Numerical Investigation of Deep Surface Texture Performance Using a Finite Element Solution of the 2D Navier–Stokes Equations

This study presents a numerical investigation of the hydrodynamic performance of textured surfaces under lubrication, emphasizing the influence of texture geometry and manufacturing defects. Rectangular and semi-elliptical textures are compared using a fully coupled finite element model based on the Navier–Stokes equations, which overcomes limitations of Reynolds-based approaches near texture edges with steep gradients. To isolate geometric effects and clarify texture influence, this work focuses on noncavitating conditions where lubricant film pressure remains above the vapor threshold. The analysis evaluates pressure distribution, load capacity, flow patterns, and shear stresses for textures with identical depth-to-length ratios across varying Reynolds numbers. Semi-elliptical textures exhibit superior performance, generating higher lift and more stable flow with reduced separation, though they induce greater drag. The study also examines manufacturing deviations that produce inclined sidewalls in rectangular textures. The results show that deep cavities may benefit from such deviations, whereas shallow cavities experience a reduction in load-carrying capacity and an increase in friction. However, shorter textures remain less sensitive to these geometric variations, making them more suitable for practical applications. These findings provide insights for designing textured surfaces that balance friction reduction and load support under varying operating conditions.