Which of the following is a disadvantage of a Curtis Stage?

A Curtis Stage, which is a type of steam turbine design, is known for its specific advantages, such as compactness and the ability to achieve high speeds. However, it does come with some trade-offs that can affect overall performance.

The option indicating poor efficiency as a disadvantage is correct because, while Curtis stages can be efficient in transforming energy, they typically experience losses due to factors such as friction and turbulence within the rotor and the flow path. These inefficiencies manifest especially under varying loading conditions or when operating outside their intended design parameters. The design focuses on enabling high-speed operation, but this can compromise efficiency compared to other turbine designs that prioritize smooth flow and lower friction losses.

In contrast, a large pressure drop or a large temperature drop may not necessarily represent a disadvantage in a Curtis Stage. These features can sometimes be a result of the operational parameters and design objectives of the turbine. Similarly, a reduced length of the rotor can be an advantage in favor of space and construction concerns, depending on the application requirements and constraints. Therefore, while these factors can pose challenges, they are not as inherently linked to the efficiency of the turbine as the designation of poor efficiency is.