STUPIDSID
1 (a)
Define turbo machine. Classify them on basis of work transfer.
4 M
1 (b)
Define the.following efficiencies of power absorbing turbo machines:
i) Total-to-total efficiency.
ii) Static-to-static efficiency
i) Total-to-total efficiency.
ii) Static-to-static efficiency
6 M
1 (c)
Explain specific speed and specific power.
4 M
1 (d)
A model turbine 1 m in diameter acting under a head of 2 m runs at 150 RPM. Estimate the scale ratio if the prototype develops 20 MW under a head of 225 m with a specific speed Of 100.
6 M
2 (a)
Define polytropic efficiency of a compressor
4 M
2 (b)
What is reheat factor in a multi stage turbine? Prove that R.F is greater than unity
8 M
2 (c)
In a three stage turbine the pressure ratio of each stage is 2 and the stage efficiency is75%. Calculate the overall efficiency and reheat factor
8 M
3 (a)
Derive an alternate form of Euler's turbine equation and explain the significance of each energy components.
10 M
3 (b)
Al a 50% reaction stage axial flow turbine, the mean blade diameter is 0.60 meter. The maximum utilization factor is 0.85 and steam flow rate is 12 kg/s. Calculate the inlet and outlet absolute velocities and power developed if the speed is 2500 RPM
10 M
4 (a)
Derive an expression of theoretical head capacity relationship of radial outward flow devices(centrifugal machines).
10 M
4 (b)
An inward flow reaction turbine has outer and inner diameter wheel as 1 m and 0.5 m respectively. The vanes are radial at inlet and discharge is radial at outlet and fluid enters the vanes at an angle of 10°. Assuming the velocity of flow to be constant and equal to 3 m/sec. Find: i) Speed of wheel, ii) Vane angle at outlet, iii) Degree of reaction
10 M
5 (a)
What is compounding or staging? Name the different compounding method
4 M
5 (b)
The data pertaining to an impulse turbine is as follows:
Steam velocity : 500 m/sec, blade speed : 200 m/sec, exit angle at moving blade : 25° measured from tangential direction, nozzle angle : 20° Neglecting the effect of friction when passing through blade passages. Calculate:
1)Inlet angle of moving blade
ii) Exit velocity and direction
iii) Work done per kg of steam
iv) Power developed
v) Diagram deficiency.
Steam velocity : 500 m/sec, blade speed : 200 m/sec, exit angle at moving blade : 25° measured from tangential direction, nozzle angle : 20° Neglecting the effect of friction when passing through blade passages. Calculate:
1)Inlet angle of moving blade
ii) Exit velocity and direction
iii) Work done per kg of steam
iv) Power developed
v) Diagram deficiency.
16 M
6 (a)
Obtain an expression for the work done per second by water on the runner a pelton Wheel and Hydraulic efficiency.
10 M
6 (b)
A kapaln turbine has an outer diameter of 8 m and inner diameter as 3m and developing 30,000 KW at 80 RPM under a head of 12m. The discharged through the runner is 300 m2/sec. If the hydraulic efficiency is 95 % , determine:
i) Inlet and out let blade angles
ii) Mechanical efficiency
iii) Overall efficiency.
i) Inlet and out let blade angles
ii) Mechanical efficiency
iii) Overall efficiency.
10 M
7 (a)
Derive the expression for the minimum speed for starting a centrifugal pump
12 M
7 (b)
A centrifugal pump having outer diameter equal to two times inner diameter and running at 1200 RPM, words against a total head of 75m. The velocity of flow through the impeller is constant and equal to 3m/sec. The vanes are setback at an angle of 30° at outlet. If the outlet diameter of the impeller is 60cm and width at outlet is 5 cm. Determine:
i) Vane angle at inlet.
ii) work done per second by impeller.
iii) Manometric efficiency.
i) Vane angle at inlet.
ii) work done per second by impeller.
iii) Manometric efficiency.
8 M
8 (a)
Explain the phenomena of surging, stalling and chocking in centrifugal compressor stage
6 M
8 (b)
Draw velocity triangles at the entry and exit for the axial compressor stage.
6 M
8 (c)
An axial compressor/blower supplies air to furnace at the rate of 3 kg/sec. The atmospheric conditions being 100 kPa and 310 K. The blower efficiency is 80% and mechanical efficiency is 85%. The power supplied to 30 kW. Estimate the overall efficiency and pressure developed in mm WG
8 M
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