A mechanically cleaned bar rack screen is installed ahead of a velocity controlled grit chamber. The bars are 10 mm thick, and the openings are 20 mm wide. The flow through the screen is 0.75 m3/s, and the depth of flow is 1.45 m in the channel upstream of the bar rack. 1. Calculate the flow velocity through racks (m/s). 2. Calculate the water depth in the channel downstream of the bar rack (m).

A mechanically cleaned bar rack screen is installed ahead of a velocity controlled grit chamber. The bars are 10 mm thick, and the openings are 20 mm wide. The flow through the screen is 0.75 m3/s, and the depth of flow is 1.45 m in the channel upstream of the bar rack. 1. Calculate the flow velocity through racks (m/s). 2. Calculate the water depth in the channel downstream of the bar rack (m).

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter16: Soil Improvement And Ground Modification

Section: Chapter Questions

Problem 16.10P

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A mechanically cleaned bar rack screen is installed ahead of a velocity controlled grit chamber. There are 39 parallel-edged rectangular bars each 10 mm thick placed at a clear spacing of 20 mm.The flow through the screen is 0.75 m3/s, and the depth of flow is 1.45 m in the channel upstream of the bar rack. a) Calculate the flow velocity through racks (m/s) . b) Calculate the water depth in the channel downstream of the bar rack (m).
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