2 markQuestions
1.
Define fluid.
2.
Give the expression for bernoullis’s Equations of
motion.
3.
Define specific weight.
4.
Define capillary action in pitot tube.
5.
List few minor energy losses in a pipe line.
6.
What are the advantages of using Buckingham’s p - theorem.
7.
What is meant by geometric similarity?
8.
Basic working principle of a centrifugal pump..
9.
What is the specific speed in a Pelton wheel?
10. What
is indicator diagram in a centrifugal pump?
12. Define
non Newtonian fluid.
13. Differentiate
between fluid and solid.
14. Define Specific
volume
15. Define
Specific gravity.
16. Define
Viscosity.
17. Define
Compressibility.
18. Define vapour pressure.
19. Write eulers equation in a strem line moion.
20. Define Capillarity.
21. Define Surface tension.
22. What is darcy weisback equation.
23. Differentiate between Absolute and gauge
pressures.
24. Mention
two pressure measuring instruments.
25. What
is peizometer?
26. How
manometers are classified.
27. What
is pitot static tube?
28. Write
down the units for dynamic and kinematic viscosity.
29. State
Newton’s law of viscosity.
30. Differentiate
between Newtonian and non Newtonian fluid.
31. Differentiate
between ideal and real fluid.
32. What
is ideal plastic fluid?
33. Define
velocity gradient.
34. What
is the difference weight density and mass density?
35. What
is the difference between dynamic and kinematic viscosity?
36. Differentiate
between specific weight and specific volume.
37. Define
relative density.
38. What
is vacuum pressure?
39. What
is absolute zero pressure?
40. Write
down the value of atmospheric pressure head in terms of water and Hg.
41. Define
stream line.
42. Define
path line.
43. Define
streak line.
44. Define
steady flow.
45. Define
uniform flow.
46. Differentiate
between laminar and turbulent flow.
47. How
will you classify the flow as laminar and turbulent.
48. Differentiate
between compressible and incompressible flow.
49. Differentiate between rotational and
irrotational flow.
50. Define
stream function.
51. Define
velocity potential function.
52. Write
down continuity equation for compressible and incompressible fluid.
53. Write
down continuity equation in three dimensions.
54. Differentiate
between local and convective acceleration.
55. Define
circulation.
56. Define
flow net.
57. Write
down Euler’s equation of motion.
58. Write
down Bernoulli’s equation of motion for ideal and real fluid.
59. State
the assumptions made in Bernoulli’s equation of motion.
60. Mention
the applications of Bernoulli’s equation of motion.
61. Mention few discharge measuring devices.
62. Classify
pumps
63. What
is meant by indicator diagram?
64. Define
boundary layer.
65. Define
turbulent flow.
16
markQuestions
1.
A jet of water coming out of nozzle at a velocity of 35m/sec strikes a series
of vanes without shock which are moving with a velocity of 10m/sec. The
direction of jet is 200 to
the motion of vanes. The relative velocity of jet at outlet is 0.9 times
relative velocity at inlet. The absolute velocity of jet at outlet is normal to
the motion of vanes. Find
(a)
the inlet and exit vane angles,
(b)
work done
(c)
Efficiency of the system. [16]
2.
A water tube has a velocity of 4m/sec at the entrance to the draft tube and a
velocity
of 1.2m/sec at the exit. For Friction losses of 0.1m and a tail water 5m
below
the entrance to the draft tube, find the pressure head at the entrance. [16]
3.
(a) What is meant by cavitation? What is Thomas cavitation factor and what is
its
significance for water turbines.
(b)
Explain Iso-efficiency curves. [8+8]
4.
(a) Why is the speed of a reciprocating pump lower than that of a centrifugal
pump?
On what factors does the speed of the reciprocating pump depend?
(b)
Explain how the separation of flow is caused in reciprocating pumps. What
preventive
measures are usually taken to reduce the same appreciably? [8+8]
5.
(a) How will you obtain an expression for the minimum speed for starting a cen-
trifugal
pump?
(b)
The internal and external diameter of the impeller of a centrifugal pump are
200
mm and 400 mm respectively. The pump is running at 1200 r.p.m. the
vane
angles of the impeller at inlet and outlet are 20o and 30o respectively. The
water
enters the impeller radially and velocity of flow is constant. Determine
the
work done by the impeller per unit weight of water. [6+10]
6.
(a) What do you understand by characteristic curves of a pump? What is the
significance
of the characteristic curves.
(b)
Find the number of pumps required to take water from a deep well under a
total
head of 89 m. All the pumps are identical and are running at 800 r.p.m.
the
specific speed of each pump is given as 25 while the rated capacity of each
pump
is 0.16 m3/s.
7.
