Centrifugal rotary machine

A centrifugal rotary machine comprising:

• impellers which are provided in a plurality of stages along an axial direction and discharge a working fluid sucked from a first side in the axial direction to an outside in a radial direction of an axis;
• and
• a casing which is provided to surround the impellers and forms a flow path which leads the working fluid discharged from an upstream-side impeller positioned on the first side in the axial direction to a downstream-side impeller positioned on a second side in the axial direction,
• wherein the flow path includes
• a return bend portion which guides the working fluid to an inside in the radial direction by reversing the working fluid discharged to an outside in the radial direction from the upstream-side impeller, and
• a guiding flow path which is connected to a downstream side of the return bend portion and leads the working fluid to the inside in the radial direction so as to guide the working fluid to the downstream-side impeller,
• wherein the centrifugal rotary machine further comprises a plurality of return vanes which are provided in the guiding flow path guiding the working fluid in at least one impeller from among the impellers provided in the plurality of stages and which are provided at intervals in a circumferential direction around the axis, and
• wherein in each return vane, a trailing edge positioned on the inside in the radial direction is formed such that a second end portion on the second side in the axial direction is positioned closer to the inside in the radial direction than a first end portion on the first side in the axial direction.