🔍 Key Concepts

• Axial and centrifugal compressor rotor dynamics • How bearing condition affects rotor alignment and radial clearance • Difference between gradual dimensional changes vs sudden mechanical failures

💭 Think About

• Which option would suddenly change the rotor position so the blade tips move closer to the case? • Which options would mainly change the shape or surface of the blades or casing without shifting the whole rotor? • After break‑in, what part is most likely to lose support or alignment and let the rotor move off‑center?

✅ Before You Answer

• Identify which choice directly affects rotor support and alignment rather than blade geometry alone • Think about what would most quickly reduce radial clearance between blade tips and casing • Eliminate options that only involve surface treatment or minor dimensional change without moving the rotor axis