Exploring the potential of CFD in gear jet lubrication design: a systematic literature review

Abstract Gear jet lubrication, while notably efficient, poses substantial challenges for reliable analysis and design due to its inherent complexity. Over recent decades, Computational Fluid Dynamics (CFD) has become an indispensable tool, enabling detailed qualitative and quantitative evaluations to improve gear lubrication system designs. CFD applications extend to predicting impingement patterns, simulating oil distribution behavior, analyzing lubricant flow in the meshing zone, estimating heat dissipation, and assessing load-independent power losses, such as churning, squeezing, and windage. Research spans a variety of gear systems, from a single spur gear to complex assemblies like planetary and spiral bevel gearboxes. Diverse mesh-handling techniques, including Local Remeshing, Global remeshing, Overset Grid, Rotating Reference Frame, Sliding Mesh, and mesh-free methods such as Smoothed Particle Hydrodynamics (SPH), have been effectively applied. The literature covers both compressible and incompressible fluid models, along with isothermal and Conjugate Heat Transfer (CHT) analyses. Various turbulence models, such as k‑ω and k‑ε, are also employed. Numerous studies include experimental validation, confirming the credibility of CFD results. The scope of this work is to compile and organize existing CFD studies on gear jet lubrication, highlighting the commonalities and differences in methodologies found in the scientific literature. It provides a comprehensive, critical review of the current state-of-the-art in the field.