Recently,closed cycle magnetohydrodynamic power generation system research has been focused on improving the isentropic efficiency and the enthalpy extraction ratio.By reducing the cross-section area ratio of the disk...Recently,closed cycle magnetohydrodynamic power generation system research has been focused on improving the isentropic efficiency and the enthalpy extraction ratio.By reducing the cross-section area ratio of the disk magnetohydrodynamic generator,it is believed that a high isentropic efficiency can be achieved with the same enthalpy extraction.In this study,the result relating to a plasma state which takes into account the ionization instability of non-equilibrium seeded plasma is added to the theoretical prediction of the relationship between enthalpy extraction and isentropic efficiency.As a result,the electron temperature which reaches the seed complete ionization state without the growth of ionization instability can be realized at a relatively high seed fraction condition.However,the upper limit of the power generation performance is suggested to remain lower than the value expected in the low seed fraction condition.It is also suggested that a higher power generation performance may be obtained by implementing the electron temperature range which reaches the seed complete ionization state at a low seed fraction.展开更多
As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle ...As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle β<sub>2B</sub> equal to 0°, 10°, 20°, 30°, 40°, and 50° were designed to evaluate the influences of impeller backsweep angle β<sub>2B</sub> on the performance, characteristics of gas flow and equivalent stress using computational fluid dynamics (CFD) and finite element analysis (FEA). Results indicated that the performance curve for the outlet backsweep blade angle β<sub>2B</sub> of 50° has the largest stable operating range. The isentropic efficiency of the impeller with backsweep angle β<sub>2B</sub> equal to 40° is 16.8% - 25.9% higher than that of the impeller with backsweep angle β<sub>2B</sub> equal to 0°. When the blade outlet backsweep angle is 30°, the equivalent stress distribution of the impeller is more uniform, the maximum equivalent stress is the smallest.展开更多
文摘Recently,closed cycle magnetohydrodynamic power generation system research has been focused on improving the isentropic efficiency and the enthalpy extraction ratio.By reducing the cross-section area ratio of the disk magnetohydrodynamic generator,it is believed that a high isentropic efficiency can be achieved with the same enthalpy extraction.In this study,the result relating to a plasma state which takes into account the ionization instability of non-equilibrium seeded plasma is added to the theoretical prediction of the relationship between enthalpy extraction and isentropic efficiency.As a result,the electron temperature which reaches the seed complete ionization state without the growth of ionization instability can be realized at a relatively high seed fraction condition.However,the upper limit of the power generation performance is suggested to remain lower than the value expected in the low seed fraction condition.It is also suggested that a higher power generation performance may be obtained by implementing the electron temperature range which reaches the seed complete ionization state at a low seed fraction.
文摘As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle β<sub>2B</sub> equal to 0°, 10°, 20°, 30°, 40°, and 50° were designed to evaluate the influences of impeller backsweep angle β<sub>2B</sub> on the performance, characteristics of gas flow and equivalent stress using computational fluid dynamics (CFD) and finite element analysis (FEA). Results indicated that the performance curve for the outlet backsweep blade angle β<sub>2B</sub> of 50° has the largest stable operating range. The isentropic efficiency of the impeller with backsweep angle β<sub>2B</sub> equal to 40° is 16.8% - 25.9% higher than that of the impeller with backsweep angle β<sub>2B</sub> equal to 0°. When the blade outlet backsweep angle is 30°, the equivalent stress distribution of the impeller is more uniform, the maximum equivalent stress is the smallest.
