To solve the control allocation problem of dual aero/jet vane control missile, dynamics e- quations in longitudinal plane are derived, and the structure of compound control loop is designed based on attitude autopilot...To solve the control allocation problem of dual aero/jet vane control missile, dynamics e- quations in longitudinal plane are derived, and the structure of compound control loop is designed based on attitude autopilot. Four brief compound control allocation strategies are researched and an- alyzed. Furthermore, a new strategy called chain combination variable proportional coefficient strat- egy based on rudder effect is presented. By simulation of initial climb trajectory, the characteristics of all the strategies are researched, and the results illustrate that the new strategy can meet the re- quirement well.展开更多
Different guide vane structures will affect the flow inside the pump,and then affect the transformation of the pressure energy and kinetic energy,and change the velocity distribution of the pump outlet.In order to stu...Different guide vane structures will affect the flow inside the pump,and then affect the transformation of the pressure energy and kinetic energy,and change the velocity distribution of the pump outlet.In order to study the influence of long and short guide vanes on the water-jet pump,on the basis of conventional design,eight schemes of guide vane with different vertical heights were designed in the method of computational fluid dynamics for numerical calculation,the performance curve of water-jet pumps with different long and short guide vanes was obtained,and finally the influence of different guide vanes on hydraulic performance and internal flow was analyzed.The results show that all of schemes reducing the height of blade can improve the head and efficiency.In the schemes reducing the height on the shroud,the guide vanes that the height of the blade is equal to the height difference between hub and shroud in impeller have the highest head and efficiency.In all schemes decreasing the blade height,with the increase of the height difference,the velocity increases gradually and the distribution of turbulence kinetic energy becomes more reasonable in the guide vane outlet.The schemes reducing the height on the hub have more reasonable distribution of velocity and turbulence kinetic energy according to schemes reducing the height on the shroud.The guide vanes of long and short blades can be used to stagger the position of the diffusion flow generated by adjacent blades,which can reduce the effect of the velocity circulation and make the flow of the outlet position more stable.展开更多
文摘To solve the control allocation problem of dual aero/jet vane control missile, dynamics e- quations in longitudinal plane are derived, and the structure of compound control loop is designed based on attitude autopilot. Four brief compound control allocation strategies are researched and an- alyzed. Furthermore, a new strategy called chain combination variable proportional coefficient strat- egy based on rudder effect is presented. By simulation of initial climb trajectory, the characteristics of all the strategies are researched, and the results illustrate that the new strategy can meet the re- quirement well.
基金The Fundamental Research Funds for the Central Universities(JD2016XGKP1062)
文摘Different guide vane structures will affect the flow inside the pump,and then affect the transformation of the pressure energy and kinetic energy,and change the velocity distribution of the pump outlet.In order to study the influence of long and short guide vanes on the water-jet pump,on the basis of conventional design,eight schemes of guide vane with different vertical heights were designed in the method of computational fluid dynamics for numerical calculation,the performance curve of water-jet pumps with different long and short guide vanes was obtained,and finally the influence of different guide vanes on hydraulic performance and internal flow was analyzed.The results show that all of schemes reducing the height of blade can improve the head and efficiency.In the schemes reducing the height on the shroud,the guide vanes that the height of the blade is equal to the height difference between hub and shroud in impeller have the highest head and efficiency.In all schemes decreasing the blade height,with the increase of the height difference,the velocity increases gradually and the distribution of turbulence kinetic energy becomes more reasonable in the guide vane outlet.The schemes reducing the height on the hub have more reasonable distribution of velocity and turbulence kinetic energy according to schemes reducing the height on the shroud.The guide vanes of long and short blades can be used to stagger the position of the diffusion flow generated by adjacent blades,which can reduce the effect of the velocity circulation and make the flow of the outlet position more stable.
