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变惯量飞轮-液压变压器-马达辅助液压激振
Hydro-Vibration Assisted by Flywheel-Hydraulic transformer-Motor
 [PDF]

吕云嵩,王育荣,邹政耀
- , 2015,
Abstract: 针对阀控液压激振低能效的缺陷,提出一种新的激振方法。以作动缸、液压变压器和液压马达组成闭式回路,作动缸活塞杆连接振体,液压马达传动轴连接变量飞轮。振体振动时带动作动缸输出交变压力油,经变压器变压,驱动液压马达和飞轮摆动。飞轮摆动时其转动惯量能够跟踪振体运动节奏变化,在飞轮和振体之间引发动量循环,强化振动。动量循环没有节流损失,故而节能。液压变压器变压比调节范围大,弥补了大排量液压马达高频特性不良的缺陷,能有效扩展振动特性调节范围。构建了系统数学模型,对激振系统动力学性能进行了理论分析和Matlab仿真,表明变量飞轮的激振效果可通过变压系数和飞轮惯量调节系数调节,在适当条件下激振效果明显。
In view of the low energy efficiency of the hydro-vibration controlled by valve, a new method of vibration is put forward. An actuator and a hydro-motor constitute a closed circuit via a hydro-transformer. A vibrator is connected to the actuator, and the hydro-motor is connected to a variable inertia flywheel. When the vibrator vibrates, the actuator will be driven to pump alternating pressure oil, the motor with the flywheel is then driven to swing via the hydro-transformer. The rotating inertia of the flywheel can be changed according to the motion phase of the vibrator, momentum cycles will thus arise between the flywheel and the vibrator and theirs vibration is intensified. There is no throttling loss in this way unlike the vibration controlled by valve, it is energy saving. Having large adjusting range in transformer ratio the transformer could compensate the insufficient performance of the motor of large displacement at high frequency, and the adjusting range of vibration frequency could be extended. Theoretical analysis and Matlab simulation shows that the vibration could be adjusted by the transformer ratio and the rate of momentum change of the flywheel, and the vibration can be intensified obviously under proper conditions
结构动力计算中振型叠加法的进一步研究  [PDF]
林继德
工程力学 , 1992,
Abstract: 计算结果表明,用一般的振型叠加法计算无质量处的位移是不正确的。为了解决这个问题,本文给出修正的振型叠加法.用该方法计算的结果完全符合问题的精确解。本文还给出了该方法的严格理论证明。
鄂尔多斯盆地下奥陶统原生—同层沥青分析  [PDF]
吴征,杨元初,王新红
天然气工业 , 1999,
Abstract: ?通过对盆地北部近百件下奥陶统马家沟组碳酸盐岩的有机岩石学观察发现,碳酸盐岩中的沥青赋存形式多样,大致可分为基质型和充填型.前者呈分散状、絮状和顺层分布状等;后者则主要为孔洞型(晶间孔、晶间溶孔和膏膜孔)和裂缝型(缝和线、构造缝等).根据上述各种沥青赋存形式(产状)和烃类色层效应将这些沥青划属原生-同层沥青.并认为普遍存在的基质型沥青代表了碳酸盐岩中原始有机质的输入和向油气的转化(形成原生沥青);而充填型沥青则指示了新生成油气的排驱和初次运移(相应形成初次运移沥青).正是这种原生沥青和初次运移沥青的共同存在,对碳酸盐岩烃源岩的确认提供了最直观可信的岩石学依据.此外,从原生-同层沥青含量和残余有机碳、热解生烃潜量等大致呈正相关变化中,进一步说明了原生-同层沥青含量可作为碳酸盐岩(尤其是高演化碳酸盐岩)烃源岩评价的重要指标.据此,对盆地北部马家沟组碳酸盐岩进行了生烃潜力评价.
可刚性固定的同振圆柱型矢量水听器的设计  [PDF]
刘爽,李琪,贾志富,刘勇
哈尔滨工程大学学报 , 2014, DOI: 10.3969/j.issn.1006-7043.201401012
Abstract: 针对同振型矢量水听器使用弹簧悬挂不便的问题,提出一种采用圆环型橡胶弹簧作为悬置元件的新型可刚性固定式同振圆柱型矢量水听器的设计方案。该水听器可直接固定在水下平台用于测量水下声波质点加速度信号。推导了内置加速度计的该型水听器的声压灵敏度表达式。通过理论计算出橡胶弹簧的剪切刚度,并应用有限元软件ANSYS对剪切刚度进行了仿真分析并制作了水听器样机。在0.5~2.5 kHz的频率范围内,对矢量水听器的声压灵敏度和指向性进行了测量。1 kHz时,声压灵敏度为-188 dB。测量频带内,指向性凹点深度均大于20 dB。实验结果表明,此种结构的矢量水听器可以实现刚性固定的目的。
求强非线性自治振子同宿轨的广义Padé逼近方法  [PDF]
李震波,唐驾时,蔡萍
力学学报 , 2013, DOI: 10.6052/0459-1879-12-277
Abstract: 在经典Padé逼近理论的基础上进行了相应推广,提出了广义Padé逼近方法,并针对强非线性自治振子同宿轨的求解问题,利用双曲函数构造了一种新的广义Padé逼近式.首先,该广义Padé逼近式有着较简单的泰勒展开式,与现有的Padé逼近式相比,在计算同阶逼近时,计算量更少;其次,该方法在强非线性时,依然有着较高的精度;第三,该方法并不局限于某些特定的系统,而是有着较广的适用范围.因此对于广义Padé逼近方法的研究具有一定的实际意义和理论价值.
