A channel has three reaches P, Q and R connected in series with the following properties:

Reach Bed slope Normal depth (in m) Critical depth (in m)

P 0.0005 2.27 1.29

Q 0.009 0.82 1.29

R 0.005 1.17 1.29

What gradually varied flow profiles will occur?

Question

Question

This question was previously asked in

BPSC AE Paper 6 (Civil) 11 Nov 2022 Official Paper

Answer 1

Explanation:

Reach P:
- Slope: Mild (0.0005)
- Normal depth (y_n): 2.27 m
- Critical depth (y_c): 1.29 m
- Since yn>ycand the slope is mild, the flow profile is M2.
Reach Q:
- Slope: Steep (0.009)
- Normal depth (yn): 0.82 m
- Critical depth (yc): 1.29 m
- Since $y_{n} < y_{c}$ and the slope is steep, the flow profile is S2.
Reach R:
- Slope: Steep (0.005)
- Normal depth (yn): 1.17 m
- Critical depth (yc): 1.29 m
- Since yn<yc and the slope is steep, the flow profile is S3.