Compressor taxonomy: is a centrifugal compressor an axial-flow compressor? Decide whether the statement “A centrifugal compressor is an axial-flow compressor” is correct or incorrect.

Introduction / Context:
Compressors are categorized by the direction of primary flow relative to the machine axis. Correct classification matters for predicting performance maps, surge behavior, and stage loading limits.

Given Data / Assumptions:

• Centrifugal compressors have radial outflow through an impeller.
• Axial compressors have flow predominantly parallel to the shaft axis through multiple blade rows.

Concept / Approach:
A centrifugal compressor accepts flow near the center and imparts tangential velocity, flinging the fluid radially outward; static pressure then increases in a diffuser. An axial-flow compressor compresses the fluid while it moves axially through alternating rows of rotating and stationary blades. The flow directions and stage architectures are fundamentally different.

Step-by-Step Solution:

Verification / Alternative check:
Standard turbomachinery texts depict velocity triangles: centrifugal has a large radial component at impeller exit, while axial maintains nearly axial absolute velocity through stages.

Why Other Options Are Wrong:

Conditional “correct” options attempt to blur definitions; even with vaneless diffusers or multishaft layouts, the primary flow direction in centrifugal stages remains radial, not axial.

Common Pitfalls:
Confusing “mixed-flow” compressors with pure axial or pure centrifugal designs.

Final Answer:

Incorrect