Turbomachinery

A turbomachine configured to compress supercritical carbon dioxide, the turbomachine comprising, in fluid flow series:

• an inlet;
• an inducerless radial impeller having a plurality of backswept blades each of which have a blade exit angle (χ2) of from −50 to −70 degrees;
• a fully vaneless diffuser;
• and
• a volute comprising a tongue and having a flow area at the tongue equal to that of the diffuser,
• wherein a hub hade angle of the impeller at an entry thereto (γ1hub) is from 50 to 70 degrees,
• wherein the hub hade angle is defined by an axial line of the inlet and a tangent line that is tangent to a point of the impeller where the blade of the impeller begins,
• wherein the inlet is radially flared at a downstream end of the inlet adjacent to the impeller to induce a radial component in flow prior to an entry to the impeller,
• wherein only the diffuser is located between the impeller and the volute,
• wherein the plurality of blades comprises:
• a set of main blades;
• and
• a set of splitter blades,
• wherein a meridional chord length of the splitter blades (cs) is 70 percent of a meridional chord length of the main blades (cm), and
• wherein a radius of the diffuser (r3) is from 1.2 to 1.8 times larger than a radius of the impeller (r2).