Question 678Steam Plants - Assistant Engineer

The correct answer is A) Diaphragm packing loss. In a multi-stage impulse turbine, the steam flows through a series of stationary nozzles and moving blades. The diaphragms separating the turbine stages have packing seals to minimize steam leakage between stages, which results in diaphragm packing loss. This type of loss is more associated with impulse turbines rather than reaction turbines, where the steam pressure drop occurs primarily across the stationary blades. The other options, B) Blade and nozzle loss, C) Radiation loss, and D) Leaving loss, are general steam turbine losses that can occur in both impulse and reaction turbine designs.