Variable stator vane structure of axial compressor

1. A variable stator vane structure of an axial compressor, comprising:

a cylindrical inner peripheral member;

a cylindrical outer peripheral portion coaxially disposed with respect to the cylindrical inner peripheral member so as to define an annular fluid passage in cooperation with the cylindrical inner peripheral member; and

a row of stator vanes arranged circumferentially in the annular fluid passage;

wherein each stator vane is provided with a shaft rotatably supported by the cylindrical outer peripheral portion around an axial center line of the shaft, and a vane member supported by the shaft,

the axial center line of the shaft being tilted with respect to a radial line emanating radially from a center of the annular fluid passage in a circumferential direction and/or in an axial direction of the annular fluid passage,

the vane member comprises a root edge, a tip edge, a leading edge and a trailing edge, and is rotatably supported so as to be rotatable around the axial center line of the shaft between a rated angular position and a non-rated angular position, the rated angular position being associated with taking off and cruising operation modes, and the non-rated angular position being associated with idling and taxiing operation modes, and

the axial center line of the shaft is tilted in a plane orthogonal to an axial line of the annular fluid passage so that an end point of the root edge on a side of the leading edge is in contact with an inner circumferential surface of the cylindrical outer peripheral portion, and an end point of the root edge on a side of the trailing edge is in contact with the inner circumferential surface of the cylindrical outer peripheral portion in the non-rated angular position.

2. The variable stator vane structure according to claim 1 , wherein

the end point of the root edge on the side of the leading edge is spaced from an intersection point of the axial center line of the shaft with the inner circumferential surface of the cylindrical outer peripheral portion by a prescribed distance along the axial center line of the shaft so that the end point of the root edge on the side of the trailing edge is in contact with the inner circumferential surface of the cylindrical outer peripheral portion in the rated angular position.

3. The variable stator vane structure according to claim 1 ,

wherein the axial center line of the shaft is tilted so that the end point of the root edge on the side of the trailing edge is in contact with the inner circumferential surface of the cylindrical outer peripheral portion in the rated angular position.

4. The variable stator vane structure according to claim 1 , wherein the vane member having a chord length L at the root edge, and

the axial center line of the shaft is tilted so as to be orthogonal to a hypothetical plane defined by an intersection point of the axial center line of the shaft with the inner circumferential surface of the cylindrical outer peripheral portion, an intersection of an end point of a line segment having a length equal to the chord length and extending from the intersection point in a direction of the rated angular position with the inner circumferential surface of the cylindrical outer peripheral portion, and an intersection of an end point of a line segment having a length equal to the chord length and extending from the intersection point in a direction of the non-rated angular position with the inner circumferential surface of the cylindrical outer peripheral portion.

5. The variable stator vane structure according to claim 4 , wherein the root edge extends linearly in a chord direction.

6. The variable stator vane structure according to claim 1 , wherein the leading edge of the vane member is positioned adjacent to the axial center line of the shaft.

7. The variable stator vane structure according to claim 1 , wherein a part of the root edge located ahead of the axial center line is provided with a cutout so as not to interfere with the inner circumferential surface of the cylindrical outer peripheral portion.