Compressor for CO2 cycle with at least two cascade compression stages for assuring supercritical conditions

A compressor arranged to process a CO2 flow, comprising:

• a first compressor stage comprising a first row of rotary blades with a first number of blades;
• a second compressor stage comprising a second row of rotary blades with a second number of blades, the second compressor stage being fluidly connected downstream the first compressor stage,
• wherein the first number of blades is less than the second number of blades,
• wherein the first stage is arranged to provide at outlet the CO2 flow in supercritical condition,
• wherein the first row of rotary inducer blades is arranged to provide the CO2 flow directly to the second row of blades,
• wherein the second row of blades is axially spaced from the first row of blades to form an annular gap between the first row of blades and the second row of blades, and
• wherein the annular gap is empty space that does not have features that contact the CO2 flow from the first stage to the second stage, and
• wherein the annular gap has an axial length between one and two times a trailing edge height of the first row of blades.