Applied Hydraulics - 2 - Dec 2014

Civil Engineering (Semester 6)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks. 1 (a) Explain terminal velocity of a body with example.(5 marks) 1 (b) Explain Boundary Layer separation.(5 marks) 1 (c) Differentiate between uniform & non uniform flow, steady & unsteady flow.(5 marks) 1 (d) Derive the condition for maximum discharge for a given value of specific energy.(5 marks) 2 (a) A sewer is to be laid a slope of 1 in 8100 to carry a maximum discharge of 600 liters/sec, when depth of water is 75% of the vertical diameter. Find the diameter of the pipe. Take Manning N is 0.025.(10 marks) 2 (b) Derive the condition for most economical trapezoidal channel including best side slope.(10 marks) 3 (a) What is drag? What causes it? Why do we usually try to minimize it.(10 marks) 3 (b) Classify the surface profiles in gradually varied flow with neat sketches.(10 marks) 4 (a) Derive the Von-Karman momentum integral equation for boundary layer flows.(10 marks) 4 (b) Find the displacement thickness, the momentum thickness and energy thickness for the velocity distribution in the boundary layer given by
u/U=2(y/δ)-(y/δ)²(10 marks) 5 (a) Determine the length of the back water curve caused by an afflux of 2.0 meter in a rectangular channel of width 40 meter and depth 2.5 meter. The slope of the bed is given as 1 in 11000. Take Manning's N=0.03.(10 marks) 5 (b) A kite 0.8 m × 0.8 m weighing 4.0 N assumes an angle of 12° to the horizontal. The string attached to the kite makes an angle of 45° to the horizontal. The pull on the string is 25N, when the wind is flowing at a speed of 30 km/hr. Find the corresponding co-efficient of drag and lift. Density of air is given as 1.25kg/m³.(10 marks) 6 (a) Compare kennedy's and Lacey's slit theories. Why Lacey's conception superior to that of Kennedy's.(10 marks) 6 (b) Design an irrigation canal to carry a discharge of 14 cumes. Assume N=0.0225, m=1 and B/D=5.7.(10 marks) 7 (a) Derive the expression for loss of energy due to Hydraulic jump.(10 marks) 7 (b) Write a short note on
i) Specific Energy and specific curve.
ii) Development of lift on a Airfoil.(10 marks)