磁流变阻尼器减振结构振动台试验与动力可靠性分析  [PDF]
梅真,郭子雄
- , 2017,
Abstract: 为研究随机激励作用时磁流变阻尼器在结构中的实际减振效果以及对结构动力可靠度的影响,开展了随机地震动作用下磁流变阻尼器减振结构振动台试验,并采用等价极值事件原理和概率密度演化方法,对有控和无控模型结构的动力可靠度分别进行了分析.结构控制振动台试验中,采用基于物理随机地震动模型生成的地震动样本作为台面输入.试验及分析结果表明,磁流变阻尼器能够显著降低模型结构层间位移反应的均值和标准差,同时,大多数楼层的绝对加速度反应亦取得了一定的减振效果;随机地震动作用下,模型结构动力响应的变异性显著,并且不同试验地震动样本作为台面输入时,磁流变阻尼器取得的减振效果不同;采用磁流变阻尼器作为减振装置,能够显著提高模型结构各楼层可靠度以及体系可靠度.
In order to investigate the effects of MR dampers on vibration mitigation and dynamic reliability of structures,shaking table tests on the structures with and without MR dampers subjected to random earthquake ground motions were carried out.The reliability assessments of the controlled and uncontrolled structures were respectively performed using the extreme value distribution theory and the probability density evolution method.In the shaking table tests,representative time histories of ground accelerations were generated by employing a physical stochastic ground motion model.Experimental and analytical results reveal that the mean and standard deviation of inter-story drifts of the structure with MR dampers are significantly less than those in the uncontrolled cases,respectively,and the absolute accelerations of most floors are reduced to some extent;the variability in dynamic responses of the controlled and uncontrolled structures subjected to random earthquake ground motions is obvious,and the vibration control effect of MR dampers is significant when the structure is under various ground motions;the seismic reliability of each story as well as the whole structure is evidently enhanced after the installation of MR dampers.
The homotopic solving method of sea-air oscillator for ENSO model
海-气振子ENSO模型的同伦解法

Mo Jia-Qi~,
莫嘉琪
,林万涛,朱 江

物理学报 , 2004,
Abstract: 研究了一个厄尔尼诺 南方海涛 (ENSO)的时滞振子的模型 .利用同伦映射方法求出了ENSO模型的近似解
中频同振柱型矢量水听器及其支撑结构设计
Design of medium frequency co-oscillating cylinder vector hydrophone and its support structure
 [PDF]

刘爽,蓝宇,李琪
- , 2016, DOI: 10.16300/j.cnki.1000-3630.2016.01.017
Abstract: 针对同振型矢量水听器后期悬挂金属弹簧或橡胶绳给使用者带来不便的问题,提出一种中频同振柱型矢量水听器及其支撑结构的设计方案.通过矢量水听器振动系统对其声学特性进行分析,通过ANSYS有限元软件,利用Mooney-Rivlin理论对圆环形橡胶弹簧在压缩情况下的水平剪切刚度进行仿真计算,分析了Rivlin参数对橡胶弹簧剪切刚度的影响,并研制出矢量水听器样机.在1000~4000 Hz频率范围内,对矢量水听器进行了测试,并给出了测试结果.在1 kHz时,声压灵敏度为-195 dB,指向性凹点深度大于20 dB.测试结果表明,此种设计免除了反复悬挂金属弹簧或橡胶绳带来的负面效应.
Due to the inconvenience for users caused by the co-oscillating vector hydrophone using metal spring or rubber cords suspension, a design scheme of medium frequency co-oscillating cylinder vector hydrophone and its supporting structure is proposed. With the vibration system of acoustic vector hydrophone, the acoustic characteristics are analyzed. Using the finite element software ANSYS and the theory of Mooney-Rivlin, the horizontal shear stiffness of circular rubber spring is analyzed in the case of compression. The influence of Rivlin parameter on the horizontal shear stiffness of circular rubber spring is analyzed, and the acoustic vector hydrophone is developed. In 1000~4000 Hz frequency range, the hydrophone is measured, and the result is: the sound pressure sensitivity level is-195dB at 1 kHz and the ration of the maximum to the minimum in the directivity pattern is greater than 20dB. The measurement results show that the design method could reduce the negative influence of repeatedly suspending metal springs or rubber cords.
