09A52401 Mechanics of Fluids & Hydraulic Machines B.Tech Question Paper : sphoorthyengg.com
Name of the College : Sphoorthy Engineering College
University : JNTUH
Department : AUTOMIBILE ENGINEERING
Subject Code/Name : 09A52401/MECHANICS OF FLUIDS AND HYDRAULIC MACHINES
Year : December 2011
Degree : B.Tech
Year/Sem : III/I
Website : sphoorthyengg.com
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/sphoorthyengg.com/4786-09A52401%20-%20MECHANICS%20OF%20FLUIDS%20AND%20HYDRAULIC%20MACHINERY.pdf
Mechanics of Fluids Question Paper :
B. Tech III Year I Semester Examinations, December-2011
(AUTOMIBILE ENGINEERING)
Time: 3 hours
Related : Sphoorthy Engineering College 09A50306 Applied Thermodynamics-II B.Tech Question Paper : www.pdfquestion.in/4844.html
Max. Marks: 75
Answer any five questions :
All questions carry equal marks :
1.a) State and explain Newton’s law of viscosity with a neat sketch and give examples of its application.
b) In a stream of glycerine in motion, at a certain point, the velocity gradient is 0.25 metre per sec per metre. The mass density of fluid is 1268.4 kg per cubic metre and kinematic viscosity is 46.3010-× square metre per second. Calculate the shear stress at the point. [7+8]
2.a) Define stream line, path line and streak line. Derive mathematical expressions for each of these lines.
b) A 75 cm diameter uniform pipe bend turns the directions of flow of gasoline of Sp.gr. 0.79 through an angle of 120° in the horizontal plane. The constant pressure and velocity through the bend are 90 KPa and 3 m/s respectively.
Find the magnitude and direction of the force to be exerted on the bend to achieve the directional change. [7+8]
3.a) Derive an expression for the loss of head due to friction in pipes.
b) The water is flowing through a pipe of diameter 30 cm. The pipe is inclined and a venturimeter is inserted in the pipe. The diameter of venturimeter at throat is 15 cm.
The difference of pressure between the inlet and throat of the venturimeter is measured by a liquid of specific gravity 0.8 in an inverted U-tube which gives a reading of 40 cm. The loss of head between the inlet and throat is 0.3 times the kinetic head of the pipe. Find the discharge. [7+8]
4.a) Show that when a jet of water impinges on a series of curved vanes, maximum efficiency is obtained when the vane is semi-circular in section and the velocity of a vane is half that of jet.
b) A 7.5 cm diameter jet having a velocity of 30 m/s strikes a flat plate, the normal of which is inclined at 450 to the axis of the jet. Find the normal force exerted on the plate.
i) When plate is stationary
ii) When plate is moving with a velocity of 15 m/s in the direction of jet away from the jet. Also determine the power and efficiency of system when the plate is moving. [7+8]
5.a) Distinguish between
i) Base load power plant and a Peak load power plant
ii) Firm power and Secondary power.
b) A run-off- river plant is installed on a river having a minimum flow of 11m3/sec. If the plant is used as a peak load plant operating only for 5 hours a day, determine the firm capacity of the plant (a) without pondage (b) with pondage but allowing 10% of the water to be lost in evaporation and other losses. Head at the plant is 16m and the plant efficiency may be assumed as 75%. [7+8]
6.a) Compare and contrast impulse and reaction turbines.
b) The following data refers to a Pelton wheel installation: net head = 250 m, speed ratio = 0.45, nozzle coefficient = 0.98, jet ratio = 18, overall efficiency = 76%, frequency of generation = 50 Hz and pairs of poles of alternator = 6. Compute the wheel diameter, jet diameter and the power output in KW. [7+8]
7.a) Derive expressions for the following unit quantities of a hydraulic turbine:
i) unit speed, ii) unit discharge and iii) unit power.
b) A prototype Kaplan turbine develops 7500 KW under a head of 10 m. The speed is 100 rpm. The head on a 1:10 reduced scale model is 4 m. Assuming the same efficiency of 85% for both model and prototype, find Q, P, N and Ns of the model. [7+8]
8.a) Draw the following characteristic curves for a centrifugal pump. Head, Power and Efficiency versus discharge with constant speed.
b) A centrifugal pump having outer diameter equal to two times the inner diameter and running at 1200 r.p.m. works against a total head of 75m. The velocity of flow through the impeller is constant and equal to 3 m/s.
The vanes are set back at an angle of at outlet. If the outer diameter of the impeller is 600 mm and width at outlet is 50 mm, determine: 030
a) Vane angle at inlet,
b) Work done per second by impeller,
c) Manometric efficiency. [7+8]