Mechanical Department for Atlas Copco Energas GmbH in Cologne, Germany. He has been with them since 1984, first as Manager of the Development Design for expanders, and then in his present position. Dr. Leonard received a Dipl.-Ing. degree (Mechanical Engineering) from Karlsruhe University. He did research in high-speed journal bearings at the Mechanical Design Institute and earned his doctoral ...

Hydrodynamic journal bearings are essential components for industrial rotating machineries. Continuously growing specific power allows more compact and efficient machines to be obtained, by reducing the environmental footprint of production plants. The aim this work is provide a new design an innovative pad Tilting Pad Journal Bearings (TPJBs) with embedded cooling circuit, able limit oil film ...

Misalignment effects increase the risk of scratch or seizure failure for journal bearings-rotor system. To investigate performances misaligned bearings, a full-scale system test rig is designed and orbits are tested under different speeds. Then, THD lubrication model established to simulate misalignment conditions. The results show that system, center bearing closing coupling fixed around coupl...

Abstract Fluid film bearings are well suited for high-speed industrial machineries like turbine generators and marine propulsion systems. Several numerical methods employed to theoretically investigate the flow phenomenon performance parameters of journal bearings, operating under various conditions. This paper reviews Computational Dynamics (CFD) Fluid–Structure Interaction (FSI) techniques th...

To investigate the static characteristics of aerostatic journal bearings with porous bushing, flow model—in which compressibility lubricating gas is considered—is established based on Reynolds lubrication equation, Darcy equation for material, and continuity equation. With finite difference method, schemes non-uniform grids, relaxation virtual node numerical method governing equations compressi...

The following content refers to the thermal aspects of Gas Foil Bearing (GFB). GFBs are subgroup journal bearings, for which lubrication is provided by air, instead ‘traditional’ lubricants like oil, graces etc. Bearings offer specific features unachievable traditional bearings. GFB can operate with rotating speed up several dozens krpm in extreme temperature hundreds Celsius degrees. However d...

This work presents a technique that allows the calibration of mathematical models in rotating systems. The method is based on the application of a hybrid meta-heuristic search, which employs genetic algorithm and simulated annealing. The capabilities of the method are evaluated by means of experimental results obtained in the test-rig of Politecnico di Milano. The experimental set up consists o...