Jawaharlal Nehru Technological University Kakinada 2008 B.Tech Electrical and Electronics Engineering FLUID MECHANICS AND HYDRAULIC MACHINERY - Question Paper

Code No: 07A3EC02 Set No. 1
II B.Tech I Semester Regular Examinations, November 2008
FLUID MECHANICS AND HYDRAULIC MACHINERY
( Common to Electrical & Electronic Engineering and Production
Engineering)
Time: three hours Max Marks: 80
ans any 5 ques.
All ques. carry equal marks
? ? ? ? ?
1. (a) explain the in?uence of the subsequent ?uid properties on ?uid motion
i. Viscosity
ii. Speci?c gravity
iii. Surface tension
iv. Bulk modulus
(b) If the surface tension at air water interface is 0.073N/m, What is the pressure
di?erence ranging from inside and outside of an air bubble of diameter 0.01mm?
[10+6]
2. (a) define stream line and stream tube with the help of neat sketches.
(b) For steady incompressible ?ow verify whether the subsequent values of u and v
are possible:
i. u = 4xy + y2
, v = 6xy + 3x
ii. u = 2x2
+ y2
, v = -4xy
iii. u = -x/ (x2
+ y2
), v = -y/(x2
+ y2
). [6+10]
3. (a) elaborate the construction details of a pitot tube and discuss how it works?
(b) An oil of relative density 0.90 ?ows through a vertical pipe of diameter 20cm.
The ?ow is measured by a 20cm × 10cm venturimeter. The throat is 30cm
above the inlet part. A di?erential U tube manometer containing mercury
is connected to the throat and the inlet. If coe?cient of discharge is 0.99 what
is the manometer studying for a ?ow of 50 lit/sec. [6+10]
4. (a) A nozzle of 56 mm diameter delivers a stream of water at 30 m/sec perpen-
dicular to a plate that moves away from the jet at eight m/sec. obtain the work
done and e?ciency of the jet.
(b) Prove that the force exerted by a jet of water on a ?xed curved vane when the
jet strikes at the centre is F = ?av2
(1+cos?) where
? = Mass density of water
a = Area of cross part of the jet
v = Velocity of the jet
? = Angle of the curved plate at the out let. [8+8]
5. (a) discuss the inherent advantages, which make Hydropower more attractive.
1 of 2Code No: 07A3EC02 Set No. 1
(b) A runo? stream with an installed capacity of 12000KW operates at 15% load
factor when it serves as a peak load station. What should be the least
discharge in the stream so that the station may serve as the base load station.
It is provided that plant e?ciency is 70% when working under a head of 18m.
Also compute maximum load factor of the plant when the discharge in the
stream rises to 18 cumecs [8+8]
6. (a) De?ne the terms: speed ratio, ?ow ratio and jet ratio
(b) An inward ?ow reaction turbine has external and internal diameters as 1.2 m
and 0.6 m respectively. The velocity of ?ow through the runner is constant

Earning:   Approval pending.