Abstract
Stall stagnation phenomena in the system of axial-flow compressors and ducts are studied on the basis of analytical
results by a code on surge transients analysis and simulation with respect to a variety of delivery duct configurations coupled with either a nine-stage compressor or a single stage fan. The stall stagnation boundary was found to be formed mainly
by two zones, B- and A-boundaries. The B-boundary occurs for short and fat plenum-type delivery ducts. It is related with
some limiting conditions of E.M. Greitzer's B parameter. The A-boundary, a newly-found one, occurs for narrow and long
delivery ducts in the case of the suction duct with relatively short length. The boundary duct lengths are found to be compact
compared with the wavelength of the fundamental resonance frequency of the system. More detailed features of the
stagnation boundaries and the related flow behaviors will be presented in the next reports of this study.
