The geometry of a two stage velocity compounded impulse steam turbine is as shown in Figure Q4. The following design conditions apply:- All angles are measured from the axial flow

direction (+ve = anticlockwise) The nozzles in the 1st stage are fed with steam at 30 m/s at 10 bar, 250°C.The fixed nozzles have an exit angle of -70° and expand the steam to2.5 bar, saturated vapour. Steam passes through the 1st stage moving blades and exits at +60°. Steam passes through the 2nd stage fixed blades and exits at -70°. Steam leaves the 2nd stage axially (with zero whirl) The mean diameter of the moving blades in both stages is 0.80 m. The rotor is required to rotate at 3000 rev/min. The fixed and moving blade entry angles are designed for smooth, shock freentry The blade velocity coefficient for all fixed and moving blades is 0.90. a) Sketch the velocity diagrams for the 1st and 2nd stages Determine:- b) The steam velocity at the exit from the fixed nozzles.[3 r c) The optimum entry angles of the 1st stage moving blade and the 2nd stage fixed blades[6 marks] d) The optimum exit angle of the 2nd stage moving blades [ e) The total power output per kg/s of steam in the 2 stages f) Comment briefly on the effect of raising the steam pressure at the inlet to the fixed nozzles.[4 marks]