共查询到20条相似文献,搜索用时 15 毫秒
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现有的商用磁流变仪不能满足磁流变胶泥高剪切率和高剪切应力测试的要求,对比设计了密闭圆筒剪切模式的磁流变胶泥流变特性测试装置。在完成总体结构设计的基础上,建立了剪切通道励磁磁路的分析模型,得出了剪切通道磁场强度与励磁电流的关系,并进行了有限元仿真验证。考虑转子与外筒存在倾斜,建立了磁流变胶泥转矩传递的力学模型,得到了转子与外筒倾斜角度与传递转矩误差的理论关系。完成了测量装置样机的制作,开展了磁流变胶泥流变学特性测试,在低剪切率下测量装置测试结果与安东帕流变仪测试结果能较好吻合。研究表明,测试装置能够实现25 000 s-1的高剪切率和200 k Pa的高剪切应力测试。 相似文献
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研究不同材料配比下的热损功耗和可调刚度的复杂关系,对提升叠层型磁流变支座(MRB)的隔减振性能具有重要意义。基于力磁耦合理论,构造分析支座的宏微观力磁耦合模型,进而计算支座磁场分布和水平剪切刚度,并考虑热损功耗的影响,得出支座刚度变化与磁流变橡胶(MRR)颗粒体积比的关系。通过MTS测试机对支座进行剪切测试,所得实验数据与理论计算的结果进行对比分析。结果表明,该支座最大可承受的热损功耗限制在38. 7 W时,支座剪切刚度变化为最大且可达42. 8%,其最优颗粒体积比为12%,且最优颗粒体积比随热损功耗的变化而发生偏移。该宏微观模型寻找到支座热损功耗与剪切刚度变化率的一种平衡规律,为磁流变橡胶支座进行结构和性能的优化设计提供了新思路。 相似文献
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Dynamic modeling and analysis of drum-type washing machine 总被引:1,自引:0,他引:1
Hee-Tae Lim Weui-Bong Jeong Keun-Joo Kim 《International Journal of Precision Engineering and Manufacturing》2010,11(3):407-417
In this study, dynamic analysis of a drum-type washing machine has been conducted using a simplified dynamic model considering
gyroscopic effects. Its mathematical model has 6-degree of freedom in the complex coordinate space into which is transformed
real coordinate space to understand the whirling motion easily. Dynamic analysis is performed using MATLAB. For the purpose
of numerical verification, the results for unbalance response are presented and compared with the experimental vibration test.
The mathematical model proves quite good accuracy in predicting dynamic characteristics which could be changed by the parameters
of design variable and can reduce design cycle shortly. Dynamic characteristics of a washing machine are shown through shape
and directivity index (SDI), whirling orbits, rigid and flexible mode of a drum type washing machine during drum run-up. In
designing drum type of washing machine, it is efficient than finite element method to analyze behaviors of drum and tub. 相似文献
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新型盾构机刀盘设计与有限元分析 总被引:2,自引:0,他引:2
为满足盾构机在复合型地层下掘进的需要,设计了一种新盾构机刀盘。刀盘主要由刀盘框架、滚刀、刮刀和泡沫管组成,可替代进口刀盘或可与其他进口装置组合使用。运用有限元软件对该刀盘在实际工况下的受力情况进行了分析,结果表明,刀盘能够满足实际工作要求,结构可靠性高。 相似文献
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A new model of a linear magnetic actuator (LMA) that can be applied to the controllable squeeze film damper (CSFD) was proposed,
designed, and fabricated. To validate the operation of the proposed actuator, a mathematical model of the proposed LMA was
derived through experiments. From the experimental results it was verified that the electromagnetic force depends upon the
position of the mover (the outer damper ring of the CSFD) and the applied current. Also, the electromagnetic force varies
symmetrically with the position of the mover within the working region. A self-tuning fuzzy PID controller was applied to
control the position of the novel LMA. Further, the proposed LMA was assembled in the squeeze film damper (SFD), where the
clearance can be controlled by LMA. To investigate the damping effect of the damper under various clearances by controlling
the LMA, experiments on the rotor test-rig were conducted. From the experimental results, the proposed device, which is composed
of SFD and LMA, was verified to be very effective for attenuation of the vibration of the rotor system.
