Early Detection Of Rotating Stall Phenomenon In Centrifugal Compressors By Means Of ASME PTC 10 Type 2 Test

Abstract

A centrifugal compressor presenting rotating stall can exhibit many problems, as limitation on its operational range, high level of subsynchronous vibrations, reduced efficiency and premature bearing wear. There are many design criteria and standard practices for aerodynamic design of impellers and diffusers of centrifugal compressors. Nonetheless, the inception of rotating stall in new projects is still a reality. Therefore, an early detection of this phenomenon in a compressor is highly desirable. This paper proposes a way to detect the rotating stall problem during an ASME PTC10 Type 2 Test and how to scale these results (amplitude of vibration and inception point) as an estimative to site conditions. A comparison between the results of the proposed extrapolation from ASME PTC10 Type 2 Tests to the full load/density (almost an ASME PTC-10 Type 1 test) conditions is also presented. Scaling up guidelines for vibrations from similarity test to full density conditions are presented. Finally, an acceptance criterion for the amplitude of subsynchronous vibrations is proposed.