【作者】 吕宏展；

【导师】 梁锡昌；

【作者基本信息】 重庆大学 ， 机械制造及其自动化， 2010， 博士

【摘要】 基于磁触变胶的机磁耦合问题的研究,是一种将电磁流变工质和机械结构相结合的复杂工作。磁触变胶是一种新型的具有流变特性的磁性功能材料,和磁流变液不同,它本身不流动,只有在磁场下受力时才表现出强抵抗变形的机械力学性能。由于其良好的流变特性、物化性能稳定、低能耗、无泄漏、工作无噪声、易控可调。因此,是一种替代磁流变液及磁粉的新工质,联合电磁和机械结构优化设计的器件,可以广泛应用于航空航天、汽车工业、自动控制、医疗康复器械等领域。本文通过对国内外前期相关研究成果的分析,综合考虑磁流变材料工作可靠性、物化稳定性及机磁力学性能,采用化学反应法制备了磁触变胶体,并对其纤维网络结构中化学极性基团对磁粒子的包裹机理进行了表征实验的理论研究及分析。同时,采用自改装试验装置,对磁触变胶在磁场下的电流转矩特性、各剪切速率下的屈服剪应力、粘度剪切速率变化关系进行了试验研究。在对基于磁触变胶体良好磁化性能的基础上,突破磁触变器件传统的阀式、剪切、挤压工作模式,提出一种机磁耦合结构的楔形挤压阻尼增效模型,结合流体力学,对该模型的磁粒子在磁场下的受力及运动行为进行了分析,并将该模型的常用两种工作模式-圆周均布板式工作模式和锥型环工作模式进行了静动力学建模、理论分析及实验仿真。利用机磁耦合的楔形挤压模型对器件进行了动力输出理论分析、创新设计,优化设计。并对磁触变器件励磁线圈空间任意磁场进行了理论计算。同时,对磁触变离合器、磁触变制动器、磁触变减震器进行了详细介绍,并制造出高性能磁触变制动器试验样机。以高性能磁触变制动器为算例,对电磁场和流场耦合下的磁触变胶的流变特性进行了理论分析及数值仿真研究。采用ANSYS电磁通用有限元分析模块对磁触变制动器的磁路优化设计分析及电磁场仿真,同时采用ANSYS Fluent的有限体积法对磁触变胶在磁场下流变状态时的压力场、速度场、动力性能进行了数值计算及分析。在前期试验的基础上,以测试磁触变胶及楔形挤压工作模式的阻尼增效效果为目标,设计并搭建了机磁耦合性能测试试验台,对基于磁触变胶的机磁耦合楔形挤压工作模式的磁触变制动器进行了磁场转矩特性、服役稳定性、磁滞性、热稳定性、滑差功率试验研究和结果分析,并在多台机电传动性能测试试验台上开展了应用实验研究。得出有参考价值的结论,对磁触变器件的进一步研究奠定了坚实的理论基础和试验基础。最后,总结全文,对本文研究的主要贡献和创造点进行了概括总结,并对基于磁触变胶材料的高性能机磁耦合研究进行了展望。更多还原

【Abstract】 The research on coupling magneto-mechanical issue based on magneto-thixotropic gel (MTG) is a complex work combining electromagnetic rheological working medium with mechanical structure. The magneto-thixotropic gel is a new type of magnetic func-tion material with rheology behavior. However, compared with magneto-rheological fluid (MRF), the magneto-thixotropic gel is not able to flow and only when the magnet-ic field is present the strong mechanical properties shown to resist deformation. Mean-while, the magneto-thixotropic gel also chatacterises with better rheology, physical and chemical stability, low power, leak tightness, noiseless, easy to control and adjust. Con-sequently, the magneto-thixotropic gel could be used as a new type of working medium to substitute for MRF, its correlative devices combined electromagnetic with mechanics can be wildly used in such industrial fields as aerospace, automotive, automation, med-ical instruments and so on.By analyzing on previous related research results home and abroad, comprehen-sively considering working reliability, physical and chemical stability, magne-to-mechanical properties, the magneto-thixotropic gel is prepared by chemical reaction method in the dissertation. The theoretical investigation and analysis of characterization experiments were carried out to account for mechanism that chemical polar group in the fiber network structure to enwrap magnetic particles. Meanwhile, when the magnetic field is present, the characteristics such as current-torque characteristic, the shear rate-yield shear stress characteristic and shear rate-viscosity were tested by modified testing equipments.Based on the MTG’s good magnetization property, a coupling magneto-mechanical structure of wedge squeeze damping beneficiated model was proposed, which broke through the traditional working model such as valve model, shear model, squeeze model. Associated with fluid mechanics, the stress and movement behavior of the magnetic particles under the magnetic field were analyzed. Meanwhile, the static dynamic mod-eling, theory analysis and experimental simulation were carried out to the model con-sisting of circular distributed plate working mode and the cone ring working model.The theoretical analysis of power output, creative structure design, optimization design based on the wedge squeeze model was carried out and theoretical calculation on MTG devices was fulfilled aimed to coil magnetic field distribution in the space. Meanwhile, a detail introduction to magneo-thixotropic clutchs, magneo-thixotropic brakes, magneo-thixotropic absorbers were present. At last, a high performance mag-neo-thixotropic brake prototype was manufactured.Take the high performance magneto-thixotropic brake as example, theoretical analysis and numerical simulation on rheology under electromagnetic and flow field were implemented. The magnetic circuit optimization design and electromagnetic si-mulation on magneto-thixotropic brake were done by applied ANSYS electromagnetic module. Meanwhile, aim to calculate the pressure field, velocity field, power perfor-mance of the MTG under the magnetic fields, the theoretical analysis and numerical simulation were carried out by adopting ANSYS Fluent finite volume method.In order to test beneficiated damping efficiency associating MTG with its wedge squeeze working model, a magneto-mechanical coupling performance testing test bench was built, which was used to test magnetic field-torque characteristic, working stability, magnetic hysteresis characteristic, thermal stability, slip power of the magne-to-thixotropic brake. All these experimental tests and application experiments educed some reference value of conclusion which laid a solid theoretical foundation and expe-rimental basis for further study on magneto-thixotropic deveces.Finally, the author summarized the main contribution and creative points in this paper, and had a prospect on the future research on magneto-mechanical coupling issues based on the magneto-thixotropic materials.更多还原