Structural Analysis and Optimal Design of Mechanical Pendulum of Differential Capacitance Seismometer
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摘要: 地震计可对地震信息进行实时采集与记录,在地震预测和地震灾后监测中发挥了重要作用。本文针对差容式地震计机械摆固有频率高的问题,采用有限元分析软件ANSYS建立机械摆有限元模型,对关键结构十字簧片进行静态和模态分析,并对簧片形状进行拓扑优化设计。采用正弦标定法对优化前后机械摆固有频率进行测量。试验结果表明:优化后实际机械摆固有频率降低了17%,由5.3 Hz降为4.4 Hz,证明了优化设计的可行性。Abstract: Seismometer can collect and record seismic information in real time, which plays an important role in earthquake prediction and post disaster monitoring. Aiming at the problem of high natural frequency of mechanical pendulum of differential capacitance seismometer, the finite element model of mechanical pendulum is established by using ANSYS simulation software. The static and modal analysis of key structure cross spring is carried out, and the shape of spring is topologically optimized. The sine calibration method is used to measure the natural frequency of the mechanical pendulum before and after optimization. The experimental results show that the natural frequency of the actual mechanical pendulum after optimization is reduced by 17%, from 5.3 Hz to 4.4 Hz, which proves the feasibility of the optimization design.
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表 1 机械摆网格划分
Table 1. Mesh generation of mechanical pendulum
零件名称 网格划分方式 单元 单元尺寸/mm 质量块 MultiZone Hexa 2.0 摆动支架 Automatic Default 2.0 十字簧片 MultiZone Hexa 1.0 支撑簧片 MultiZone Hexa 2.0 表 2 材料参数
Table 2. Material parameters
材料名称 弹性模量/GPa 泊松比 密度/ kg·m−3 零件名称 黄铜 100.00 0.35 7 600 质量块 铍青铜 105.14 0.30 8 300 支撑簧片、十字簧片 铝 71.00 0.33 1 050 摆动支架 -
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