喉部面积对盘式磁流体发电机性能影响分析

Effect of Throat Area on Performance of Disk Magnetohydrodynamic Generator

盘式磁流体发电机因其热效率高、功率密度大等优点在空间探测等领域受到了研究学者的广泛关注。在盘式通道中,喷嘴喉部对通道内等离子体具有加速和电离作用,是整个发电系统的关键部件之一。喷嘴喉部面积的变化会改变发电通道中磁流体流动特性及等离子体电离特性,进而影响发电机性能。通过非平衡准一维数值模拟分析了喷嘴喉部面积对盘式磁流体发电机性能影响。结果表明:适宜的喷嘴喉部面积可以使发电通道等离子体维持在较高的马赫数下,电子温度适中,电导率较高,可以提高非平衡等离子体电离的稳定性,使发电机具有更高的性能,获得高焓提取率及等熵效率。

Disk magnetohydrodynamic(MHD)generators have attracted the extensive attention from researchers in the fields of space exploration due to their high thermal efficiency and high-power density.The nozzle throat has the effect of accelerating and ionizing the plasma in the disk channel,and is one of the key components of the entire power generation system.The change of the nozzle throat area will cause the MHD flow characteristics and plasma ionization characteristics,and then affect the performance of the generator.The effect of the nozzle throat area on the performance of disk MHD generator was analyzed by nonequilibrium quasi-one-dimensional numerical simulation.The results show that the proper throat area can maintain the plasma at a higher Mach in the channel,the electron temperature is moderate,the plasma electrical conductivity is high,and the stability of the nonequilibrium plasma can be improved,which can make the generator has a higher performance,and a higher enthalpy extraction and isentropic efficiency can obtain.