Performance study of Tesla valve-type grooved face self-pumping hydrodynamic mechanical seals

To address the limitation of low stiffness in diffuser-type self-pumping hydrodynamic mechanical seals, a novel Tesla valve–type grooved self-pumping hydrodynamic mechanical seal structure is proposed, which leverages the unidirectional conduction characteristic of the Tesla valve to achieve a localized high-pressure accumulation effect.A geometric and mathematical model of the Tesla valve groove structure was established, and numerical simulations were conducted using Fluent to evaluate the sealing performance under various operating and structural parameters. A comparative analysis was performed between the diffuser-type and Tesla valve–type grooved self-pumping hydrodynamic mechanical seals, aiming to investigate the influence of both operating conditions and structural design variables on sealing performance.The results indicate that, compared to the diffuser-type self-pumping hydrodynamic mechanical seal, the Tesla valve–type grooved configuration achieves a 1%–3% reduction in leakage rate and a 25%–57% increase in fluid-film stiffness. Both stiffness and leakage rate exhibit growth with increasing medium pressure and rotational speed. Leakage rate remains relatively stable with increasing divergence angle and valve spacing, while at high rotational speeds, it increases with greater groove depth and groove width. Additionally, both leakage rate and stiffness show a non-monotonic trend with respect to the number of grooves—initially increasing and then decreasing. Fluid-film stiffness increases with larger divergence angles and groove widths, but decreases as valve spacing increases. With increasing groove depth, stiffness first declines, then recovers, and ultimately stabilizes.Under appropriate operating conditions, the Tesla valve–type grooved self-pumping hydrodynamic mechanical seal can achieve superior sealing performance through optimal structural parameter matching.