Radial compressor fault identification using dynamic measurement data

Abstract

The exploitation of different unsteady quantity measurements for identifying mechanical alterations on a radial compressor with a vaned diffuser is examined in this paper. Measurements of sound emission, casing vibration and unsteady inner wall pressure are performed. The mechanical alterations considered have been chosen in order to reproduce or simulate faults in the compressor. They include the insertion of an inlet obstruction, an obstruction in a diffuser passage, variation of impeller tip clearance, and impeller fouling. Processing these measurement data leads to the derivation of fault signatures which can be utilized for identifying them. The suitability of measuring each of the above physical quantities is discussed with respect to their sensitivity to particular faults. The dependence of the fault signatures on operating point is also examined. It's demonstrated that minor faults which do not affect compressor operation and are not detectable by performance monitoring, can possibly be detected by the proposed methodology.