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力矩反馈器 1

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Theoretical study of vibrating effect on heat transfer in laminar flow

Baoxing LI, Maocheng TIAN, Xueli LENG, Zheng ZHANG, Bo JIANG

《能源前沿（英文）》 2010年第4卷第4期页码 542-545 doi: 10.1007/s11708-010-0026-9

摘要： Green’s function method was adopted to study the problem of vibrating effect on heat transfer in laminar flow with constant flux and the influence of Prandtl number and the vibrating frequency on the heat transfer characteristics was investigated. The results show that the variation of the frequency leads to a different distribution of the unsteady velocity and temperature; with a lower frequency, the vibrating will weaken the heat transfer, but the heat transfer will be enhanced with a higher frequency. A lower Prandtl number leads to a strenuous variation of heat transfer.

关键词： vibrating full developed heat transfer

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A method of analysis for modal aero-damping of vibrating blade in incompressible flow

Jun XING, Lin LI,

《能源前沿（英文）》 2009年第3卷第4期页码 465-471 doi: 10.1007/s11708-009-0037-6

摘要： By establishing a research model for aero-damping in a uniform incoming flow, the three-dimension analytical algorithm of the modal aero-damping based on the equivalent viscous damping principle was established. The algorithm, which is suited for low-speed flow, to compute aero-damping is based on classical lift line theory in aerodynamics, according to the analytical solution of unsteady aerodynamic force. According to the analytical equations, the modal aero-damping ratio for different nature frequencies of blades in various fluid field conditions can be solved, and the factors to affect the aero-damping can be determined.The first bend and the first torsion’s modal aero-damping ratios of a compressor blade are calculated by using the above algorithms. The results show that the aero-damping cannot be neglected comparing with the structure damping. It reflects the coupling degree between the flow field and the structure field, so the aero-damping is significant to compute the stress and life of blade.

关键词： compressor different three-dimension analytical classical low-speed

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Achieving desired nodal lines in freely vibrating structures via material-field series-expansion topology

《机械工程前沿（英文）》 2023年第18卷第3期 doi: 10.1007/s11465-023-0758-y

摘要： Accurately controlling the nodal lines of vibrating structures with topology optimization is a highly challenging task. The major difficulties in this type of problem include a large number of design variables, the highly nonlinear and multi-peak characteristics of iteration, and the changeable orders of eigenmodes. In this study, an effective material-field series-expansion (MFSE)-based topology optimization design strategy for precisely controlling nodal lines is proposed. Here, two typical optimization targets are established: (1) minimizing the difference between structural nodal lines and their desired positions, and (2) keeping the position of nodal lines within the specified range while optimizing certain dynamic performance. To solve this complex optimization problem, the structural topology of structures is first represented by a few design variables on the basis of the MFSE model. Then, the problems are effectively solved using a sequence Kriging-based optimization algorithm without requiring design sensitivity analysis. The proposed design strategy inherently circumvents various numerical difficulties and can effectively obtain the desired vibration modes and nodal lines. Numerical examples are provided to validate the proposed topology optimization models and the corresponding solution strategy.

关键词： nodal line topology optimization structural dynamics design material-field series-expansion

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提高地下金属管振动波测试中冲击响应信号的信噪比

韩修廷,王洁春,焦振强,高飞,宋宇波

《中国工程科学》 2005年第7卷第10期页码 64-68

摘要：

提出了在套损振动波检测过程中提高信号信噪比的方法。检测过程中，在井口敲击套管并接收、分析套管的回波，以了解介质的变化情况。由于反射波信号强度较微弱，单纯用一组接收信号无法进行正确的套损分析，采用信号增强方法，即利用多个类似信号进行叠加，增强反射波的有效信号，降低背景噪声，从而得到有用信息，进行正确的套损状况分析。开发了相应的信号处理软件，提高了信号处理速度。通过10井次的测试表明，技术原理可行，软件工作稳定、可靠，便于操作，可以进行多种方法的信号处理，极大地提高了工作效率。

关键词：振动波反射波信号增强信号叠加

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振弦式压力盒在刚性接触面应力监测中的应用研究

陈志坚,游庆仲,林闽,李筱艳

《中国工程科学》 2002年第4卷第12期页码 80-85

摘要：

在阐述振弦式压力盒组成结构和测试原理的基础上，结合江阴大桥(封面)南锚碇基底应力监测实践，分析了振弦式压力盒在刚性接触面应力监测中的可行性和存在的问题，推导出压力盒率定系数的表达式，提出基于有限元模拟分析的压力盒实测资料修正方法，建立了修正系数与被测介质刚度的关系式。研究成果表明，在刚性接触面应力监测中，振弦式压力盒的实测值普遍明显偏小，甚至仅为理论值的十几分之一，其原因是压力盒的实际受力条件与率定受力条件有明确而明显的不同，被测介质刚度对压力盒测值有重要影响。

关键词：压力盒组成结构测试原理误差应力监测修正方法

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硅微z轴谐振陀螺仪负电刚度效应分析及实验验证

夏敦柱,周百令,王寿荣

《中国工程科学》 2007年第9卷第8期页码 66-68

摘要：

介绍了在开环工作状态下硅微z轴谐振陀螺仪由于加工工艺缺陷所导致的误差机理。为减小陀螺仪初始电容差和抑制正交耦合误差，提出了一种闭环控制检测策略。重点分析了其力矩反馈器的电刚度效应并给出其线性数学模型表示式。通过对硅微z轴陀螺仪敏感模态的反馈力与谐振频率的关系分析，间接得出了在敏感方向上电负刚度与力矩器所施电压的内在联系，并在实验上进一步验证电刚度效应。这将为下一步闭环控制方案的设计奠定重要基础。

关键词：硅微z轴陀螺仪负电刚度力矩反馈器微机电系统