In: Mechanical Engineering
Steam enters the nozzle of an impulse turbine stage at 60 bar and 500 °C and leaves at 20 bar. Flow is adiabatic and reversible. The nozzle angle is 20°. The moving blade is symmetric, travels at optimum velocity, and assumed to be frictionless. It is also assumed that there is neither expansion nor contraction of the steam flow through the blade passage. Draw the velocity diagram and calculate (a) the blade efficiency and (b) the stage efficiency.