Squeeze Film Dampers: Effect of Central Groove on identified force coefficients
MAJOR APPLICATION: Attenuate vibrations and isolate the rotating components from the engine structure
Sponsors: Pratt & Whitney Engines,
Objective: To assess the forced dynamic performance of two parallel SFDs for various geometries and end conditions, and to develop a SFD predictive code benchmarked against test data
Status: A SFD test rig is designed to sponsor specifications, manufactured and assembled in the laboratory. The test rig is highly modular in construction – the geometry, squirrel cage support stiffness, lubricant supply arrangement and end conditions can be quickly reconfigured. A static loader enables SFD operation on static off-centered positions. Electromagnetic shakers (500 lbf) deliver dynamic excitations to the test structure along two orthogonal directions. A data acquisition and control code controls the shakers and acquires data from a multiple sensors.
Test rig is assembled and fully operational. Frequency domain parameter identification procedures are developed. SFD added mass (inertia) and damping coefficients are identified for two SFD land lengths, multiple support stiffnesses and active lubricant feeding holes, lubricant flow rates and groove pressures, and open and sealed end conditions. A computational FORTRAN® code using a finite element formulation of the Reynolds equation is developed. The predictions of SFD added mass and damping coefficients are benchmarked against experimental coefficients
TEST RIG STRUCTURE
Updated Jan 21, 2011