The diameter of ram of a jigger of the crane is 30 cm and velocity ratio of the
crane
is
5 : 1. the length of supply pipe from accumulator = 150 m and its diameter is
5
cm. the pressure in the accumulator = 54 bar. Friction on ram and pulley is
equivalent
to a pressure of 4.9 bar. Take f = 0.01. Find the relation between the
load
W (kN) lifted and speed of lifting V (m/s). Find V when W = 50 kN. [16]
8.
(a) A pipe of diameter 300 mm and length 3500 m is used for the transmission of
power
by water. The total head at the inlet of the pipe is 500 m. Find the
maximum
power available at the outlet of the pipe, if the value of f=0.006.
(b)
A nozzle is fitted at the end of a pipe of length 300 m and of diameter
100
mm. For the maximum transmission of power through the nozzle, find
the
diameter of nozzle. Take f = 0.009. [8+8]
1.
(a) Find an expression for the efficiency of a series of moving curved vanes
when
a
jet of water strikes the vanes at one of its tips.
(b)
A jet of water of diameter 65 mm moving with a velocity of 30m/s, strikes a
curved
fixed plate tangentially at one end at an angle of 300 to the horizontal.
The
jet leaves the plate at an angle of 180 to the horizontal. Find the force
exerted
by the jet on the plate in the horizontal and vertical directions. [8+8]
2.
An inward flow reaction turbine has outer and inner diameters of the wheel as 1
m
and
0.5 m respectively. The vanes are radial at inlet and the discharge is radial.
Water
enters the vanes at an angle of 100. Assuming the velocity of flow as 3 m/s
and
constant, find the speed of the wheel and the vane angle at outlet. [16]
3.
Define cavitation. What factors a_ect occurrence of cavitation in turbines.
What
measures
are to be taken to prevent it? If cavitation were to occur, at what locations
the
cavitation damage is likely to take place. [16]
4.
Derive expressions for the accelerations and friction head impressed on the
water in
the
suction and delivery pipes. Sketch indicator diagram and determine the work
done
per stroke of the pump. [16]
5.
(a) What do you mean by manometric efficiency, mechanical efficiency and
overall
e_ciency
of a centrifugal pump.
(b)
A centrifugal pump is to discharge 0.118 m3/s at a speed of 1450 r.p.m against
a
head of 25 m. The impeller diameter is 250 mm, its width at outlet is 50
mm
and manometric efficiency is 75%. Determine the vane angles at the outer
periphery
of the impeller. [8+8]
6.
(a) What is cavitation? State its effect on the performance of water turbines
and
also
state how to prevent cavitation in water turbines.
(b)
Find the rise in pressure in the impeller of a centrifugal pump through which
water
is flowing at the rate of 0.01 m3/s. The internal and external diameter
of
the impeller are 15 cm and 30 cm respectively. The widths of the impeller
at
inlet and outlet are 1.2 cm and 0.6 cm. The pump is running at 1500
r.p.m.
The water enters the impeller radially at inlet and impeller vane angle
at
outlet is 45o. Neglect losses through the impeller. [6+10]
7.
(a) A hydraulic lift is required to lift a load of 98.1kN through a height of
12 m,
once
in every 100 seconds. The speed of the lift is 600 mm/s. Determine:
i.
power required to drive the lift,
ii.
working period of lift in seconds, and
iii.
idle period of the lift in seconds.
(b)
What is hydraulic intensifier? Explain its principle and working. [10+6]
8.
(a) A pipe of diameter 300 mm and length 3500 m is used for the transmission of
power
by water. The total head at the inlet of the pipe is 500 m. Find the
maximum
power available at the outlet of the pipe, if the value of f=0.006.
(b)
A nozzle is fitted at the end of a pipe of length 300 m and of diameter
100
mm. For the maximum transmission of power through the nozzle, find
the
diameter of nozzle. Take f = 0.009. [8+8]
1.
5 cm diameter jet having a velocity of 20m/sec, strikes a flat plate, the
normal of
which
is inclined at 250 to the axis of the jet. Calculate the normal force exerted
on
the plate
(a)
When the plate is stationary
(b)
When the plate is moving with a velocity of 10m/sec in the direction of the
jet.
(c)
When the plate is moving with a velocity of 7m/sec parallel to itself and in
the
direction of the normal to its surface. [4+6+6]
2.
Obtain an expression for the work done per second by water on the runner of a
Pelton
wheel. Hence derive an expression for maximum e_ciency of the Pelton
wheel
giving the relationship between the jet speed and the bucket speed. [16]
3.
(a) Define Suction Specific Speed. Explain the procedure for the selection of
type
of
turbine runner.
(b)
List out di_erent types of surge tanks and explain any two along with neat
sketches.
[8+8]
4.
