Name of the College : P.E.S College of Engineering
University : Visvesvaraya Technological University
Department : Mechanical Engineering
Subject Code/Name : P08ME45/Fluid Mechanics
Degree : B.E
Sem : IV
Website : pescemandya.org
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/pescemandya.org/4693-mech_question_paper.pdf
PESE Fluid Mechanics Model Question Paper
Fourth semester B. E Degree Examination
Time: 3 hrs
Max. Marks: 100
Related : P.E.S College of Engineering P08ME43 Mechanical Measurements & Metrology B.E Model Question Paper : www.pdfquestion.in/4692.html
Note: Answer any FIVE full questions Selecting at least two questions from each part.
PART-A
1. a Give reasons for the following:
The meniscus of water is concave upwards while the meniscus of mereury is convex upwards.
Viscosity of llqulds decrease on heating whereas viscosity of gases increase on heating.
Rain drops and tiny dew drops are spherical in shape. (06 Marks)
b A vertical gap 2.2cm wide of infinite extent contains a fluid of viscosity 2.0NS/m2 and specific gravity 0.9. a metallic plate 1.2mX1.2mX0.2cm is to be lifted up with a constant velocity of 0.15m/sec, through the gap. If the plate is in the middle of the gap, find the force required. The weight of the plate is 40 N. (10 Marks)
c Two liters of petrol weighs 14N. Calculate specific weight, mass density, specific volume and specific graving of petrol. (04 Marks)
2. a Obtain an expression for the pressure and depth of center of pressure in case of an inclined immersed surface. (10 Marks)
b A U-tube manometer is used to measure the pressure of water in a pipe the which is in excess of atmospheric pressure. The right limb of the manometer contains mercury and is open to atmosphere. The contact between water and mercury is in the left limb.
Determine the pressure of water in the main line, if the difference in level of mercury in the limbs of U-tube is 10 cm and the free surface of mercury is in level with the center of the pipe, if the pressure of water in pipe line is reduced to 9810 N / m2.
Calculate the new difference in level of mercury. Sketch the arrangements in both the cases. (10 Marks)
3. a Distinguish between: i) steady and unsteady flow ii) Uniform and non uniform flow. (04 Marks)
b Derive the continuity equation in 3 dimensions for a steady incompressible flow. (06 Marks)
c The stream function for a two-dimentional flow is given by ?= 3xy. Calculate the velocity at point A (3, 4). Also find the velocity potential function f. (10 Marks)
4. a Explain the terms: i) Geometric similarity ii) Kinematic similarity iii) Dimensional homogeneity. (06 Marks)
b Define i) FROUDE Number ii) WEBER Number iii) Euler Number iv) Mach Number. (04Marks)
c The resisting force R of supersonic plane during flight can be considered as dependent upon the lenigh of the aircraft l, velocity V, air viscosity , air density and bulk modulus of air K. Express the functional relationship between these variables and the resisting force by using buckingham’s theorem.(10 Marks)
PART-B
5. a State the principal of working of a venturimeter and obtain an expression for the actual discharge through the venturimeter. (08 Marks)
b A pipe line carrying oil of specific gravity 0.87 changes in diameter from 200mm diameter at a position A to 500mm diameter at a position B which is 4 meters at a higher level. If the pressure at A and B are 9.81 N/cm2 and 5.886N/cm2 respectively and the discharge is 200 litres/ sec, determine the loss of head and direction of flow. (10 Marks)
c State the working principle of pitot tube. (02 Marks)
6. a Define upper critical and lower critical Reynold’s Number. (02 Marks)
b Show that for laminar flow through a circular pipe . (10 Marks)
c A fluid of viscosity 0.7N sec/m2 and specific gravity 1.3 flowing through a circular pipe of diameter 100mm. the maximum shear stress at the pipe wall is given as 196.2 N/m2. Find i) the pressure gradient ii) the average velocity and iii) Reynold’s number. (08 Marks)