Journal-Fixed Mass-Conserving Reynolds Formulation for Surface Textures on Rotating Journals

Water lubrication offers a cleaner alternative to oil in marine journal bearings, but its low viscosity produces thinner lubricant films and increases the risk of friction and wear. Appropriately designed surface textures can improve hydrodynamic performance. In water-lubricated bearings, the steel journal retains machined features far longer than the softer polymer bearing surface, making journal-mounted textures attractive. Most Reynolds-based studies, however, consider textures fixed to the stationary bearing, whereas journal-mounted textures rotate and introduce an additional time-dependent effect. Moving-mesh and moving-multigrid methods have been used to capture this motion. This study isolates the texture-motion contribution as an explicit source term in a journal-fixed frame and solves the mass-conserving p–θ formulation on a fixed finite-difference grid. For a long bearing with a single axial channel, the predictions agreed with CFD results to within 2%, whereas omitting the texture-motion term reversed the phase of the load response over the revolution. For a cavitating finite-length bearing with chevron textures, the formulation reproduced published pressure results and captured a local pressure-reformation peak that is absent when texture motion is neglected. For the same case, the journal-fixed formulation reduced the CPU time by 53.6% relative to a classical global-frame formulation on a fixed grid. The verification uses conventional lubricant properties at low eccentricity and an illustrative water-lubricated case shows that the same chevron texture increases the peak pressure at ε=0.30 but reduces it at ε=0.60.