Paper: Profile optimisation of hydraulic, polymeric, sliding seals by minimizing an objective function of leakage, friction and abrasive wear.

Author: George K. Nikas

Published in: Lubricants, 2020, 8(4), article 40 (open access)


Hydraulic dynamic seals for reciprocating or alternating motion are machine elements with widespread applications in the automotive, aerospace, marine, pharmaceutical and several other industrial sectors. They have been under commercial development for many decades and are often met in critical positions, consuming a considerable amount of energy during operation. An objective function of mass leakage rate, friction force and an abrasive-wear representative term is proposed in the present study to evaluate the performance of hydraulic, polymeric, sliding seals under suitable constraints. Using Variational Calculus, analytical and numerical techniques, the objective function is minimized, resulting in an optimal seal profile that maximizes sealing performance for given, steady-state operating conditions, in additional consideration of the structural integrity and manufacturability of the modified seal. The obtained seal shape and related pressure distribution are reminiscent of those for U-cup and step seals, designs which dominate the industry. In the course of the mathematical analysis, some major obstacles are documented, which show how sensitive and complicated sealing performance really is.


Graphical abstract

Graphical abstract

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