2 TMA401M OCT/NOV 2015 QUESTION-1 [20 Marks] A multi-stage high-pressure steam turbine is supplied with steam at a stagnation pressure of 50 bar and a stagnation temperature of 500 °C The Corresponding specific enthalpy is 3440 kJ/kg. The steam exhausts from the turbine at a stagnation pressure of 5 bar absolute, the steam having been in a superheated condition throughout the expansion It can be assumed that the steam behaves like a perfect gas over the range of the expansion and that the y = 13 Given that the turbine flow process has a small- stage efficiency of 0 8, determine (1) The temperature and specific volume at the end of the expansion, (11) The reheat factor The specific volume of superheated steam is represented by pv = 0 231(h-1943) Where "p" is in kPa, "V" is in m³/kg and "h" is in kJ/kg [10] [10] QUESTION-2 [20 Marks] QUESTION-3 [20 Marks] An axial-flow turbine operating with an overall stagnation pressure ratio of eight has a poly-tropic efficiency of 0 85 (1) Determine the total-to-total efficiency of the turbine [8] (1) If the exhaust Mach number of the turbine is 03, determine the total-to-static efficiency [6] ) If, in addition, the exhaust velocity of the turbine is 160 m/s, determine the inlet total emperature ssume for the gas that Cp = 1 175 kJ/(kg K) and R = 0 287 kJ/(kg K) [6]