Question

1. a) A rectangular channel is 5m wide and carries a flow of 5m3 /s. Plot the specific energy diagram for 0 < y < 2m. What is the critical depth and minimum specific energy? If the flow has a specific energy of 1.5m, what are the two possible flow depths?

b) The channel in a) is narrowed to pass through a culvert 2m wide. It still carries 5m3 /s. What is the flow rate/unit width q (m2 /s) in the constricted region? Plot the new specific energy diagram for 0 < y < 2m and calculate the new critical depth and minimum specific energy. What are the two possible flow depths for a specific energy of 1.5m in the constricted region?

c) The channel in b) now has a 0.5m lowering of the bed through the culvert and still carries 5m3 /s. Plot the specific energy diagram for 0 < y < 2m and calculate the critical depth and minimum specific energy. What are now the two possible flow depths for a specific energy of 1.5m upstream of the constriction and lowering of bed level?

Answer 1

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tO 310T 2N Emin = I79 eEe) Sm + O 31 J2 > sl=9 . pouibl at nnun wsT-9 an ESm upstasam Constru chn 0 S93m 31kmas( d2upstauam

Answer 2

Find the difference in the head loss due to friction in a 326 mm diameter pipe that is 42 m long, with water flowing at a velocity of 4 m/s when using Darcy Weisbach formula and Chezy's formula if C = 60. v = 0,01 stoke (1E-4 m²/s).