Rotordynamics and Air Lubrication

Aerodynamic foil bearings allow oil-free bearing of high-speed rotors and are designed for operation at high or low temperatures. The elastic foil structure in foil bearings ensures that thermal and mechanical deformations (e.g. expansion due to centrifugal forces) during operation and manufacturing inaccuracies can be compensated for, so that lubrication in the bearing is ensured without breakage despite higher eccentricity of the rotor. The effective structural damping mechanism in foils increases energy dissipation throughout the bearing, and with optimal design, self-excited vibration can be avoided over the entire speed range. The high-precision design and dimensioning of air bearings for different operating conditions is a demanding task. We will be pleased to support you with competent advice in the field of film and air bearings for rotating machine parts. Whether designing new concepts or applying oil-free bearings with our software and hardware competences – SADAP is there for you.

Our services in the field of rotor bearing systems as PDF

Experimental Studies

Experimental studies (out of operation):

The foil bearing consists primarily of compliant foil structures connected in series with the lubrication film to provide stiffness and damping. This additional viscoelastic property keeps the bearing more robust to harmonic and subharmonic shocks and protects the minimum lubrication film thickness from failure.

Based on this consideration, the dynamic properties of the foil structure as a function of the excitation frequency play an essential role. In this respect, SADAP offers a careful investigation of the dynamic behavior of the foil bearings with a focus on film structure and out of service. This type of investigation is called measurement of the mechanical impedance of the foil structure.

The bearing assumed for investigation is harmonically excited in two directions perpendicular to each other (up to 9000 Hz) and the deflection in the respective directions is measured. Post-processing of the measured data determines how the stiffness and damping coefficients of the foil structure react to different frequencies that may occur during operation.

Training offers

Benefit from high-quality knowledge in the direction of optimizing your company’s performance.

  • Are you looking for a high-performance training partner?
  • Want to train your team at a specific location?
  • Or are you planning to have development staff on your team trained in specific areas of expertise?

SADAP is here for you!

We offer training services for industrial workers with unique knowledge potential in all areas covered by SADAP. These are mainly training services in the field of rotor dynamics calculation, bearing testing and evaluation of data from experimental investigations and simulation products. But that is not all we would like to offer you. You are welcome to send us your individual request as a corporate customer in the following areas:

  • Structural Health Monitoring area
  • System identification under mechanical aspects
  • Adaptive electromechanical solutions for vibration and noise reduction