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《中国惯性技术学报》2015,(5)
光纤陀螺在应用环境确定的振动条件下保持输出精度是光纤陀螺工程化的必然要求,结构材料的选择直接影响输出精度。从陀螺结构的振动性能理论分析出发,将铍铝合金材料应用在轻小型光纤陀螺的关键结构设计中,通过建立有限元模型并仿真铍铝合金结构陀螺的振动性能,陀螺可满足谐振点大于2 k Hz的要求。加工、装配了铍铝结构实验样机(精度要求0.1(°)/h)并进行了多次10 Hz~2 k Hz正弦扫频振动实验。扫频过程中振动传感器未检测到结构的谐振,陀螺输出零位偏置变化0.04(°)/h,噪声水平与振动前后相当。结果表明铍铝合金材料优良的特性满足轻小型光纤陀螺振动性能要求,在严格重量约束下能降低结构设计难度,符合航空航天领域对惯性仪表质量苛刻的要求。 相似文献
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弹性支承滑动轴承—转子系统稳定性的研究 总被引:3,自引:2,他引:3
本文研究弹性支承滑动轴承-转子系统的动力稳定性问题,建立了弹性支承滑动轴承-Jeffcott转子系统的力学模型,采用牛顿延拓法从理论上对该转子轴承系统的动力稳定性进行了分析,讨论弹性支承的刚度对系统稳定的影响,从而提出提高系统稳定性的有关措施。最后,依据理论分析,利用Jeffcott转子实验台,作者设计和加工了一副弹性支承器,通过刚性支承和弹性支承两个对比实验,对理论分析的结果进行了验证。实验结果 相似文献
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本文对高速压气机转子提出了一个多平面的低速动平衡方法,其中通过误差分析可以指导校正面的选择及平衡的工艺过程。经实践验证,这个方法是可行,能使转子高速运转平稳。 相似文献
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本文建立了一种预测空心材料导热性的方法。研究了空心材料的导热性。用柱形空心材料分析了体分比和孔洞的排列方式对整体材料导热性的影响,用圆柱形、方柱形空心材料和含裂纹材料,分析了空心形状对材料导热性的影响。同他人的实验结果和某些现有的理论模型比较表明,本文方法是有效的。本文的结果能够很好地解释实验结果。 相似文献
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空心材料导热性能预测研究 总被引:2,自引:0,他引:2
本文建立了一种预测空心材料导热性的方法。研究了空习材料的导热性。用柱形空心材料分析了体分比和孔洞的排列方式对整体材料导热性的影响,用圆柱形,方柱形空心材料和含裂纹材料,分析了空心形状对材料导热性的影响。同他人的实验结果和某些现有的理论模型比较表明,本文方法是有效的。本文的结果很好地解释实验结果。 相似文献
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介绍螺桨转子系统颤振涡动的一种算法。本算法考察桨叶的振动变形,桨轴-支承系统的振动特性,以及螺转子的不平衡力。利用本算法对一模型螺桨转子和一实际螺桨转子进行了分析计算,对螺桨转子轴头动刚度、浆叶弹性变形、桨盘不平衡度等因素对螺桨转子系统颤振涡动的影响进行了分析,表明螺桨转子轴头动刚度下降时,螺浆发生颤振涡动的极限飞行速度下降。模型螺桨转子的计算结果与风洞试验结果相当吻合,证明本算法是正确的。 相似文献
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提出一种采用转子赤道刻线,利用赤道光电传感器的输出来控制阻尼力矩方向的半球施矩主动阻尼控制方案。在气浮装置上用大球转子进行了模拟试验。试验表明该主动阻尼控制方案可在大范围内对转子进行阻尼,大大减少了阻尼时间。中对大球转子及实心转子主动阻尼结果进行了对比分析,表明对于实心转子ESG,赤道刻线主动阻尼方案能将阻尼时间减少到被动阻尼的10%。 相似文献
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Effects of material properties on the total stored energy of a hybrid flywheel rotor 总被引:4,自引:0,他引:4
Summary A numerical method based on the assumption of a generalized plane strain (GPS) state is presented for calculating the stress
and strength ratio distributions of the rotating composite flywheel rotor of varying material properties in the radial direction.
The rotor is divided into many rings and each ring has constant material properties. All the rings are assumed to expand and
have the same axial strain. A three-dimensional finite element method is then used to verify the accuracy of the present method.
This method gives a better solution for most of the rotors than other methods of a plane stress or plane strain state. After
verification, the effects of material properties on the total stored energy (TSE) of the composite flywheel rotor are investigated.
For this purpose, the material properties of the rotor, i.e. circumferential and radial Young's moduli, ply angles and mass
densities are expressed by power functions of the radius, and the rotor is analyzed. The analysis shows that TSE can be most
effectively increased by changing the circumferential Young's moduli along the radius, which amounts to over 300% of TSE of
the constant material properties. The variation of ply angles along the radius can increase TSE by about 30% at most. The
method of changing the mass densities along the radius could be also effective but its effects are not so noticeable in the
rotor where the circumferential stiffness is properly arranged.
