Abstract
A single stage ultra micro centrifugal compressor constituting ultra micro gas turbine is required to operate at high rotational
speed in order to achieve the pressure ratio which establishes the gas turbine cycle. As a consequence, the relative
Mach number of the flow in the impeller passage increases and then the shock wave which causes the loss by the interaction
with the boundary layer on the blade surface can be induced. In addition, the restriction of processing technology for the
downsizing of impeller not only relatively enlarges the size of tip clearance but also makes it difficult to process the
impeller with the three-dimensional blade. Therefore, it is important to establish the design technology for the impeller with
two-dimensional blade which possesses the sufficient aerodynamic performance and enough strength to bear the centrifugal
force caused by the high rotational speed.
In this study, the flow in two types of impeller with the two-dimensional blade which have different meridional configuration
was analyzed numerically. The computed results clarified the effects of the meridional configuration on the loss generation
in the impeller passage.
