Numerical Modeling of Fluid’s Aeration: Analysis of the Power ‎Losses and Lubricant Distribution in Gearboxes

Document Type : Research Paper

Authors

Faculty of Science and Technology, Free University of Bolzano, Piazza Università 1, Bolzano (BZ), 39100, Italy

Abstract

Aeration determines the entrainment of air in another fluid. In geared transmissions, this process affects the operating temperature of the mechanical system because the air’s bubbles trapped in the lubricant act as an insulator. Lubricant’s aeration occurs mainly because the gears’ teeth entering the oil sump and the oil impacting on free surface. Being able to numerically model aeration is fundamental to better describe the physics and the lubrication mechanisms which affect the behavior of the system. In this paper, a new solver that includes the aeration phenomenon was implemented in the opensource environment OpenFOAM®. The simulations’ results were validated with torque measurements. Moreover, a comparison of the oil distribution between a standard multiphase- and the new aeration-solver is provided.

Keywords

Main Subjects

Publisher’s Note Shahid Chamran University of Ahvaz remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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