METHOD OF AND APPARATUS FOR ENLARGING SURGE MARGIN IN CENTRIFUGAL COMPRESSOR AND AXIAL FLOW CONPRESSOR

摘要

PURPOSE:To permit enlargement of the surge margin without reducing the maximum stage efficiency by arranging such that part of fluid on the high pressure side is introduced to an inducer tip portion of a vane wheel at an instant when the working point of the compressor reaches a point right before the surge point or in the neighborhood of a stall point. CONSTITUTION:When the working point of the compressor reaches a point right before the surge point or the neighborhood of a stall point, this is detected, and at the same time part of the high pressure fluid extracted from a high pressure section of the compressor is led through a duct 14 and an on-off valve 13 to a header section 13, and is injected as a high speed jet from jet ports 12a of an injection ring 12 into an inducer tip section 9c. In consequence, instable low speed fluid over a vane surface 8 is given energy to increase the insensity of turbulence, whereby the boundary layer is prevente from being peeled-off or re-attached. In this way, an effect of enlarging the surge margin is reliably obtained to permit stable operation.