The effects of surface roughness on air-riding seals are investigated here using the Rayleigh pad as an example. Both incompressible and compressible flows are considered using both CFD analysis and analytical/numerical solutions of the Reynolds equation for various two-dimensional or three-dimensional roughness patterns on the stationary wall. A “unit-based” approach for incompressible flows has also been employed and is shown to be computationally much less expensive than the full-geometry solution. Results are presented showing the effect of surface roughness on the net lift force. The effects of varying the Reynolds number are demonstrated, as well as comparative results for static stiffness.
Issue Section:Technical Papers
Keywords:rough surfaces, external flows, seals (stoppers), computational fluid dynamics, compressible flow
Munson, J., 1992, “Development of a High Performance Compressor Discharge Seal,” 28th Joint Propulsion Conference, AIAA Paper 92-3714.
Advanced Seals for Engine Secondary Flow Path,”
J. Propul. Power,
Acheson, D. J., 1990, Elementary Fluid Dynamics, Oxford University Press, Oxford, UK.
Anderson, J. D., 1989, Hypersonic and High Temperature Gas Dynamics, McGraw-Hill, New York.
Dyson, A., 1978, “Hydrodynamic Lubrication of Rough Surfaces—A Review of Theoretical Work,” Surface Roughness Effects in Lubrication, D. Dowson, C. M. Taylor, M. Godet, and D. Berthe, eds., Mech. Eng. Publications Ltd. London, pp. 61–70.
Pressure and Shear Flow in a Rough Hydrodynamic Bearing, Flow Factor Calculation,”
ASME J. Tribol.,
Szeri, A. Z., ed., 1980, Tribology: Friction, Lubrication and Wear, McGraw-Hill, New York.
M. T. C., and
On the Numerical Modelling of High-Speed Hydrodynamic Gas Bearings,”
ASME J. Tribol.,
Massey, B. S., 1983, Mechanics of Fluids, Van Nostrand Reinhold, New York.
Fluent Inc., 1998, http:www.fluent.com.
Tannehill, J. C., Anderson, D. A., and Pletcher, P. H., 1997, Computational Fluid Mechanics & Heat Transfer, 2nd Ed., Taylor & Francis, London.
Burden, R. L., and Faires, J. D., 1993, Numerical Analysis, PWS-Kent Publishing, Boston.
Copyright © 2004