## Applied Hydraulics - 2 - May 2015

### 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.

### Answer any 4 of the following

**1 (a)** Explain surface profiles in open channel.(5 marks)
**1 (b)** Explain Boundary Layer separation and control measures.(5 marks)
**1 (c)** Compare Kennedy's and Lacey's theory.(5 marks)
**1 (d)** Explain specific energy curve.(5 marks)
**1 (e)** Write a note on standing wave Flume.(5 marks)
**2 (a)** A trapezoidal channel with a side slope of 1:1 has to be designed to convey 10m^{3}/sec at a velocity of 2 m/sec, so that the amount of concrete lining for the bed and sides is minimum. Calculates the area of lining required for one meter length of channel. The rugosity coefficient N=0.015, calculate the bed slope the channel for uniform flow.(10 marks)
**2 (b)** Water flows at the rate of 1m^{3}/sec along a channel of rectangular section 1.6 m in width. Calculate the critical depth. If a standing wave occurs at a point where the upstream depth is 0.2m, what would be rise in water level produced and the power lost in standing waves.(10 marks)
**3 (a)** A 1.6m wide, 5m long plate moves through stationary air of density 1.22 × 10^{-3} gm/cc and viscosity 1.8 × 10^{-4} poise at a velocity of 1.75 m/sec parallel to its length. Determine the draw force on one side of the plate. (a) Assuming laminar flow conditions, (b) Assuming turbulent flow condition.(12 marks)
**3 (b)** A kite of dimensions 0.8 × 0.8 m and weighing 6 N is maintain in air at an angel of 10° to the horizontal. The string attached to the kite makes an angel of 45° to the horizontal and at this position, the drag and lift coefficients are estimated to be 0.6 and 0.8 respectively. Determine wind speed and tension in the string.(8 marks)
**4 (a)** Water flows in a rectangular channel of 4 m width at a depth of 2.50 m and a velocity of 2.25 m/sec. If the width of channel is reduced to 2.250 m and the bed of channel is raised by 0.20 m at section, how will the level of water surface in the channel be affected?(10 marks)
**4 (b)** Design an irrigation channel in alluvial soil according to Lacey's silt theory. Given the following data, slope of channel =1:5000, Lacey's slit factor=0.9.(10 marks)
**5 (a)** Derive boundary layer thickness, local coefficient of drag and coefficient of drag for the given velocity profile

$$\dfrac{u}{U}=\dfrac{3}{2}\dfrac{\gamma }{\delta }-\dfrac{1}{2}\left ( \dfrac{\gamma }{\delta } \right )^{3}$$(15 marks)
**5 (b)** Explain discharge curve in open channel.(5 marks)
**6 (a)** A circular of 1 m diameter and 10 m length is rotated at 420 rpm about its axis when its is kept in air stream with 11.0 m see velocity perpendicular to it axis. Determine (i) Circulation around the cylinder. (ii) Theoretical lift and lift coefficient , (iii) Position of stagnation point, (iv) Actual drag and lift force on the cylinder and (v) Actual resultant force and its direction.(10 marks)
**6 (b)** Derive dynamic equation for gradually varied flow in case of wide rectangular channel. Also state assumptions made for the same.(10 marks)