Supercritical carbon dioxide (S-CO
2) gas turbines can generate power at high cycle thermal efficiency, even at modest temperatures of 500-550°C, because of the markedly reduced compressor work near the critical point. Furthermore, the reaction between Na and CO
2 is milder than that between H
2O and Na. A more reliable and economically advantageous power generation system could be achieved by coupling with a sodium-cooled fast reactor. At Tokyo Institute of Technology, numerous development projects have been conducted for development of this system in cooperation with JAEA. Supercritical CO
2 compressor performance test results were obtained as described herein. Maximum design conditions of the supercritical CO
2 test apparatus are 11 MPa pressure, 150°C temperature, a 6 kg/s flow rate, and a rotation rate of 24,000 rpm. Different compressor design points are examined using impellers of three kinds. Then test data were obtained under steady-state conditions. The pressure ratio (compressor outlet pressure/inlet pressure) was obtained with the function of compressor rotation speed and the fluid flow rate. The data, reported herein for the first time, cover a broad region from sub-critical to supercritical pressures. No unstable phenomenon was observed in the area where the CO
2 properties change sharply. Results show that enthalpy rise needed to achieve the same pressure ratio near the critical point is smaller than in a sub-critical condition. Compressor test data were calculated using three-dimensional CFD code (CFX). Data of the pressure ratio vs. flow rate agreed with those implied by the fundamental compressor theory.
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