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Experiment of static and dynamic characteristics of spiral grooved sealsThe leakages and the dynamic characteristics of six types of spiral grooved seals are experimentally investigated. The effect of the helix angle of the seal is investigated mainly under the condition of the same nominal clearances, land and groove lengths, and groove depths. The dynamic characteristics are measured for various parameters such as preswirl velocity, pressure difference between inlet and outlet of the seal, whirling amplitude, whirling speed, and rotating speed of the rotor. The results are also compared with leakage increases with the increase of the helix angle, but as the rotating speed increases, the leakages of the larger helix angle seals quickly drop. The leakage of the smooth-stator (SS)/smooth-grooved rotor (SGR) seal drops faster than that of the spiral-grooved stator (SGS)/smooth-rotor (SR) seal. It is found that a circumferential flow can be produced by the flow along the helix angle direction, and this circumferential flow acts as a negative swirl. For the present helix angle range, there is an optimum helix angle with which the seal has a comparatively positive effect on the rotor stability. Compared with the SGS/SR seals, the SS/SGR seal has a worse effect on the rotor stability.
Document ID
19920005143
Document Type
Conference Paper
Authors
Iwatsubo, T.
(Kobe Univ.)
Sheng, B. C.
(Kobe Univ.)
Ono, M.
(Kobe Univ.)
Date Acquired
September 6, 2013
Publication Date
October 1, 1991
Publication Information
Publication: NASA. Lewis Research Center, Rotordynamic Instability Problems in High-Performance Turbomachinery, 1990
Subject Category
Mechanical Engineering
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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