Jawaharlal Nehru Technological University Hyderabad 2011-1st Year B.E Electrical and Electronics Engineering I B.TECH - FLUID MECHANICS AND HYDRAULIC MACHINERY (EEE) - Question Paper

B.TECH - I SEMESTER exams - MAY, 2011
FLUID MECHANICS AND HYDRAULIC MACHINERY
(ELECTRICAL AND ELECTRONICS ENGINEERING)
Time: 3hours Max. Marks: 75
ans any 5 ques.
All ques. Carry Equal Marks
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1.a) Differentiate
i) Real fluids & Ideal fluids
ii) Newtonian & non Newtonian fluids.
Through a narrow gap of height d, a thin plate of large surface is pulled with a velocity U on 1 side of the plate, oil is of velocity µ1, and on the other side of µ2. Determine the position of the plate so that the shear force on 2 sides is equal.
b) What is the difference ranging from U – tube differential monometer and inverted U – tube differential manometer?
For the arrangement shown in figure, determine the height 'H'. [7+8]
2.a) Distinguish ranging from stream lines, streak lines & path lines the flow field is provided by
? = x3y check weather the provided field exist or not? Further check whether it is irrotational?
b) Water flows through a 0.9m diameter pipe at the end of which there is reduction connecting to a 0.6m diameter pipe. If the gage pressure at the entrance decreases to 412.02 kN/m2 and the velocity is 2m/s, determine the resulting thrust, assuming that the frictional; loss of head in the decreases is 1.5m. [7+8]
3.a) Derive an expression for loss of head due to sudden expansion in pipe line with usual notation.



b) With a neat sketch discuss the working principle of pilot tube. A venturimeter has its axis vertical, the inlet and throat diameter being 150 mm and 75 mm respectively. The throat is 225 mm above inlet and K = 0.96. Petrol of specific gravity 0.78 flows up through the meter at a rate of 0.029 m3/s. obtain the pressure difference ranging from the inlet and the throat. [7+8]
4.a) find the relation ranging from the velocity of jet and the velocity of the vane to find the maximum efficiency, when a jet of water impinges on a series of vanes mounted on the circumference of a wheel at a fixed distance apart.
b) A jet of water having a velocity of 20 m/s strikes a curved vane which is moving with a velocity 9m/s. The vane at inlet and lever at an angle 1300 to the direction of motion of the vane and outlet, compute the work done per 2nd per kg of water. Strikes the vane. [7+8]
5.a) Differentiate ranging from storage and pondage supply your ans with a neat sketch.
b) What is mass curve? discuss the procedure for preparing a mass curve and also its uses. [7+8]
6.a) The pelton wheel has the water head 5.6 m. If the speed ratio = 2.09 flow ratio = 0.68 overall efficiency 86% and the diameter of the boss is 1/3 the diameter of the runner. obtain the diameter of the runner, its speed of and the specific speed of the turbine.
b) find an expression for the work done per 2nd by water on the runner of the
pelton wheel. Hence derive an expression for maximum efficiency [7+8]
7.a) Derive an expression for specific speed of turbine. What is its significance in the design of turbine?
b) Water is flowing in a long pipe which is 0.15 m diameter and 6.25 mm thick with a velocity of 1.2 m/s and it is suddenly brought to rest by the closing of a valve. compute the inertia pressure and the theoretical stress produces in the pipe near the valve, taking K for water as 207×104 kN/m2 and E for pipe material as 206×106 kN/m2. [7+8]
8.a) describe NPSH and derive the formula for the identical. Why pump industry specifies NPSH for pumps. What is its significance?
b) A water pump has to deliver 20 lit/s of water when running at 1200 rpm. The inlet vane angle is 300 and exit vane angle is 450. If the velocity of flow is constant in the impeller, the power supplied to run the pump by the motor is 40 kW. Assuming the mechanical efficiency as 0.9 final inlet and outlet diameters of the impeller.
Take D2 = 2d. [7+8]

Earning:   Approval pending.