依据《Design Handbook for API 6A,16Aand 17DEquipment》,《Machinery’s Handbook》和《ASME锅炉和压力容器规范》,对泥线悬挂器进行结构设计和理论计算。应用有限元分析软件,采用直接求解法,分别对泥线悬挂器和送入工具进行承压和...依据《Design Handbook for API 6A,16Aand 17DEquipment》,《Machinery’s Handbook》和《ASME锅炉和压力容器规范》,对泥线悬挂器进行结构设计和理论计算。应用有限元分析软件,采用直接求解法,分别对泥线悬挂器和送入工具进行承压和承载力学分析,得到了应力分布云图,对产品的结构进行分析,验证设计的可靠性。进行样机性能鉴定试验,完成了承压和悬载试验,实现产品设计确认。展开更多
NOKIA—021155/2《架空电缆金具》是芬兰参照 IEC、德国 VDE、瑞典 SS 等标准结合芬兰实践经验编制的。该标准所涉及的金具有连接器、绝缘罩、悬挂线夹、终端线夹、间隔线夹、固定螺钉和挂钩等,每一种均规定了型式试验要求和试验方法。...NOKIA—021155/2《架空电缆金具》是芬兰参照 IEC、德国 VDE、瑞典 SS 等标准结合芬兰实践经验编制的。该标准所涉及的金具有连接器、绝缘罩、悬挂线夹、终端线夹、间隔线夹、固定螺钉和挂钩等,每一种均规定了型式试验要求和试验方法。目前我国尚未制订这方面的标准,现特将其介绍,供参考。展开更多
The linear stability of fiber suspensions between two concentric cylinders rotating independently is studied. The modified stability equation is obtained based on the fiber orientation model and Hinch-Leal closure app...The linear stability of fiber suspensions between two concentric cylinders rotating independently is studied. The modified stability equation is obtained based on the fiber orientation model and Hinch-Leal closure approximation. The primary instabilities and bicritical curves have been calculated numerically. The critical Reynolds number,wavenumber and wave speeds of fiber suspensions as functions of the aspect ratio,volume concentration of the fibers and the gap width of cylinders are obtained.展开更多
Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applicatio...Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applications. In this paper, based on considering the influence of factors such as, seat and passengers, a MDOF(multi-degree-of-freedom) model describing the vehicle motion is set up. The MODF model, which is 8DOF of four independent suspensions and four wheel tracks, is more applicable by comparison of its analysis result with some conventional vehicle models. Therefore, it is more suitable to use the 8DOF full-car model than a conventional 4DOF half-car model in the active control design for car vibration. Based on the derived 8DOF model, a controller is designed by using LQ (linear quadratic ) control theory, and the appropriate control scheme is selected by testing various performance indexes. Computer simulation is carried out for a passenger car running on a road with step disturbance and random road disturbance expressed by Power Spectral Density (PSD). Vibrations corresponding to ride comfort are derived under the foregoing road disturbances. The response results for uncontrolled and controlled system are compared. The response of vehicle vibration is greatly suppressed and quickly damped, which testifies the effect of the active suspension. The results achieved for various controllers are compared to investigate the influence of different control schemes on the control effect.展开更多
The suspension of electrodynamic loudspeakers includes a surround of the cone and a spider, and it is characterized by the mechanic stiffness in the lumped-parameter model. By solving the nonlinear differential equati...The suspension of electrodynamic loudspeakers includes a surround of the cone and a spider, and it is characterized by the mechanic stiffness in the lumped-parameter model. By solving the nonlinear differential equation of motion which considers the nonlinearity of suspension at low frequencies numerically and measuring different kinds of surrounds and spiders, the nonlinear behavior of suspension is theoretically and experimentally studied. Since the nonlinear stiffness of spiders and surrounds can be measured and fitted respectively before assembled into loudspeakers, which spider works best with which surround is studied. The performance of loudspeakers such as harmonic distortion based on the nonlinear parameters can be predicted.展开更多
文摘依据《Design Handbook for API 6A,16Aand 17DEquipment》,《Machinery’s Handbook》和《ASME锅炉和压力容器规范》,对泥线悬挂器进行结构设计和理论计算。应用有限元分析软件,采用直接求解法,分别对泥线悬挂器和送入工具进行承压和承载力学分析,得到了应力分布云图,对产品的结构进行分析,验证设计的可靠性。进行样机性能鉴定试验,完成了承压和悬载试验,实现产品设计确认。
基金Project (Nos. 10632070 and 40231017) supported by the National Natural Science Foundation of China
文摘The linear stability of fiber suspensions between two concentric cylinders rotating independently is studied. The modified stability equation is obtained based on the fiber orientation model and Hinch-Leal closure approximation. The primary instabilities and bicritical curves have been calculated numerically. The critical Reynolds number,wavenumber and wave speeds of fiber suspensions as functions of the aspect ratio,volume concentration of the fibers and the gap width of cylinders are obtained.
文摘Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applications. In this paper, based on considering the influence of factors such as, seat and passengers, a MDOF(multi-degree-of-freedom) model describing the vehicle motion is set up. The MODF model, which is 8DOF of four independent suspensions and four wheel tracks, is more applicable by comparison of its analysis result with some conventional vehicle models. Therefore, it is more suitable to use the 8DOF full-car model than a conventional 4DOF half-car model in the active control design for car vibration. Based on the derived 8DOF model, a controller is designed by using LQ (linear quadratic ) control theory, and the appropriate control scheme is selected by testing various performance indexes. Computer simulation is carried out for a passenger car running on a road with step disturbance and random road disturbance expressed by Power Spectral Density (PSD). Vibrations corresponding to ride comfort are derived under the foregoing road disturbances. The response results for uncontrolled and controlled system are compared. The response of vehicle vibration is greatly suppressed and quickly damped, which testifies the effect of the active suspension. The results achieved for various controllers are compared to investigate the influence of different control schemes on the control effect.
基金supported by the National Natural Science Foundation of China(Grant No. 11274172)
文摘The suspension of electrodynamic loudspeakers includes a surround of the cone and a spider, and it is characterized by the mechanic stiffness in the lumped-parameter model. By solving the nonlinear differential equation of motion which considers the nonlinearity of suspension at low frequencies numerically and measuring different kinds of surrounds and spiders, the nonlinear behavior of suspension is theoretically and experimentally studied. Since the nonlinear stiffness of spiders and surrounds can be measured and fitted respectively before assembled into loudspeakers, which spider works best with which surround is studied. The performance of loudspeakers such as harmonic distortion based on the nonlinear parameters can be predicted.
