1) Steam enters the group of nozzles of the steam turbine at 12 bar and 2200C and leaves at 1.2 bar. Steam turbine develops 220 Kw with a definite steam consumption of 13.5 Kg/ Kw. Hr. If a diameter of nozzle at throat Is 7mm . Compute the number of nozzle.
2) Deduce the expression for critical pressure ratio in terms of index of expansion.
3) Describe the method of governing in steam turbine.
4) Describe different kinds of compounding in Turbine.
6) A 50% reaction turbine running at 400 rpm has exit angle of blades as 20° and velocity of steam relative to blade at the exit is 1.35 times mean speed of a blade. Steam flow rate is 8.33 kg/s and at particular stage specific volume is 1.38m3/kg. Compute, appropriate blade height, supposing the rotor mean diameter 12 times the blade height, and diagram work.
7) Blade angle of the single ring of the impulse turbine is 300m/s and nozzle angle is 200. The isentropic heat drop is 473kJ/kg and nozzle efficiency is 85%. Given the blade velocity coefficient is 0.7 and blades are symmetrical, sketch the velocity diagram and compute for a mass flow of 1 kg/s
i) axial thrust on balding
ii) steam consumption per BP hour if mechanical efficiency is 90%
iii) blade efficiency and stage efficiency.