Hydrodynamic Lubrication Mechanism and CFD Analysis of Tesla-Valve Microtextures

Abstract

Titanium alloys are widely used in aerospace and medical industries owing to their high strength, low thermal conductivity and excellent corrosion resistance. However, their high chemical reactivity and poor heat dissipation cause severe tool wear during cutting. Surface microtexturing has been proven to significantly improve the lubrication performance of friction pairs and extend service life. To explore the lubrication mechanism of Tesla-valve microtextures, femtosecond laser machining was employed to fabricate micrometer-scale Tesla-valve structures on YG8N cemented carbide surfaces. A three-dimensional model was established in Fluent, and the velocity and pressure distributions at various inlet flow rates were simulated. The results show that at low speeds (v ≤ 2 m/s), the microtexture exhibits higher reverse than forward flow velocity, with superior reverse hydrodynamic lubrication performance; whereas at high speeds (v ≥ 3 m/s), the forward flow velocity exceeds the reverse, leading to improved forward hydrodynamic lubrication performance. As flow rate increases, the vortex region and pressure potential inside the microtexture expand significantly, enhancing the load-carrying capacity of the oil film.