1000kV淮南—上海输变电工程同塔双回钢管塔风振控制  [PDF]
杨靖波,韩军科,华旭刚,陈政清
中国电机工程学报 , 2010,
Abstract: 以1000kV淮南—上海(皖电东送)输变电工程同塔双回钢管塔为研究对象,对风荷载作用下杆塔的整体振动以及局部钢管杆件的涡激振动的控制措施,分别采用数值仿真和风洞试验进行了研究。针对整塔的风振,提出采用粘弹性阻尼器并联于钢管主材外侧控制弯曲振动、调谐质量阻尼器置于横担端部控制扭转振动的新型联合控制方案;针对局部钢管杆件的横风向涡激振动,提出采用螺旋形扰流线的控制方案;并给出控制装置的关键技术参数的设计方法。控制措施易于工程应用,在一定的参数下,塔顶处顺风向位移和加速度响应可降低30%,杆件横风向振动基本消失,钢管塔的这2类风振得到有效抑制。
风电叶片疲劳加载激振系统解耦控制算法及试验研究  [PDF]
张磊安,魏修亭,陶黎明,隋文涛
- , 2017, DOI: 10.15961/j.jsuese.2017.01.014
Abstract: 中文摘要: 风电叶片逐渐向大型化方向发展,为了提高大型风电叶片疲劳试验的激振能力、缩短测试周期,两激振源联振已成为疲劳测试方法中具有前景的发展方向。首先进行两激振源的耦合特性试验,设计了激振源转速、相位和叶片振幅的测试方案。当2个激振源初始转速设定为35 r/min时,风电叶片在该激振源作用下进行试验,得出2个激振源转速差在±5 r/min范围内波动、相位也存在耦合现象,叶片振幅变化絮乱。为了提高两激振源的同步效果,在分析现有控制策略的基础上,采用并联交叉耦合结构,开发了滑模变结构同步控制算法,并利用李雅普诺夫函数证明了该算法的渐近稳定性。最后,搭建了一套10 MW级大型风电叶片疲劳试验平台,开发了基于分布式网络总线的疲劳激振控制系统,将该滑膜变结构控制算法应用于aeroblade 2.0~54.38风电叶片两点激振试验。试验结果表明,在两激振源转速均为35 r/min时,两激振源的转动步调一致,相位也能基本保持同步,此时叶片振幅最大,且非常稳定。在不同的初始速度驱动下,分别设定为40和30 r/min,2个激振源的转速均能快速跟随并分别保持。由于两者转速不一致,导致叶片振幅发生波动。上述试验结果表明,虽然2个激振源之间的机电耦合是固有存在的,但是设计的滑模变结构控制算法能使2个激振源的转速、相位步调一致,具有良好的鲁棒特性,有效地保证了疲劳试验的顺利进行。
Abstract:The wind turbine blade is gradually developing towards large scale.In order to improve the excitation ability of wind turbine blade fatigue test and shorten the test cycle,the coupling vibration of two exciters has become a promising development direction in fatigue test methods.First of all,the coupling characteristic test of two exciters was carried out,the blade test plan of excitation source speed,phase and amplitude was designed.The wind turbine blade was tested under the effect of this excitation source,in which the two exciters initial speed were set to 35 r/min.The results showed that two excitation speed difference was in the range of ±5 r/min,phase existed coupling phenomenon and the blade amplitude was disorderly.In order to improve the synchronization effect of two exciters,based on the analysis of the existing control strategy,using parallel cross coupled structure,the sliding mode variable structure control algorithm was developed by using the Lyapunov function and the asymptotic stability of the algorithm was proved.Finally,a set of 10 MW large test platform of wind turbine blade fatigue was built,the fatigue excitation control system based on distributed network bus was developed,and the sliding mode variable structure control algorithm was applied to aeroblade 2.0~54.38 wind turbine blade fatigue test,in which test was driven by two exciters.Test results showed that in both the excitation source speed were 35 r/min,the rotational two exciters phase keep step,phase can also basic synchronized,and the blade amplitude was the largest and very stably.Under the different initial speed drive,respectively set as 40 and 30 r/min,the speed of the two exciters can quickly follow and keep respectively.Due to the inconsistency of the two rotational speeds,the amplitude of the blade was fluctuating.The test results showed that although the electromechanical coupling between two exciters was sequestration,the development of the sliding mode variable
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