This paper was recommended for publication in revised form by Associate Editor Dong Hwan Kim
Kyoung Kwan Ahn received the B.S. degree in the department of Mechanical Engineering from Seoul National University in 1990, the M. Sc. degree
in Mechanical Engineering from Korea Advanced Institute of Science and Technology (KAIST) in 1992 and the Ph.D. degree with
the title “A study on the automation of out-door tasks using 2 link electro-hydraulic manipulator” from Tokyo Institute of
Technology in 1999. He is currently a Professor in the School of Mechanical and Automotive Engineering, University of Ulsan,
Ulsan, Korea. His research interests are design and control of smart actuator using smart material, fluid power control and
active damping control. He is a Member of IEEE, ASME, SICE, RSJ, JSME, KSME, KSPE, KSAE, KFPS, and JFPS.
Truong Quoc Thanh received the B.S degree in the department of Mechanical Engineering from Hochiminh City University of Technology in 1998,
and the M.Sc. degree with title “Dynamic stiffness method in calculation vibration of structure” from the master program of
mechanics under Inter-University Cooperation Program between Liege University (Belgium) and HCMUT (Vietnam) in 2000. From
2000 to 2004, he worked as a lecturer in the mechanical department of Hochiminh City University of Technology. His teaching
subjects are relevant in Advanced Manufacturing Methods, Measuring Technique and Manufacturing Technique. He is currently
a Ph.D. candidate at the University of Ulsan. His research interests focus on designing and manufacturing of new actuators,
vibration control theory and application theories. 相似文献
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为磨削后被乳化油和金属颗粒污染的零件 ,设计一种应用涡流搅动和超声波的预清洗设备 ,选用对环境友好的水基清洗剂。撇油和过滤设计使清洗液能长时间循环使用 ,节约水资源和化学品 ,降低清洗工序成本。 相似文献
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非牛顿流体在管道输送时其流变特性是管道工艺设计的主要依据.基于管流法的流变测试原理,分析已有浓密膏体流变特性测试实验台优缺点,取长补短对其实施改进.采用液压系统代替气压方式推送物料实现管道输送,以"稳流量测压差"代替"定压力测流量"的方式获取关键参数,以此推算浓密膏体的流变特性,为浓密膏体的管道输送工艺设计提供新实验平台.以赤泥为例进行实验验证,确定了67.5%~68.5%浓度赤泥不同管径输送下的流变模型.测量过程表明本实验台可行且操作方便、数据可靠;原始实验数据及其处理结果符合理论规律. 相似文献
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传统被动支座受自身材料和结构性能限制,无法通过调节结构参数来抵抗大冲击振动力的破坏,其抗冲与耗能能力有限。将模量、阻尼损耗因子可调的磁敏弹性体引入到支座结构设计中,从抗冲防振的力学性能需求出发,兼顾考虑其机械和磁学性能,基于相似理论提出了剪切模式下的小尺度磁敏弹性体支座结构设计方法,利用Maxwell有限元软件对其磁路进行仿真优化,根据理论公式计算了刚度,并加工出小尺度支座样机,通过MTS测试机对其性能进行测试。结果表明,在外加可控激励电流条件下,磁敏弹性体支座的最大横向刚度和最大横向阻尼分别增加了43.9%、77.5%,理论刚度值与试验刚度值吻合较好,可望按该方法设计出支座来提高结构系统的抗冲隔振和耗能能力。 相似文献
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Sujuan Jiao Yu Wang Lei Zhang Hongxing Hua 《Mechanical Systems and Signal Processing》2010,24(5):1570-1578
A hydraulic damper is developed to generate the shock wave in this paper. The working principle of the damper is explained and the corresponding mathematical model is established. The shock wave characteristics under different shock velocities are obtained by using the numerical computation and experiment. The results show that the shock wave characteristics directly relate to the sectional area of the exhausted passages. The computational results agree well with the experimental data, which means that the proposed mathematical model can be used for the engineering design. 相似文献
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针对旋转式磁流变液阻尼的磁滞性问题以及由于磁滞性而造成的旋转式磁流变液阻尼器输出力矩不稳定的问题,设计了一种差动式阻尼器,不仅可以使输出的力矩可控性更好,而且有效地克服了磁滞现象的影响.在通过理论计算得到磁流变液差动阻尼器输出力矩模型的基础上,利用ANSYS有限元分析软件对磁流变液差动阻尼器进行了磁场分析,得到了磁流变液的磁感强度与磁流变液差动阻尼器线圈中的控制电流之间的关系,结合数值分析软件得到了磁流变液差动阻尼器的输出力矩与线圈中的控制电流之间的关系.研究结果表明,通过控制磁流变液差动阻尼器的控制电流可以实时调整差动阻尼器的输出力矩大小及方向,对磁流变液阻尼器作为精确控制的力矩控制元件奠定了理论基础. 相似文献