Which statement correctly identifies the two basic compressor types?

Which statement correctly identifies the two basic compressor types?

• A. Axial-flow and centrifugal-flow.
• B. Radial-flow and axial-flow.
• C. Axial-flow and mixed-flow.
• D. Centrifugal-flow and radial-flow.

Answer: (A)

Compressors in gas turbine engines are categorized by how the air actually flows through them. The two basic types are axial-flow and centrifugal-flow. In an axial-flow compressor, air moves parallel to the engine axis and passes through multiple stages of rotor and stator blades, so the pressure rises gradually as the air advances through many stages. This arrangement supports very high flow and high overall pressure ratios, which is why it’s used in large, high-performance engines. In a centrifugal-flow compressor (also called a radial-flow compressor), air enters near the center and is flung outward by a spinning impeller, gaining energy and then being diffused to convert that energy into pressure. This design is simpler and robust, delivering a strong pressure rise per stage but typically at lower total flow and with more weight for the same pressure rise, so it’s common in smaller engines or as a booster stage in some systems. Thus, axial-flow and centrifugal-flow represent the two fundamental paths air can take to be compressed in gas turbine systems. (Radial-flow is another term often used for centrifugal, so you’ll see that wording in some texts, but the standard two basic categories are axial-flow and centrifugal-flow.)

Compressors in gas turbine engines are categorized by how the air actually flows through them. The two basic types are axial-flow and centrifugal-flow. In an axial-flow compressor, air moves parallel to the engine axis and passes through multiple stages of rotor and stator blades, so the pressure rises gradually as the air advances through many stages. This arrangement supports very high flow and high overall pressure ratios, which is why it’s used in large, high-performance engines.

In a centrifugal-flow compressor (also called a radial-flow compressor), air enters near the center and is flung outward by a spinning impeller, gaining energy and then being diffused to convert that energy into pressure. This design is simpler and robust, delivering a strong pressure rise per stage but typically at lower total flow and with more weight for the same pressure rise, so it’s common in smaller engines or as a booster stage in some systems.

Thus, axial-flow and centrifugal-flow represent the two fundamental paths air can take to be compressed in gas turbine systems. (Radial-flow is another term often used for centrifugal, so you’ll see that wording in some texts, but the standard two basic categories are axial-flow and centrifugal-flow.)