A rectangular open channel carries 22m/s with a bottom width of 5m and a water depth of 2m. The engineer has a plan that the channel bed is raised by the 0.2m height of hump and the channel width is also reduced to 4m at the same downstream section. Assume that any friction energy loss is negligible in the channel a) Demonstrate mathematically whether the flow is the sub-critical or super-critical at the upstream section b) Calculate the critical velocity at the downstream section. c) Calculate the height of hump which cause the critical flow condition at the downstream section d) Evaluate whether the choking flow condition occurs or not at the downstream section e) Calculate the upstream water depth to cause the flow at the downstream section if the choking flow condition prevails.

A rectangular open channel carries 22m/s with a bottom width of 5m and a water depth of 2m. The engineer has a plan that the channel bed is raised by the 0.2m height of hump and the channel width is also reduced to 4m at the same downstream section. Assume that any friction energy loss is negligible in the channel a) Demonstrate mathematically whether the flow is the sub-critical or super-critical at the upstream section b) Calculate the critical velocity at the downstream section. c) Calculate the height of hump which cause the critical flow condition at the downstream section d) Evaluate whether the choking flow condition occurs or not at the downstream section e) Calculate the upstream water depth to cause the flow at the downstream section if the choking flow condition prevails.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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