| In order to physically explain how the combined effect of turbulence and curvature affect the flow field in an annular and labyrinth seal, the present work presents measurements of the dynamic and mean pressure distributions on the stator wall of whirling annular and labyrinth seals for three different pre-swirl conditions: --45, 0 and +45 degrees. A calculation of the forces and moments generated by the pressure field has been performed and an analysis of the effect of swirl on the pressure field developed. In addition, because of the complex three dimensional nature of the flow and curvature which is not in the streamline direction, any prediction of the flow should be based on experimental boundary conditions to seek a convergence of the equations with better agreement with reality. Such predictive ability would greatly aid in the design of labyrinth and annular seals which are critical turbomachinery components. By providing these dynamic and mean pressure boundary conditions and utilizing the flow field velocity measured by Morrison et al. (1990, 1994), it is hoped that the following work will be a step toward improving simulation and therefore reduce testing and development cost. To illustrate the use of these data, computer simulations of centered and 50% eccentric annular and labyrinth seals for the different preswirls were performed using a CFD code, FLUENT UNS. These computer simulations of pressure and velocity data were compared to the pressure and LDV measurements. |
