A hydrodynamic seal uses a dynamic rotor with grooves that act as a pump and create an air film that the opposing sealing surface will ride on.
A hydrodynamic seal performs better than hydrostatic seals by providing greater film stiffness, lower leakage and lower lift off speeds.
Hydrodynamic seals have a variety of applications in multiple industries.
there are a large number of various groove designs that have been proposed and tested.
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