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Theoretical approach to obtaining dynamic characteristics of noncontacting spiral-grooved sealsThe dynamic characteristics of spiral-grooved seals are theoretically obtained by using the Navier-Stokes equation. First, with the inertia term of the fluid considered, the flow and pressure in the steady state are obtained for the directions parallel to and perpendicular to the groove. Next, the dynamic character is obtained by analyzing the steady state and by analyzing the labyrinth seal. As a result, the following conclusions were drawn: (1) As the land width becomes shorter or the helix angle decreases, the cross-coupling stiffness, direct and cross-coupling damping, and add mass coefficients decrease; (2) As the axial Reynolds number increases, the stiffness and damping coefficients increase. But the add mass coefficient is not influenced by the axial Reynolds number; (3) The rotational Reynolds number influences greatly the direct and cross-coupling stiffness and direct damping coefficients; and (4) As the journal rotating frequency increases, the leakage flow decreases. Therefore zero net leakage flow is possible at a particular rotating frequency.
Document ID
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Iwatsubo, Takuzo
(Kobe Univ. Japan)
Yang, Bo-Suk
(Kobe Univ. Japan)
Ibaraki, Ryuji
(Toyota Motor Co. Tokyo, Japan)
Date Acquired
September 5, 2013
Publication Date
January 1, 1987
Publication Information
Publication: NASA. Lewis Research Center Rotordynamic Instability Problems in High-Performance Turbomachinery, 1986
Subject Category
Mechanical Engineering
Accession Number
Distribution Limits
Work of the US Gov. Public Use Permitted.
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