Rotating body provided with blades

A rotating body comprising:

• a rotating body core;
• and
• a plurality of blades provided at an outer circumference or an inner circumference of the rotating body core at equal intervals in a circumferential direction, the plurality of blades forming a grouped blade structure in which the blades are connected over the entire circumference via an annular connection portion provided separately from the rotating body core, wherein
• a resonance frequency under a two nodal diameter number mode of the rotating body is higher than a rotational secondary harmonic frequency with respect to a rated rotation speed of the rotating body, and
• where an order of a maximum mistuned component is defined as Nd among order components of mass distribution, rigidity distribution, or natural frequency distribution of the plurality of blades in the circumferential direction, the plurality of blades are arranged so as to satisfy Nd≧6, and arranged so as to have order components each having a ratio less than 1/2, in which the ratio is obtained by dividing the order component by a magnitude of the component of the order Nd.

A method of manufacturing a rotating body which includes:

• a rotating body core;
• and a plurality of blades provided at an outer circumference or an inner circumference of the rotating body core at equal intervals in a circumferential direction, the plurality of blades forming a grouped blade structure in which the blades are connected over the entire circumference via an annular connection portion provided separately from the rotating body core, wherein a resonance frequency under a two nodal diameter number mode of the rotating body is lower than or equal to a rotational secondary harmonic frequency with respect to a rated rotation speed of the rotating body,
• the method comprising:
• where an order of a maximum mistuned component is defined as Nd among order components of mass distribution, rigidity distribution, or natural frequency distribution of the plurality of blades in the circumferential direction, arranging the plurality of blades so as to satisfy Nd≧5, and so as to have order components each having a ratio less than 1/2, in which the ratio is obtained by dividing the order component by a magnitude of the component of the order Nd.

A method of manufacturing a rotating body which includes:

• a rotating body core;
• and a plurality of blades provided at an outer circumference or an inner circumference of the rotating body core at equal intervals in a circumferential direction, the plurality of blades forming a grouped blade structure in which the blades are connected over the entire circumference via an annular connection portion provided separately from the rotating body core, wherein a resonance frequency under a two nodal diameter number mode of the rotating body is higher than a rotational secondary harmonic frequency with respect to a rated rotation speed of the rotating body,
• the method comprising:
• where an order of a maximum mistuned component is defined as Nd among order components of mass distribution, rigidity distribution, or natural frequency distribution of the plurality of blades in the circumferential direction, arranging the plurality of blades so as to satisfy Nd≧6, and so as to have order components each having a ratio less than 1/2, in which the ratio is obtained by dividing the order component by a magnitude of the component of the order Nd.