Bearing Calculation and Analysis Capabilities – AxSTREAM®
Rotor dynamics analysis would neither be complete nor reliable without accurate modeling of bearings. The AxSTREAM® Bearing module uses a finite difference method that allows calculating mechanical (including direct and cross-coupled stiffness and damping coefficients) and hydrodynamic (maximum fluid pressure, minimum film thickness, etc.) characteristics of the following:
- Rolling elements bearing – Deep groove, self-aligning, spherical roller, straight roller, tapered roller, and so on
- Gas foil bearing
- Cylindrical journal (hydrodynamic) bearing with and without pockets
- Fixed and tilting pad journal bearing
- Fixed and tilting pad thrust bearings
- Squeeze film dampers
Additionally, properties of liquid annular seals as well as cross-coupling coefficients can be calculated in AxSTREAM Bearing.
The embedded library of fluids allows users to use new or existing incompressible and compressible fluids throughout different projects while accounting for temperature-dependent properties and heat transfer with housing and journal.
Analysis & Post-Processing
Several analyses using Finite Difference Method (FDM) can be performed in this module:
- Steady state – Considers bearing state under loading in order to determine equilibrium position, pressure distribution, bearing clearance, eccentricity, stiffness and damping.
- Whirl stability – Considers the bearing behavior during its transient operation and allows drawing conclusions on the stability of instability of the design for the studied rotation speed.
- Map analysis – Performs several inverse analyses in order to calculate the evolution of the mechanical characteristics for a given series of rotation speeds.
These properties can then be exported to a printer-friendly report or the AxSTREAM® RotorDynamics software in order to automatically use the appropriate values during rotor dynamics analyses.
Additionally, pockets, misalignments, etc. can be considered for the different calculations.
Moreover, the lubricant flow rate is calculated along with the heat balance and temperature distributions.