A double acting reciprocating pump has a stroke of 250mm and plunger diameter
125
mm. The center of the pump is 4 m above the lower sump water level and 30
m
below the delivery water. The lengths of suction and delivery pipes are 6 m and
35
m respectively. Both pipes are 60 mm in diameter. If the pump is to run at
30
rpm, find the pressure head on the piston, at the beginning, middle and end of
the
suction stroke. If mechanical e_ciency is 75% and f=0.04, determine the power
required
to drive the pump. [16]
5.
The outer diameter of an impeller of a centrifugal pump is 400 mm and outlet
width
50 mm. The pump is running at 800 r.p.m and is working against a total
head
of 15 m. The vanes angle at outlet is 40o and manometric e_ciency is 75%.
Determine:
(a)
velocity of flow at outlet
(b)
velocity of water leaving the vane,
(c)
angle made by the absolute velocity at outlet with the direction of motion at
outlet,
and
(d)
discharge.
6.
(a) Draw and discuss the operating charecteristcs of a centrifugal pump.
(b)
Two geometrically similar pumps are running at the same speed of 1000 r.p.m.
One
pump has an impeller diameter of 0.3 meter and lifts water at the rate
of
20 liters per second against a head of 15 meters. Determine the head and
impeller
diameter of the other pump to deliver half the discharge. [6+10]
7.
(a) How does a torque convertor di_er from a fluid coupling? Explain the
working
principle
of any one of them.
(b)
A hydraulic lift is required to lift a load of 8 kN through a height of 10
meters,
once
in every 80 seconds. The speed of the lift is 0.5 m per second. Determine:
i.
Power required to drive the lift,
ii.
Working period of lift in seconds, and
iii.
Idle period of the lift in seconds. [8+8]
8.
(a) A pipe of diameter 300 mm and length 3500 m is used for the transmission of
power
by water. The total head at the inlet of the pipe is 500 m. Find the
maximum
power available at the outlet of the pipe, if the value of f=0.006.
(b)
A nozzle is fitted at the end of a pipe of length 300 m and of diameter
100
mm. For the maximum transmission of power through the nozzle, find
the
diameter of nozzle. Take f = 0.009. [8+8]
1.
(a) Show that the force exerted by a jet of water on moving inclined plate in
the
direction
of jet is given by Fx = ρa (V - u)2 sin2 θ, where a=area of the jet,
θ=inclination
of the plate with the jet, V=velocity of jet, u=velocity of plate
(b)
A jet of water of diameter 100mm moving with a velocity of 25m/sec strikes
a
curved fixed symmetrical plate at the center. Find the force exerted by the
jet
of water in the direction of the jet, if the jet is deflected through an angle
of
1200 at the outlet of the curved plate. [8+8]
2.
(a) Draw a neat diagram of a reaction turbine and explain its working. State
the
equations
for power produced and e_ciency.
(b)
Explain any two types of draft tubes with neat diagrams. [8+8]
3.
What do you understand by characteristic curves of a turbine? Explain various
types
of characteristic curves of a turbine along with neat sketches. [16]
4.
(a) List out eight differences between centrifugal pumps and reciprocating
pumps.
(b)
Differentiate between
i.
single acting and double acting reciprocating pump
ii.
single cylinder and double cylinder reciprocating pump. [8+8]
5.
(a) What do you mean by manometric efficiency, mechanical efficiency and
overall
efficiency
of a centrifugal pump.
(b)
The diameters of an impeller of a centrifugal pump at inlet and outlet are
20
cm and 40 cm respectively. Determine the minimum speed for starting the
pump
if it works against head of 25 m. [8+8]
6.
A one-fifth scale model of pump was tested in a laboratory at 1000 r.p.m. the
head
developed
and power input at the best efficiency point were found to be 8 m and
30
kW respectively. If the prototype pump has to work against a head of 25 m,
determine
its working speed, the power required to drive it and the ratio of the
flow
rates handled by the two pumps. [16]
7.
(a) Water at a pressure of 8 bar is supplied to a crane for lifting a weight
through
a
height of 8 m. The diameter of the ram is 16 cm and velocity ratio 5.
Assuming
the e_ciency of the crane 70%, find:
i.
The weight lifted by the crane, and
ii.
Volume of water supplied to the crane.
(b)
Draw a neat diagram of a hydraulic press and explain its working. [8+8]
8.
(a) A pipe line is 30 cm in diameter for first 1000 m. length and 15 cm
diameter for
next
1000 m. Find the discharge from the system for transmitting maximum
power.
Total pressure at the intake 5.5 kN/m2. Take f = 0.008 for both pipes.
(b)
Determine the maximum power available at the exit of the pipe of 30 cm
diameter
and 3500 m long. The head at the inlet is 500m. Take f = 0.006.
[8+8]
No comments:
Post a Comment