| 摘要 |
PROBLEM TO BE SOLVED: To improve acceleration responsiveness of a turbine impeller 15 while suppressing degradation of turbine efficiency.SOLUTION: A radius R1 of a maximum diameter face 17g of a turbine disk 17 is determined to be shorter than a radius of rotation R2 of a front edge 19a of a turbine blade 19; an axial position of a hub end 19ah of a front edge 19a of the turbine blade 19 is positioned at a front side with respect to an axial position of a boundary portion BD of the maximum diameter face 17g of the turbine disk 17, and a basic end edge 19b of the turbine blade 19; an annular fitting space AS is defined and formed by a rotational locus of a part 19be positioned at a radial outer side with respect to the boundary portion BD, of the basic end edge 19b of the turbine blade 19 and the maximum diameter face 17g of the turbine disk 17; and a fitting projection 27p of a heat shielding plate 27 is fitted to the fitting space AS. |
