In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separat...In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separation spring-driven opening scheme is proposed to achieve rapid and reliable opening of the front cover.The mathematical model of the opening process of the front cover is established by the rigid body dynamics theory.To establish a response surface model to optimize the opening scheme,three main influencing factors of the opening process are obtained through the designed experiments,including the pre-compression,the stiffness of the thrust spring,and the thrust spring force arm length.In addition,the prescribed kinematic law was taken as constraint,and the smaller thrust spring preliminary pressure and angular velocity was taken as optimization expectations.The results show that the opening scheme meets the design requirements on opening process well.It also shows that the optimized scheme can reduce the kinetic energy of the front cover,and the impact on the canister effectively,achieving a reliable and rapid opening of the front cover.展开更多
Air-conditioning system consumes a large amount of electricity in residential sections,and its efficiency has drawn extensive concerns in energy-conscious era.Liquid-vapor separation is a heat transfer enhancement tec...Air-conditioning system consumes a large amount of electricity in residential sections,and its efficiency has drawn extensive concerns in energy-conscious era.Liquid-vapor separation is a heat transfer enhancement technology that can effectively improve the performance of the heat exchanger as well as the system.In this paper,a regular air-conditioning system as the baseline(system-A)and other two air-conditioning systems with liquid-vapor separation heat exchanger(system-B and system-C)are comparatively studied.The component behaviors and system performances are deeply explored by using advanced exergy analysis with a focus on quantifying how much consequences come from the variants,i.e.liquid-vapor separation.The results indicate that the system-B has large reduced exergy destruction from the compressor and condenser at cooling mode relative to the system-A.The system-C has mainly diminished exergy destruction in the compressor caused by other components relative to the system-B.At heating mode,the system-C has an enhanced system exergy efficiency of 9.6%over the system-A,and it also has the decreased avoidable exergy destruction which is dominantly contributed by the compressor and evaporator.Furthermore,it is found that liquid-vapor separation mainly benefits the compressor and outdoor heat exchanger where it locates,leading to the system performance improvements.展开更多
文摘In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separation spring-driven opening scheme is proposed to achieve rapid and reliable opening of the front cover.The mathematical model of the opening process of the front cover is established by the rigid body dynamics theory.To establish a response surface model to optimize the opening scheme,three main influencing factors of the opening process are obtained through the designed experiments,including the pre-compression,the stiffness of the thrust spring,and the thrust spring force arm length.In addition,the prescribed kinematic law was taken as constraint,and the smaller thrust spring preliminary pressure and angular velocity was taken as optimization expectations.The results show that the opening scheme meets the design requirements on opening process well.It also shows that the optimized scheme can reduce the kinetic energy of the front cover,and the impact on the canister effectively,achieving a reliable and rapid opening of the front cover.
基金supported by State Key Program of National Natural Science Foundation of China(51736005)Science and Technology Program of Guangzhou(201704030108)+1 种基金Foshan Municipal Science and Technology Bureau Project(2015IT100162)Guangdong Special Support Program(2017TX04N371)。
文摘Air-conditioning system consumes a large amount of electricity in residential sections,and its efficiency has drawn extensive concerns in energy-conscious era.Liquid-vapor separation is a heat transfer enhancement technology that can effectively improve the performance of the heat exchanger as well as the system.In this paper,a regular air-conditioning system as the baseline(system-A)and other two air-conditioning systems with liquid-vapor separation heat exchanger(system-B and system-C)are comparatively studied.The component behaviors and system performances are deeply explored by using advanced exergy analysis with a focus on quantifying how much consequences come from the variants,i.e.liquid-vapor separation.The results indicate that the system-B has large reduced exergy destruction from the compressor and condenser at cooling mode relative to the system-A.The system-C has mainly diminished exergy destruction in the compressor caused by other components relative to the system-B.At heating mode,the system-C has an enhanced system exergy efficiency of 9.6%over the system-A,and it also has the decreased avoidable exergy destruction which is dominantly contributed by the compressor and evaporator.Furthermore,it is found that liquid-vapor separation mainly benefits the compressor and outdoor heat exchanger where it locates,leading to the system performance improvements.