舰船动力设备系统产生的持续低频振动会严重影响舰船的声隐身性能及舰船精密设备的工作性能。以自主设计研制的电磁主动吸振器为对象,为了匹配电磁主动吸振器的实际使用工况,在滤波-x最小均方(Filter-x Least Mean Square,FxLMS)控制算...舰船动力设备系统产生的持续低频振动会严重影响舰船的声隐身性能及舰船精密设备的工作性能。以自主设计研制的电磁主动吸振器为对象,为了匹配电磁主动吸振器的实际使用工况,在滤波-x最小均方(Filter-x Least Mean Square,FxLMS)控制算法中引入抑制因子,对主动控制力的输出进行限幅。首先通过数值仿真分析验证匹配优化后的控制算法对振动控制的抑制效果,然后介绍基于电磁主动吸振器工程样机搭建的主动控制实验台架系统,以单频激励工况为基础开展主动控制效果验证实验,证明电磁吸振器与匹配优化后的控制算法对低频机械振动控制的有效性。数值仿真和实验结果表明,针对自主设计研制的电磁主动吸振器而提出的匹配优化主动控制算法能够有效抑制低频机械振动响应,在时域和频域均可以取得显著的振动控制效果。展开更多
An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended und...An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended under the unit feedback control system designed with the primary dynamic model obtained. Online identification in frequency domain is processed to give the precise model. Comparisons show that the experimental method is much closer to the precise model than the theoretic method based on magnetic circuit law. So this experimental method is a good choice to build the primary dynamic model of AMSS.展开更多
The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulenc...The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.展开更多
Shape memory alloy metal rubber(SMAMR)is a novel intelligent elastic damping material which can realize the integration of structure and function.The investigations on the anisotropic mechanical characteristics which ...Shape memory alloy metal rubber(SMAMR)is a novel intelligent elastic damping material which can realize the integration of structure and function.The investigations on the anisotropic mechanical characteristics which depended on shaping craft and working temperature were conducted by quasi-static tests.Comparative experiments indicated that the heat setting temperature affect the elastic modulus non-monotonously but has little effect on the loss factor of SMAMR in both martensite and austenite phases.With the increase of the heat setting time,the elastic modulus of SMAMR monotonously decreases and the reduction of loss factor is unobvious.With the present shaping craft,SMAMR exhibits the anisotropy in moulding and non-moulding directions,which is affected by the heat setting process and working temperature.It was proved that the mechanical properties have approximately linear relationship with temperature during the phase transition process.Due to its temperature-dependent mechanical properties,SMAMR that experiences the heat setting procedure is expected to be used in active vibration control systems with varying temperature-dependent stiffness and damping coefficients to provide superior vibration control performance.展开更多
文摘舰船动力设备系统产生的持续低频振动会严重影响舰船的声隐身性能及舰船精密设备的工作性能。以自主设计研制的电磁主动吸振器为对象,为了匹配电磁主动吸振器的实际使用工况,在滤波-x最小均方(Filter-x Least Mean Square,FxLMS)控制算法中引入抑制因子,对主动控制力的输出进行限幅。首先通过数值仿真分析验证匹配优化后的控制算法对振动控制的抑制效果,然后介绍基于电磁主动吸振器工程样机搭建的主动控制实验台架系统,以单频激励工况为基础开展主动控制效果验证实验,证明电磁吸振器与匹配优化后的控制算法对低频机械振动控制的有效性。数值仿真和实验结果表明,针对自主设计研制的电磁主动吸振器而提出的匹配优化主动控制算法能够有效抑制低频机械振动响应,在时域和频域均可以取得显著的振动控制效果。
基金Supported by the National Nature Foundation of China (No.59975073)
文摘An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended under the unit feedback control system designed with the primary dynamic model obtained. Online identification in frequency domain is processed to give the precise model. Comparisons show that the experimental method is much closer to the precise model than the theoretic method based on magnetic circuit law. So this experimental method is a good choice to build the primary dynamic model of AMSS.
基金supported by Hatakeyama Grant-in-Aid(2014)of Turbomachinery of Japanthe support of Dr.Hikaru Matsumiya and Dr.Tetsuya Kogaki(National Institute of Advanced Industrial Science and Technology of Japan)for providing MEL blade data
文摘The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51105022,51101008 and 51211130115)Fan Zhou Research Fund (Grant No. 201104021)
文摘Shape memory alloy metal rubber(SMAMR)is a novel intelligent elastic damping material which can realize the integration of structure and function.The investigations on the anisotropic mechanical characteristics which depended on shaping craft and working temperature were conducted by quasi-static tests.Comparative experiments indicated that the heat setting temperature affect the elastic modulus non-monotonously but has little effect on the loss factor of SMAMR in both martensite and austenite phases.With the increase of the heat setting time,the elastic modulus of SMAMR monotonously decreases and the reduction of loss factor is unobvious.With the present shaping craft,SMAMR exhibits the anisotropy in moulding and non-moulding directions,which is affected by the heat setting process and working temperature.It was proved that the mechanical properties have approximately linear relationship with temperature during the phase transition process.Due to its temperature-dependent mechanical properties,SMAMR that experiences the heat setting procedure is expected to be used in active vibration control systems with varying temperature-dependent stiffness and damping coefficients to provide superior vibration control performance.
