Abstract: Rotor structure for a turbomachine, such as a centrifugal compressor, is provided. Disclosed embodiments make use of structural and/or operational relationships (e.g., distinct axially-extending zones in the radially-inner contour of respective impeller bodies configured to balance mass distribution about a rotor axis) designed to control relative radial and/or axial growth between corresponding interface locations along the rotor axis at which corresponding faces of respective hirth couplings mesh with one another. The ability to control relative radial and/or axial growth between corresponding interface locations may be effective for reducing rotor vibration and/or to establish more reliable contact patterns and reduced levels of mechanical stresses and distortion (e.g., angular distortion) at the hirth coupling interfaces.

Abstract: Rotor structure for a turbomachine, such as a centrifugal compressor, is provided. Disclosed embodiments make use of structural and/or operational relationships (e.g., distinct axially-extending zones in the radially-inner contour of respective impeller bodies configured to balance mass distribution about a rotor axis) designed to control relative radial and/or axial growth between corresponding interface locations along the rotor axis at which corresponding faces of respective hirth couplings mesh with one another. The ability to control relative radial and/or axial growth between corresponding interface locations may be effective for reducing rotor vibration and/or to establish more reliable contact patterns and reduced levels of mechanical stresses and distortion (e.g., angular distortion) at the hirth coupling interfaces.