Development of a modelling strategy for cyclic asymmetric problems using the SPH approach

The present work presents a modelling strategy for 3D simulations of local oil jet injection into a rotating annular cavity by means of implementing an intermittent inlet boundary for an angular sector. The intermittent injection is used in order to capture the effects of the circumferential asymmetry of the problem. The objective of this methodology is to enable fast and reliable simulation of the under-race lubrication of the bearings in a jet engine. The main goal is a more accurate prediction of the oil distribution in the different feed holes of the bearing support. Oil is supplied onto a rotating shaft via an oil jet at one circumferential location and subsequently transported in a rotating annular cavity to the oil feed holes, which are placed in the outer ring of the annular cavity. Due to the complexity of the geometry and flow phenomena, the numerical method chosen to discretize the governing Navier-Stokes-Equations will be the meshless Lagrangian Smoothed Particle Hydrodynamics (SPH) approach. The proposed methodology is applied for simulations at different oil volume flows and rotor speeds. A resolution study is performed to evaluate the trade-off between accuracy and computational cost. ... mehrThe model as well as the occurring physical phenomena are investigated. Finally, a comparison with the data from a 360° simulation is conducted. Target parameters are film thickness and mass flows.