Multi-Scale Modelling of Oil Lubricated Contacts in Machine Elements

In this study, the numerical modelling of the Thermo-Elasto-Hydrodynamic Lubrication (TEHL) contact is investigated. Flow model, structure, and lubricant rheology models have been developed in the OpenFOAM (extend version) package. Regarding complex and cavitating flow in TEHL contact, a Homogeneous Equilibrium Model (HEM) is used, including the thermal effect and variation in lubricant properties due to pressure, temperature, and shear rate. Also, the Molecular Dynamic (MD) can be employed to calculate the density and viscosity as a function of state variables and shear rate. Besides the linear elastic equation, the heat conduction equation is solved to describe the solid deformation and temperature distribution in the solid domain. Furthermore, a partitioned Fluid-structure interaction (FSI) methodology is employed to make a two-way coupling between fluid and solid regions. Also, along with FSI modelling, a Conjugate Heat Transfer (CHT) simulation is essential to precisely investigate the thermal behaviour of TEHL contacts. The developed TEHL model properly shows the involved physics in comparison with acceptable data for rolling-sliding 2D line contacts from the literature and provides trustworthy results in different operating conditions for 2D/3D smooth and rough contacts.