Shroud, blade member, and rotary machine
A shroud ( 22 ) comprises shroud bodies ( 22 ) fixed to blade tips of blades ( 18 ) mounted to a rotor body to extend in a radial direction, the shroud bodies ( 22 ) being disposed adjacent to one another in a circumferential direction, wherein each of the shroud bodies ( 22 ) includes a circumferential end surface ( 27, 28 ) that includes an abutting end surface where adjacent shroud bodies ( 22 ) abut, and an opposing surface ( 34 ) where adjacent shroud bodies ( 22 ) face one another with a clearance ( 32 ) therebetween, the opposing surface ( 34 ) being contiguous with the abutting end surface; and an outer surface ( 24 ) that includes a radially outward protruding protrusion ( 40 ) formed to extend along the opposing surface ( 34 ).
1. A shroud comprising:
shroud bodies fixed to blade tips of blades mounted to a rotor body to extend in a radial direction, the shroud bodies being disposed adjacent to one another in a circumferential direction, wherein
each of the shroud bodies includes:
a first circumferential end surface which is formed on one side in the circumferential direction, and which is formed on a leading side in a rotational direction of the blades;
a second circumferential end surface which is formed on the other side in the circumferential direction, and which is formed on a trailing side in the rotational direction of the blades; and
an outer surface which is a surface facing radially outward,
the first circumferential end surface and the second circumferential end surface include:
first opposing surfaces which are adjacent shroud bodies which face one another, and which are opposing surfaces intermediated by a first clearance on an upstream side of the shroud;
second opposing surfaces which are adjacent shroud bodies which face one another, and which are opposing surfaces intermediated by a second clearance on a downstream side of the shroud; and
abutting end surfaces which are adjacent shroud bodies which abut one another, and disposed between the first opposing surfaces and the second opposing surfaces,
in the first circumferential end surface and the second circumferential end surface, the first opposing surfaces, the abutting end surfaces and the second opposing surfaces are arranged in order from the upstream to the downstream of the shroud, and
the outer surface is provided with a protrusion projecting radially outward and formed so that it extends along the second opposing surface of only the first circumferential end surface and in a direction intersecting the rotational direction of the rotor body, so as to reduce the amount of combustion gas leaking through the second clearance between the adjacent shroud bodies.
2. The shroud according to claim 1 , wherein
the second clearance has a distance between the second opposing surfaces that is greater at a side approximate to the abutting end surfaces; and
the protrusion protrudes from the outer surface to a greater degree at the side approximate to the abutting end surfaces.
3. The shroud according to claim 1 , wherein the protrusion includes a canopy portion that at least partially covers a radially outward side of the second clearance when viewed in the radial direction.
4. The shroud according to claim 3 , wherein the canopy portion is disposed at the other side in the circumferential direction and is formed continuously with the second opposing surfaces.
5. A blade member comprising:
a blade body; and
the shroud according to claim 1 .
6. A rotary machine comprising:
a compressor that compresses outside air to generate compressed air,
a combustor that combusts fuel in the presence of compressed air to generate combustion gas, and
a turbine that is driven by high-temperature high-pressure combustion gas, wherein the turbine is provided with the blade member according to claim 5 .
7. A shroud comprising:
shroud bodies fixed to blade tips of blades mounted to a rotor body to extend in a radial direction, the shroud bodies being disposed adjacent to one another in a circumferential direction, wherein
each of the shroud bodies includes:
a first circumferential end surface which is formed on one side in the circumferential direction, and which is formed on a leading side in a rotational direction of the blades;
a second circumferential end surface which is formed on the other side in the circumferential direction, and which is formed on a trailing side in the rotational direction of the blades; and
an outer surface which is a surface facing radially outward,
the first circumferential end surface and the second circumferential end surface include:
first opposing surfaces which are adjacent shroud bodies which face one another, and which are opposing surfaces intermediated by a first clearance on an upstream side of the shroud;
second opposing surfaces which are adjacent shroud bodies which face one another, and which are opposing surfaces intermediated by a second clearance on a downstream side of the shroud; and
abutting end surfaces which are adjacent shroud bodies which abut one another, and disposed between the first opposing surfaces and the second opposing surfaces,
in the first circumferential end surface and the second circumferential end surface, the first opposing surfaces, the abutting end surfaces and the second opposing surfaces are arranged in order from the upstream to the downstream of the shroud, and
the outer surface is provided with a protrusion projecting radially outward and formed so that it extends along the second opposing surface of only the second circumferential end surface and in a direction intersecting the rotational direction of the rotor body, and includes a canopy portion that at least partially covers a radially outward side of the second clearance when viewed in the radial direction, so as to reduce the amount of combustion gas leaking through the second clearance between the adjacent shroud bodies.