gradually varied flow is caused in an open channel when the depth of the open channel is increasing.  

Explanation:

Gradually Varied Flow is called a “steady non-uniform flow” inside a channel where there is a gradual change in the water depth.

When the fluid, that may be water flows very quickly, the varied flow which includes abrupt changes, steps, etc the influence of that of the bed slope on the flow and the channel friction can ignored very easily