Impeller blade with reduced stress
AssigneePraxair Technology, Inc.
InventorMichael J. Stanko
Life of this patent
Estimating the term…
Abstract
A fluid impeller blade with lowered stress and increased useful life has an edge extending from the hub of the blade and forming, in part, a boundary for axial fluid flow. The edge, at least at its extremity, is spaced axially into the blade, at an angle of about 0.5.degree. to about 20.degree. from the radial line through the edge at the hub of the blade, whereby the mass of blade material exerting centrifugal force on the edge at the blade hub during rotation of the impeller is reduced.
Claims10
A radial flow turbine blade with reduced stress and increased useful life comprising a surface for fluid engagement having a blade hub, an outer shroud and an edge defining, in part, an outlet opening for axial fluid flow, said edge extending from said blade hub to the outer radial extremity of said shroud, and at least at its outer radial extremity being spaced axially into the blade at an angle of about 0.5.degree. to about 8.degree. from the radial line through said edge at the hub of said blade.
A radial expansion impeller comprising blades each with an outer shroud wherein the impeller face having outlet openings for axial flow, at least near its radial extremity, has the shape of the surface of a cone with its vertex on the impeller centerline, the vertex having an included angle from about 179.degree. to about 170.degree..
A method of reducing centrifugal stress in a shrouded radial flow turbine blade at the hub of the blade edge forming, in part, an outlet opening for axial flow, said method comprising spacing at least the extremity of said edge axially into the blade at an angle of about 0.5.degree. to about 8.degree. from a radial line through said edge at the hub of said blade.
Dependencies are inferred from the claim text.