Abstract
An analysis for turbulent grooved seals which are the most common design in commercial pumps was developed and tested to predict leakage and dynamic coefficients, as related to rotor- dynamics. The grooved surface roughness pattern is formulated as an inhomogeneous directivity in surface shear stresses. The governing equations are expanded in the eccentricity ratio to yield zeroth and first-order perturbation solutions. Comparisons between analysis and experimental data are carried out in terms of effective stiffness, effective damping, and effective inertia coefficients for both tapered and constant-clearance circumferentially-grooved seals. Agreement between test results and analysis for net-damping coefficients is satisfactory, but the stiffness predictions have mixed results. Test results for a range of circumferential-grooving patterns show superiority in leakage performance, but inferiority in net-damping coefficients, as compared to the smooth seal and damper seal.* Analytical results are presented for helically-grooved seals in the High Pressure Oxygen Turbopump (HPOTP) of the Space Shuttle Main Engine (SSME) to determine the influence of seal parameters on dynamic coefficients, stability estimates, leakage performance, and power consumption. The proper selection of seal parameters improves the seal performance in terms of leakage and stability.
Kim, Chang-Ho (1985). Analysis and testing for rotordynamic coefficients of grooved turbulent annular seals. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -595960.