JNTU Question Papers Prime Movers and Mechanical Measurements 1st Sem Nov 2008
JNTU Question Papers
Prime Movers and Mechanical Measurements 1st Sem Nov 2008
1. (a) What are the types of draft tubes ? With which type of turbines are they used?
(b) A Francis turbine develops 400 bhp under a head of 24m. The inlet and exit
diameters of the runner are 1.5m and 90 cm respectively. The angle of the guide vanes is 18 degrees and the runner blades are radial at inlet. Velocity of flow is constant and no whirl velocity exists at the outlet. Find the specific speed of the turbine. [6+10]
2. (a) Why will the centrifugal pump function only when started at or above minimum speed?
(b) The centrifugal pump discharges 0.2 m3/sec against a head of 25m running at 1400 rpm. The outer diameter of impeller is 25 cm and outer width is 4 cm.
Determine the vane angle at outlet if manometric efficiency is 80%. The blade is backward facing. [6+10]
3. Explain in detail the different aspects upon which boilers are classified. 
4. The blade speed of a single ring of impulse blading is 245 m/sec and the nozzle angle is 200. The heat drop is 725kJ/kg and the nozzle efficiency is 85%. The blade discharge angle is 300 and the turbine develops 30 kW when consuming 320 kg/hr of steam. Calculate
(a) axial thrust in the blading
(b) heat equivalent of friction per kg of steam
(c) blade velocity coefficient
(d) stage efficiency. 
5. (a) Draw the regenerative gas turbine power cycle and derive its efficiency?
(b) Discuss the uses of gas turbines? [10+6]
6. Calculate the flow rate of water through a 10 cm pipe with an Orifice of 5 cm as restriction. The orifice is arranged for flange taps and a mercury manometerreads 30cm Hg at 270C.The temperature of flow water is 330C. Assume ?=0.00052 kg/ms. 
7. (a) Explain how a proving ring is used to measure force .
(b) Explain about phase shift in the seismic vibrometer. [8+8]
8. (a) Sketch the schematic arrangement of an oscilloscope for frequency and phase measurements and explain its working principle.
(b) An oscilloscope displays a sine wave and the distance between the first and fourth peaks is found to be 5.4cm. If the time base setting is 20 x 10 ?03 make
calculations for the periodic time and frequency of the sine wave.
JNTU Electrical and Electronics Measurements Exam Paper Nov 2008