US Patent 10962021 Non-axisymmetric impeller hub flowpath

A centrifugal impeller is disclosed having a non-axisymmetric flowpath surface. The centrifugal compressor may comprise a hub and a plurality of circumferentially spaced vanes. The hub has a flowpath surface and an axis of rotation. The plurality of circumferentially spaced vanes extend from the flowpath surface, with each of the vanes having a pressure-side fillet and a suction-side fillet extending from a leading edge to a trailing edge of the vane. The pressure-side fillet and suction-side fillet intersect the flowpath surface at a runout. The runout of the pressure-side fillet of a first vane is asymmetric to the runout of the suction-side fillet of the first vane.