摘要
A MHD generator with different arrangements of electromagnetic fields will lead the generator working in three modes.A quasi-one-dimensional approximation is used for the model of the MHD generator to analyze the inner mechanism of operation modes.For the MHD generator with a uniform constant magnetic field,a specific critical electric field E_(cr) is required to decelerate a supersonic entrance flow into a subsonic exit flow.Otherwise,the generator works in a steady mode with a larger electric field than E_(cr) in which a steady supersonic flow is provided at the exit,or the generator works in a choked mode with a smaller electric field than E_(cr) in which the supersonic entrance flow is choked in the channel.The detailed flow field characteristics in different operation modes are discussed,demonstrating the relationship of operation modes with electromagnetic fields.
A MHD generator with different arrangements of electromagnetic fields will lead the generator working in three modes.A quasi-one-dimensional approximation is used for the model of the MHD generator to analyze the inner mechanism of operation modes.For the MHD generator with a uniform constant magnetic field,a specific critical electric field E_（cr） is required to decelerate a supersonic entrance flow into a subsonic exit flow.Otherwise,the generator works in a steady mode with a larger electric field than E_（cr） in which a steady supersonic flow is provided at the exit,or the generator works in a choked mode with a smaller electric field than E_（cr） in which the supersonic entrance flow is choked in the channel.The detailed flow field characteristics in different operation modes are discussed,demonstrating the relationship of operation modes with electromagnetic fields.
基金
supported in part by the National Natural Science Foundation of China under Grant 51006027,Grant 50925625,and Grant 51437002
the Natural Scientific Research Innovation Foundation in Harbin Institute of Technology under Grant HIT.NSRIF.2009091
the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant 20102302120047
