Seal Analysis & Design

Annular seals play a critical role in many machines’ efficiency and can significantly affect their vibrational performance.

For example:

  • Wear rings support a centrifugal pump’s rotor with vital stiffness and damping, dictating its critical speeds

  • Labyrinth seals in compressors or turbines can produce significant destabilizing effects, leading to violent sub-synchronous vibration due to rotor instability

The reliability of hydrogen cooled generators and process centrifugal compressors can also be heavily dependent on the leakage and dynamic performance of floating bushing oil seals.

BRG’s team of consultants examine annular seals’ performance using a variety of tools.

Specialized computer programs

  • Employ accepted industrial theories

  • Predict leakage, dynamic coefficients and power loss

  • Model typical industrial designs including

    • Pumps: smooth and grooved wear rings

    • Compressors/Turbines: labyrinth and hole pattern / honeycomb

  • Extensively validated and successfully used

Computational fluid dynamics (CFD)

  • Models complex geometries & multi-phase flow

  • Offers superior accuracy & physical insight

  • Helps detailed designs such as swirl brakes

Center bushing performance within a boiler feed pump

Validation of direct damping predictions for a hole pattern seal

Preswirl influences on labyrinth seals’ effective cross-coupled stiffness

Flow vectors within a hole pattern seal