【摘要】 超临界二氧化碳（SCO₂）布雷顿循环是一种极具发展前景的可用于核动力舰船的循环系统。离心压缩机是SCO₂布雷顿循环的关键部件之一,具有体积小、效率高的优点。但二氧化碳临界点附近物理性质的剧烈变化导致压缩机的设计面临诸多挑战,目前针对核动力舰船使用的大流量系数SCO₂压缩机的气动设计和分析还很少。本文采用双区模型方法对大流量系数SCO₂压缩机进行气动设计,通过求解三维定常可压缩雷诺平均Navier-Stokes（RANS）方程对所设计的压缩机性能进行了计算。结果表明:在设计工况下,SCO₂压缩机的等熵效率为90.38%,总压比为2.97,并且在非设计工况下也具有较好的气动性能;三维数值模拟预测结果验证了大流量系数压缩机的气动设计和双区模型方法的有效性。研究工作对推动SCO₂压缩机在舰船动力系统上的应用具有重要的参考价值。更多还原

【Abstract】 Supercritical carbon dioxide（SCO₂） Brayton cycle is a promising nuclear power system choice in shipboard application. Centrifugal compressor is one of the key components of SCO₂ Brayton cycle, which has the advantages of small size and high efficiency. However, compressor design challenges raised by the dramatic changes of physical property around CO₂ critical point, and quite few efforts were so far devoted to aerodynamic design of high flowcoefficient SCO₂ compressortailoredtothenuclear-poweredshipboardusage.Herewefirstlycarriedoutaerodynamic design of the SCO₂ compressor with high flow coefficient by using the two-zone model. Then, aerodynamic performance of the designed compressor is obtained by solving the 3D steady compressible Reynolds-averaged NavierStokes（RANS）equations.Theresultsshowthatthedesigned SCO₂ compressorhasthegoodoff-designoperationperformance and isentropic efficiency of the compressor is 90.38% and the total pressure ratio is 2.97 at the design condition. Threedimensional CFD predictions verify the aerodynamic design of the compressor with high flow coefficient and effectiveness of the two-zone model. This work is of certain significance to promote the application of SCO₂ compressor in shipboard usage.更多还原