A METHOD AND DEVICE FOR DETERMINING THE OCCURENCE OF ROTATING STALL IN A COMPRESSOR'S TURBINE BLADE II

摘要

A method and device for determining the occurrence of rotating stall in the turbine blade (3) of a compressor (1), in which the blade pass frequency of at least one compressor stage (2) and the associated vibration energy are monitored, the normal blade pass frequency being constituted by the operating speed of rotation of the compressor (1) multiplied by the number of turbine blades (3) in the stage (2), and in which incipient rotating stall in a compressor stage (2) is indicated when, at the normal blade pass frequency (34) of the compressor stage (2), the vibration energy (28) falls below a predetermined first value (40) at the same time as, at a blade pass frequency (42) above the normal blade pass frequency (34), the vibration energy (30) rises above a predetermined second value (44).