2010 年 38 巻 4 号 p. 240-247
In the present paper, a 3-dimensional numerical study of partial admission stages of a steam turbine is described. Three models : Q3-D model only on mean diameter, 3-D model without tip clearances and disk cavities, and 3-D model with tip clearances and disk cavities, are applied and their results are compared with experimental results of a single stage air turbine. The mechanism of loss generation in partial admission stages is discussed by comparison with full arc admission stages. Tip leakage flow plays more significant role in partial admission stages.