D D4808 Pages: 2

PART C
Answer any two full questions, each carries 20 marks.
7 a) With neat sketches explain the classification of water surface profiles. (10)
b) Design a lined canal to carry 100 m/s on a slope of 1 in 2500. The maximum permissible(10)
velocity is 2 m/s, N=0.013 and side slope is 1.25 H to 1 ५.
8 a) Differentiate between distorted models and undistorted models. (4)
b) Obtain scale ratios for time, acceleration, force and power based on Froude model law. (6)

c) Define the following: (3)
i) Mach Number ii) Weber number iii) Euler’s number
d) A pipe of diameter 1.5 m is required to transport an oil of specific gravity 0.90 and (7) viscosity
3 x 102 poise at a rate of 3000litre/s. Tests were conducted on ೩ 15cm diameter pipe using water
at 20°C. Find the velocity and rate of flow in the model. Viscosity of water at 20°C = 0.01 poise.
9 a) The frictional torque T of a disc of diameter D rotating at a speed of N in a fluid of
(10) viscosity: and density ೧ in ೩ turbulent flow is given by T=D°N? (யம.
b) A trapezoidal channel having bottom width 6m, side slope 2H to 1 V, N=0.025 (10)
and bottom slope 0.0016 carries a discharge of 10 m?/s. Compute the back water
profile created by a dam which backs up the water to a depth of 2m immediately
behind the dam. Use the direct step method for computation.

Page 2 of 2