Fluid machine
AssigneeKabushiki Kaisha Toshiba
InventorsHideyuki Kawajiri, Naritoshi Nakagawa
Life of this patent
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Abstract
A fluid machine of an embodiment includes a sealing portion formed of an annular minute gap between a runner band of a runner configuring a rotating portion and a sealing liner which is a stationary portion and arranged in opposition to the runner band. A groove having a quadrangular cross-sectional shape is formed circumferentially on a surface of the sealing liner configuring the sealing portion. In a cross section perpendicular to a groove forming direction of the groove, an angle θ, formed between a side WU of the groove on the most upstream side with respect to the flowing direction of the leakage flow and a side W0 of the groove which is on an extended line of the surface of the sealing liner, is determined to be 15° or more and 40° or less.
Claims15
A fluid machine, comprising:
- a rotating portion having a plurality of blades and an annular member disposed circumferentially at one end of the blades, the annular member having an annular wall portion;
- a stationary portion arranged in opposition to the annular member, the stationary portion having a stationary wall portion in opposition to the annular wall portion;
- a sealing portion formed of an annular minute gap between the rotating portion and the stationary portion;
- and
- a groove portion circumferentially formed on the annular wall portion of the annular member or the stationary wall portion of the stationary portion, the groove portion having a cross-sectional shape of an n-angled shape (n=3 or more) on a meridional cross section of the annular member, the groove portion having an angle θ from 15° to 40° formed between:
- a side W0 on a line of intersection of the meridional cross section and a wall surface of the annular wall portion or the stationary wall portion;
- and a side WU on a line of intersection of the meridional cross section and a wall surface inside the groove portion on a most upstream side with respect to a flowing direction of a leakage flow in the sealing portion,
- wherein the sealing portion includes a passage wherein the annular minute gap between the annular wall portion and the stationary wall portion has a substantially constant width except at the groove portion, the passage having a length greater than side W0, and
- wherein the annular minute gap between the annular wall portion and the stationary wall portion has a cross-sectional area expanding moderately at the groove portion.
A fluid machine, comprising:
- a rotating portion having a plurality of blades and an annular member disposed circumferentially at one end of the blades;
- a stationary portion arranged in opposition to the annular member;
- a sealing portion formed of an annular minute gap between the rotating portion and the stationary portion;
- and
- at least one groove portion circumferentially formed on a wall portion of the annular member or the stationary portion, the groove portion having a shape with one curve Z0 along a surface of the wall portion in a horizontal cross section and at least two sides in the horizontal cross section, the groove portion having an angle γ from 15° to 40° formed between:
- a side ZU on a line of intersection of the horizontal cross section and a wall surface inside the groove portion on a most upstream side with respect to a flowing direction of a leakage flow flowing circumferentially in the horizontal cross section;
- and a tangent line to the curve Z0 at an intersection of the curve Z0 and the side ZU.
Dependencies are inferred from the claim text.