This paper details an experimental study of the performance of a two laminate layers, single padded finger seal proposed by Proctor and Steinetz, and represents the natural development of a research effort pursued by Braun et al. Until now, these efforts materialized into modeling and numerical simulations of the structural and thermofluid behavior of this type of seal. For the finger seal, the compliance, combined with the non-contacting characteristic (not available with a brush seal) allows both axial and radial adjustment of the seal to the rotor excursions, without losing physical integrity, or sealing capability. In this experimental study the authors prove the conclusions of their numerical studies and design, that is, the pads of the low-pressure laminate exhibit enough lifting capability to allow the entire seal to lift, float over the surface of the shaft and provide non-contacting sealing capability at the same time. The finger seal lifting properties and its structure compliance are evaluated through the performance of a set of parametric studies where the seal's upstream pressure and the rotor angular velocity are gradually increased to 138 kPa (20 psid) and 14 krpm respectively, separately, or in conjunction with each other. Throughout this set of experiments, the leakage flow and the temperature of the pads are continuously monitored. The study concludes that the finger seal design tested in these experiments has successfully proven its non-contacting sealing capabilities during operation.
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