QUESTION BANK FOR FLUID MECHANICS UPTU UNIVERSITY

-
                                                         
                                                                 Unit-1

1.Define the following
a. surface tension    b. viscosity    c. specific density    d. Vapour pressure   e. centre of pressure
f. centre of buoyancy   g. metacentre  h. metacentric height

2. A metallic body floats at interface of mercury of specific gravity 13.6 and water in such a way that 30% of its volume is submerged in mercury and 70% in water .find density of the metallic body.

3.state the Newton’s law of viscosity .Explain importance of viscosity in fluid motion .what is effect of temperature on viscosity of water and that of air.

4. Define surface tension .Establish relationship among surface tension .pressure within the droplet of liquid in excess of outside pressure and diameter of droplet.

5. What is meant by stability of a floating body ? Explain with reference to its meta centre height with the help of neat sketches.

6. Determine the total pressure on a circular plate of diameter 1.5m which is place vertically in water in such a way that centre of  plate is 3m below the free surface of water .Find the position of centre of pressure also.

7.A solid cylinder of 2m diameter and 2m height is floating in water with its axis vertical if the specific gravity of the cylinder is 0.65 , find its meta centric height and state whether the equilibrium is stable or unstable.

8.Explain the phenomenon of capillary. Derive an expression for capillary rise or fall when a small diameter tube dipped into a liquid.

9. A capillary tube of diameter 1.5 mm is dipped in  (i) water (ii) Mercury .Find the capillary rise for each case .surface tension for water and mercury may be taken as 0.075 N/m and 0.52 N/m respectively .The contact angle may be taken as zero and 1300 for the two cases respectively.

10. Define the non-Newtonian fluid ? Describe the rheology of fluid with example ?

11. State the Hydrostatics law .derive the derivation for hydrostatic law with suitable diagram.




                                                             Unit-2

1 . Define stream function and velocity potential function .prove that streams lines and  equipotential lines meet each other orthogonally.

2. Derive an expression of continuity equation of fluid flow in 3D with neat sketches.

3.Explain the terms
(i) Path line  (ii) streak line  (iii) stream line

4.Explain the types of fluid flow with neat sketches.

5.What do you understand by the terms (i) convective acceleration  (ii) local acceleration

6. Write short notes on;
 (i) source  (ii) sink  (iii) doublet

7. A stream function in a two –dimensional flow is   =2xy .Determine the corresponding velocity potential  .

8.Define the circulation .find the circulation around a closed curve defined by
Y=1, x=2, y=4 , and x=4
When the velocity field is given by U=16y-8x    , V=8y-7x

9.A stream function is given by  =3xy Determine
i) whether the flow is possible
ii)Whether the flow is rotational or irrotational.
iii) The potential function
iv) Acceleration component at (1,1)

10. Write down the assumption made in the continuity equation.


                                                         Unit-3

1.State the Assumption made in the Bernoulli Equation .

2.State and prove Bernoulli equation with neat diagram.

3. A pipe line carrying oil of specific gravity 0.87 changes in diameter from 200mm diameter at a     position A to 500 mm diameter at a position B which is 4 m at a higher level .if the pressure at A and B  are 9.81 N/cm2  and 5.886 N/cm2 respectively and the discharge is 200 litre/sec. Determine the loss of head and direction of flow.

4.  Define and discuss hydraulic gradient line and total energy line with figure

5. Explain water hammer with neat diagram ?

6. A 1: 75 model of a submarine is tested in water .What is the speed of the model to simulate a speed of 3 m/sec of the submarine .

7. What do you mean by distorted and undistorted model ? Explain the advantage of distorted model

8. Derive an expression for the discharge over a triangular notch with suitable diagram ?

9. Describe momentum Equation .where this equation is used ?

10. A pipe bend of 400mm at the inlet and 200mm at the outlet turns the flow of water through 1200 in a vertical plane. The flow through the bend is 200 lit/sec.and the pressure at the inlet is horizontal and th exit is 1.2m below the entrance section. If the voloume of the bend is 0.18 m3 determine the force exerted on the bend.

11.Three pipes of 800m, 500m and 300m of diameters 50cm ,30 cm ,and 40cm respectively are connected in series if these pipes are to be replace by a single pipe of 2000m long. find the required diameter Consider f is same of all pipes and all the minor losses are neglected
.
12.A venturi meter 100 mmx50 mm size is used to measure the flow of liquid of specific gravity 0.8 if the mercury differential manometer head is 200 mm .Find the discharge through the venturimeter .Find also absolute pressure at the neck if the pressure at the enlarge end is 0.5 kg/cm2 take cd =0.98
8.Derive the derivation for discharge through venturimeter with neat sketch.

 13. What are the major and minor losses in a pipe flow ?
14 .What do you mean by dimensional less number ? Name any four dimensionless number and its practical application in fluid mechanics ?
15. State Buckingham  theorem .What are  the repeating variable ? How are these selected in dimensional analysis ?
16. if 300m length of 200mm diameter pipe with friction factor 0.018 is to be replaced      by 150 mm diameter pipe with friction 0.02 to carry the same discharge .what length will have to be provided ?
17. Find the discharge through  a trapezoidal notch which is 1.2 m wide at top and    0.5 m at the bottom and is 40 cm in height , The head of water on notch is 30 cm. Assume  cd for rectangular portion as 0.62 while for triangular portion as 0.62.
18. What is pitot tube ? How is it used to measure velocity of flow at any point in pipe         channel ?




