Tilting Pad Journal Bearing CFD Parametric Modeling for New Energy Transition Challenges

Abstract

Abstract The necessity of increasing the efficiency and reducing the carbon foot-print of machines is pushing centrifugal compressor bearings design to higher and higher peripheral speed and lower oil consumptions especially in the new energy transition fields, resulting in an increase in the bearing temperatures. Therefore, the bearing thermal management starts to play a major role in extending the machine operability and reducing the maintenance frequency. A full three-dimensional (3D) parametric conjugate heat transfer Computational Fluid Dynamic (CFD) model for Tilting Pad Journal Bearings (TPJBs) is introduced in this paper to address the temperature aspects of oil-film bearings. The parametric geometry of the model and the automatic mesh update, allow the equilibrium position search to be obtained without adopting any dynamic mesh algorithms. The tilting pad and rotating shaft equilibrium position is automatically calculated with a Newton-Raphson algorithm. The static performance of the TPJB is investigated for different journal diameters, bearing clearance, and operating conditions. The numerical results obtained are compared with experimental data from Compressor Mechanical Running Tests to demonstrate the reliability of the model presented. The 3D distributions of the oil pressure, velocity and temperature given by the CFD model, can be locally optimized to face the new energy transition challenges.