An Experimental Investigation of the Steady-State Response of a Noncontacting Flexibly Mounted Rotor Mechanical Face Seal

Abstract

Recent theoretical work on the dynamics of the noncontacting flexibly mounted rotor (FMR) seal has shown that it is superior in every aspect of dynamic behavior compared to the flexibly mounted stator (FMS) seal. The FMR seal is inherently stable regardless of the operating speed, the maximum relative misalignment response is smaller, and the critical stator misalignment is larger. All these are measures of superior performance. This work undertakes the experimental investigation of the dynamic behavior of a noncontacting FMR seal. The steady-state response of the FMR seal was measured at various operating conditions. The results are given in terms of dynamic and static transmissibilities, i.e., amplitude ratio of responses to two forcing inputs: the initial rotor and fixed stator misalignments. These are then compared to the analytical predictions. Further, operation maps are drawn for each set of operation conditions. The maps indicate how safely (away from contact) the seal operates. It is shown that the combination of the seal parameters that maximize the fluid film stiffness is optimal for safe noncontacting operation.