                                                            UNIT-4

1. Prove that laminar flow through a circular pipe momentum correction factor  =4/3.
2.Explain the concept of mixing length introduced by prandtl and state the relationship that exist between the turbulent shearing stress and the mixing length.
3.Give the classification of boundaries based on roughness height with neat sketch.
4.What do you understand by turbulent flow ? Find an expression for shear stress due to prandtl.
5.A pipe of 10 cm diameter carries water .The velocities at the pipe centre and 3 cm from the pipe centre 2 m/s and 1.5 m/s respectively .if the flow in the pipe is turbulent determine the shear stress at the pipe wall at 3 cm from the pipe wall.


6.For laminar flow of an oil having dynamic viscosity =1.766Pa.s in a 0.3 diameter pipe flows with a maximum central line velocity of 3 m/s. Calculate shearing stresses at the pipe wall and within the fluid 50 mm from the pipe wall
7.Using stokes law derive an expression for the terminal velocity for a sphere falling in a liquid .Also state the assumption.
8.find the expression for pressure drop for a given length of a pipe in a laminar flow.
9.Define the kinetic correction factor and momentum correction factor ?
10.Differentiate between laminar and turbulent flow


                                                              Unit-5

1. What is boundary layer ? Explain with a neat sketch the development of boundary layer over   a  smooth flat plate ?
2. A kite 0.8 m x 0.8 m and weighing 4 N is maintained in air at an angle of 100 to the horizontal The string attached to the kite makes an angle of 450 to the horizontal and at this position the values of coefficient of drag and lift are 0.6 and 0.8 respectively. Find the speed of the wind tension in the string .Take density of air=1.25 kg/m3
3.Differentiate between stream line body and bluff body.
4.What is boundary layer separation ? what are the preventive measures to control it ?
5.Explain the concept of boundary layer .What do you mean by laminar ,transition and turbulent boundary layer ? Explain with the help of neat sketch. what is laminar sub layer.
6.what do you understand by displacement thickness and momentum thickness ?
7.write a short notes on the following terms
a. Magnus effect     b. Aerofoil    c. coefficient of lift      d. coefficient of drag

8.For the velocity distribution for laminar boundary layer flows given as


 Find the expression for boundary layer thickness (  ) shear stress (  ) and coefficient of drag in     terms of Reynolds number .

9 .Define displacement thickness. Derive an expression for the momentum thickness for boundary layer flow.
10. Differentiate between free and forced vortex flow ?

Comments

Post a Comment

Popular posts from this blog

QUESTION BANK OF MACHINE DESIGN II FOR UPTU

-
                                                  UNIT-1  1. Derive the expression of beam strength of a spur gear tooth.  2. Derive the expression for efficiency of worm wheel drive.  3. What is virtual or formative gear?   4. Describe the law of gearing. Why involute teeth are preferred over cycloidal teeth? What is the reason of interference in gears and how it can be avoided?  5. Using a suitable schematic diagram explain the forces acting on worm gears. Also, define normal pitch, helix angle and efficiency of worm gear drive.  6. Briefly discuss the following: (i) System of gear teeth (ii) Pressure angle  7. Discuss the classification of helical gears.  With a neat sketch explain the forces acting on a helical gear and explain.  8. With the help of a sketch, explain how an axial thrus...
Read more

strength of material question

-
1.if arod expand freely due to heating .it will develop. a.Bending stress b.Thermal stress c.No stress d.compressive stress 2.materials which show direction dependent properties are called a.homogenious b.viscoelastic c.isotropic d.anisotropic 3.if apiece of material neither expand nor contract in volume when subjected to stress then the  poisson ratio must be a.zero b..25 c..33 d..5 4.what is the relationship between elastic constants E,G, and K a.E=KG/9K+G b.E=9KG/K+G c.E=9KG/K+3G d.E=9KG/3K+G 5.maxium shear stress in a mohrs circle a.is equal to radius of mohrs circle b.is greater than radius of mohrs circle c.is less than radius of mohrs circle d.could be aby the above.
Read more

tips for gate exam

-
1. Uniqueness in their study material: Study material provided by the coaching institutes is of little assistance if they are compact copy-paste or rewrite of materials taken from other books. If the reading of such material doesn’t increase interest and enjoyment then they are not worth it. There are plenty of standard books on each subject by good authors, which can make your study enjoyable during preparation. 2. Collection of quality books in their library: During the process of theory conceptualization and building application capabilities, you need good books, which can really put your brain on exercise. Check out their library! 3. Flexibility in the Coaching Model: What happens when your pace of learning is much faster or slower than the average? Is there any mechanism by which the model can identify exactly where you need help and provide the same? Is it possible in that coaching model to minimize the wastage of your time? 4. Quality of questions discussed: Number of questions...
Read more