Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of ...Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of the structure,and is widely used in the main flight control surface of large and medium-sized civil airliners.In order to restrain the flutter of aircraft rudder surface,it is necessary to design the servo stiffness of the kick-reaction link actuator in the development stage,so that it can meet the dynamic stiffness requirement within the frequency range.Taking the actuator of a civil airliner as the research object,the dynamic stiffness modeling of elevator actuator is carried out on MATLAB platform,and the dynamic stiffness test is carried out to verify the correctness of dynamic stiffness modeling.The simulation and test results show that the actuator can meet the dynamic stiffness design requirements.展开更多
Due to the instability of FeO at temperatures below 843 K,the fuidization reduction pathway of iron ore powder changes with the reduction temperature.Thus,the effect of temperature and reaction pathway interaction on ...Due to the instability of FeO at temperatures below 843 K,the fuidization reduction pathway of iron ore powder changes with the reduction temperature.Thus,the effect of temperature and reaction pathway interaction on the kinetics of fuidization reduction of iron ore powder under low-temperature conditions ranging from 783 to 903 K was investigated to describe the fluidization reduction rate of iron ore powder from three aspects:microstructure change,reaction limiting link,and apparent activation energy of the reaction,exploring their internal correlation.The experimental results revealed that in a temperature range of 783-813 K,the formation of a dense iron layer hindered the internal diffusion of reducing gas,resulting in relatively high gas diffusion resistance.In addition,due to the differences in limiting links and reaction pathways in the intermediate stage of reduction,the apparent activation energy of the reaction varied.The apparent activation energy of the reaction ranged from 23.36 to 89.13 kJ/mol at temperature ranging from 783 to 813 K,while it ranged from 14.30 to 68.34 kJ/mol at temperature ranging from 873 to 903 K.展开更多
文摘Under the same aerodynamic load,the load transmitted by the kick-reaction link actuator to the aircraft structure is only 1/5 to 1/3 of that of the point-to-point actuator,which can significantly reduce the weight of the structure,and is widely used in the main flight control surface of large and medium-sized civil airliners.In order to restrain the flutter of aircraft rudder surface,it is necessary to design the servo stiffness of the kick-reaction link actuator in the development stage,so that it can meet the dynamic stiffness requirement within the frequency range.Taking the actuator of a civil airliner as the research object,the dynamic stiffness modeling of elevator actuator is carried out on MATLAB platform,and the dynamic stiffness test is carried out to verify the correctness of dynamic stiffness modeling.The simulation and test results show that the actuator can meet the dynamic stiffness design requirements.
基金The authors gratefully acknowledge financial support by the National Natural Science Foundation of China-Xinjiang Joint Fund(U2003124)the National Natural Science Foundation of China(No.51974001)the University Outstanding Young Talents Funding Program(No.gxyq2019016).
文摘Due to the instability of FeO at temperatures below 843 K,the fuidization reduction pathway of iron ore powder changes with the reduction temperature.Thus,the effect of temperature and reaction pathway interaction on the kinetics of fuidization reduction of iron ore powder under low-temperature conditions ranging from 783 to 903 K was investigated to describe the fluidization reduction rate of iron ore powder from three aspects:microstructure change,reaction limiting link,and apparent activation energy of the reaction,exploring their internal correlation.The experimental results revealed that in a temperature range of 783-813 K,the formation of a dense iron layer hindered the internal diffusion of reducing gas,resulting in relatively high gas diffusion resistance.In addition,due to the differences in limiting links and reaction pathways in the intermediate stage of reduction,the apparent activation energy of the reaction varied.The apparent activation energy of the reaction ranged from 23.36 to 89.13 kJ/mol at temperature ranging from 783 to 813 K,while it ranged from 14.30 to 68.34 kJ/mol at temperature ranging from 873 to 903 K.
