Up-Grade Bypass Controlled Supercritical CO2 Gas Turbine for 0.6 GW(th) FFHR Series Fusion Reactors

For the purpose of further improving the power generation performance by the supercritical CO2 gas turbine power generation system, aerodynamic optimum and heat transfer flow analysis were carried out for vertical single-axial bypass control type supercritical CO2 gas turbine power generation system model in the 0.6 GW class FFHR-b1 nuclear fusion power reactor model. As a result, the following conclusions were obtained. (1) Since the outlet temperature of the 5-stage final stage of the improved main compressor as an alternative to the low/high pressure compressor can be lowered to 318 K compared to the conventional design (outlet temperature 334 K), there are design cases that do not require an intercooler in the conventional design. (2) As a result of reviewing the structural design and operating conditions of the turbine, the output increased by about 1.1%. (3) Since a compact design with a total length of about 2.2 m is possible in the design of the above CO2 gas turbine power generation system (excluding the generator), the feasibility of designing a vertical single-axial bypass control type supercritical CO2 gas turbine power generation system is clarified. From these results, the redesigned vertical uniaxial bypass control type supercritical CO2 gas turbine power generation system is expected to be a compact and economical power generation system that exceeds the power generation efficiency of the conventional design model up to about 0.6%. (C) 2022 The Japan Society of Plasma Science and Nuclear Fusion Research