A New Damper Seal for Turbomachinery

Abstract

Abstract A new type of labyrinth seal for damping vibration and whirl in turbomachinery has been invented and tested at Texas A&M University (TAMU). Test results of the prototype, along with a conventional labyrinth seal, show that the new design has fifteen times more direct damping than the conventional bladed seal. The design also has a feature that blocks swirl of the working fluid, which is known to be destabilizing in machines with conventional seals. This paper shows how the new design is different from conventional bladed seals and honeycomb seals, describes the test apparatus and results, describes a theory which explains the test results, and explains how the seal can be much more effective than a bearing damper for reducing vibration in turbomachines with a compressible working fluid.