Received 7 June 1999; accepted for publication 15 January 2000 相似文献
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A theoretical method for analyzing the axisymmetric plane strain elastodynamic problem of a non-homogeneous orthotropic hollow
cylinder is developed. Firstly, a new dependent variable is introduced to rewrite the governing equation, the boundary conditions
and the initial conditions. Secondly, a special function is introduced to transform the inhomogeneous boundary conditions
to homogeneous ones. By virtue of the orthogonal expansion technique, the equation with respect to the time variable is derived,
of which the solution can be obtained. The displacement solution is finally obtained, which can be degenerated in a rather
straightforward way into the solution for a homogeneous orthotropic hollow cylinder and isotropic solid cylinder as well as
that for a non-homogeneous isotropic hollow cylinder. Using the present method, integral transform can be avoided and it can
be used for hollow cylinders with arbitrary thickness and subjected to arbitrary dynamic loads. Numerical results are presented
for a non-homogeneous orthotropic hollow cylinder subjected to dynamic internal pressure.
The project supported by the National Natural Science Foundation of China (10172075 and 10002016) 相似文献
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In the paper, two theoretical poroelastic osteon models are presented to compare their poroelastic behaviors, one is the hollow osteon model (Haversian fluid is neglected) and the other is the osteon model with Haversian fluid considered. They both have the same two types of impermeable exterior boundary conditions, one is elastic restraint and the other is displacement constrained, which can be used for analyzing other experiments performed on similarly shaped poroelastic specimens. The obtained analytical pressure and velocity solutions demonstrate the effects of the loading factors and the material parameters, which may have a significant stimulus to the mechanotransduction of bone remodeling signals. Model comparisons indicate: (1) The Haversian fluid can enhance the whole osteonal fluid pressure and velocity fields. (2) In the hollow model, the key loading factor governing the poroelastic behavior of the osteon is strain rate, while in the model with Haversian fluid considered, the strain rate governs only the velocity. (3) The pressure amplitude is proportional to the loading frequency in the hollow model, while in the model with Haversian fluid considered, the loading frequency has little effect on the pressure amplitude. 相似文献
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针对磁悬浮挠性转子的纯有限元分析模型精度低的问题,提出一种磁悬浮挠性转子系统模型复合辨识方法。该方法首先采用有限元方法把磁悬浮挠性转子划分为多个Timoshenko梁单元,建立磁悬浮挠性转子系统模型,并对其挠性临界频率、阻尼、刚度和振型等关键参数进行分析,进而得到磁悬浮挠性转子的等效降阶数学模型;然后采用鲁棒自适应方法分析磁悬浮挠性转子系统的动态特性;最后,采用变LEVY方法从动态特性分析数据中对磁悬浮挠性转子进行系统辨识,校正有限元分析得到的降阶数学模型。实验结果表明,本方法可以得到磁悬浮挠性转子较为准确的系统模型。 相似文献
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I. D. Rogozin 《Journal of Applied Mechanics and Technical Physics》1975,16(2):243-247
A hollow sphere of an elastic binding material of slight stiffness, bonded randomly by “fiber” segments of a stiffer material, is considered. Polymer material, for example, can be the binder. Such a bonding permits obtaining a material with improved properties, where the material on the whole is quasi-isotropic [1]. The stress distribution in a hollow sphere is obtained. 相似文献
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超声马达转子摩擦材料磨损特性研究 总被引:8,自引:2,他引:6
利用MPX-200型销-盘摩擦磨损试验机和自制的超声马达摩擦特性模拟试验台,考察了摩擦材料在普通滑动试验和超声马达试验条件下的磨损性能,研究了接触预压紧力和负载力矩对转子摩擦材料磨损状态的影响,并借助于扫描电子显微镜和光学显微镜对摩擦材料磨损机理进行分析,指出可用绝对转差率Sf描述超声马达定子和转子相对滑动摩擦磨损程度。结果表明,摩擦材料在超声马达试验条件下的磨损状态与普通滑动试验条件下的不同,普通滑动试验时摩擦材料磨损表面形成了层状覆盖膜,而超声马达转子摩擦材料磨损表面无覆盖膜,其表面呈现犁沟磨损和疲劳剥层磨损特征,这种磨损特征随预压紧力和负载力矩变化而变化,与绝对转差率Sf有关,且存在2个临界转变区。 相似文献
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We find families of finite deformations of a Cosserat elastic continuum on which the system of equilibrium equations is reduced
to a system of ordinary differential equations. These families can be used to describe the expansion, tension, and torsion
of a hollow circular cylinder, cylindrical bending of a rectangular slab, straightening of a circular arch, reversing of a
cylindrical tube, formation of screw and wedge dislocations in a hollow cylinder, and other types of deformations. In the
case of a physically nonlinear material model, the above-listed families of deformations can be used to construct exact solutions
of several problems of strong bending of micropolar bodies. 相似文献
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超声马达转子摩擦材料厚度对驱动性能的影响研究 总被引:5,自引:0,他引:5
制备了一系列不同厚度的摩擦材料 ,利用超声马达摩擦特性模拟试验装置 ,研究了摩擦材料厚度对超声马达空载转速和堵转力矩的影响 .基于一个简化的行波超声马达定子和转子接触模型 ,用有限元法计算了定子和转子接触变形随摩擦材料厚度的变化规律 ,提出了定子和转子具有合理接触变形的摩擦材料厚度范围 .根据试验和理论计算结果确定了摩擦材料最佳厚度 ,为超声马达摩擦材料厚度设计提供了理论依据 相似文献
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Radial inflation–compaction and radial oscillation solutions are presented for hollow spheres of isotropic elastic material
that are radially inextensible. The solutions for radial inflation–compaction and radial oscillation are obtained also for
everted radially inextensible hollow spheres of isotropic elastic material. The static and dynamic results for everted and
uneverted radially inextensible hollow spheres are then compared. Harmonic and compressible Varga materials are used to demonstrate
the solutions.
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