Abstract: A turbine wheel or disk having a plurality of dovetail slots formed in its circumference for receiving a dovetail root of a blade such as a compressor or turbine blade. Each of the dovetail slots has a load face positioned to oppose a centrifugal load exerted by the dovetail root when a turbine is in operation. Each of the dovetail slots has a pair of opposing acute bottom corners formed between a radially inner edge of the load face and a bottom of the dovetail slot. Each of the acute bottom corners may have an undercut formed that includes a first radius of curvature and a second radius of curvature to form a clearance between the dovetail root and the dovetail slot. Each of the dovetail slots may have a curved bottom for receiving a rounded dovetail root.

Abstract: A blade retention arrangement is disclosed for retaining a blade within a disk or wheel within a turbine. The blade retention arrangement includes a dovetail connected with the blade for insertion within a dovetail slot formed in a circumference of the disk or wheel. A first chamfer is formed on an axially front bottom edge of the dovetail and a first deformation of a axially front surface of the wheel presses against the first chamfer whereby a first radially outward force is exerted on the dovetail with respect to an axis of the wheel that presses the dovetail against a first centrifugal retention surface of the dovetail slot. A second chamfer may be formed on an axially back bottom edge of the dovetail that performs in the same manner. The first and second chambers may be formed on respective ones of a forward and aft spacer, or on a bottom spacer instead of being formed on the blade dovetail directly.