| 摘要: |
| 运用表观弹性法，采用二次径向谐振频率计算表现弹性模量，设计高度与直径可比拟，谐振频率不满足压电晶片和金属圆片最低径向谐振频率方程的多维耦合振动复合压电报子。用本方法设计垂直探鱼仪的换能器和提高优质单胞藻饲料多不饱和脂肪酸含量的超声辐射仪换能器。计算结果表明，理论值与实验值相符合。这种方法简单、方便，适用于压电晶片的径向谐振频率低于换能器谐振频率的多维耦合振动复合压电振子的设计。 |
| 关键词: 复合压电振子 多维耦合振动 表观弹性模量 谐振频率 |
| DOI： |
| 分类号: |
| 基金项目:福建省自然科学基金资助项目，C97006号 |
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| DESIGN OF A COMPOSITE PIEZOELECTRIC VIBRATOR WITH MULTIDIMENSIONAL COUPLED VIBRATIONS |
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WANG Qing-chi
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Department Oceanography, Xiamen University, Xiamen, 361005
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| Abstract: |
| If the sizes of the height and the diameter of a composite piezoelectric vibrator are comparable, then the vibrator can be designed using the method of base frequency apparent elasticity when its resonant frequency conforms to the lowest radial resonant frequency equation of the piezoelectric water and metal disc. When the resonant frequency does not conform to that equation, it can be designed with a quadratic radial resonant frequency by the method of apparent elasticity. After the deduction of the piezoelectric wafer axial apparent elasticity module of quadratic resonance wave, Ez=[6.45×1010(8.0145-0.8911f2a2)]/(8.0145-0.5022f2a2), a theoretical curve of the frequency constant (fa) and the radio of height to radius (h/a) of the composite piezoelectric vibrator can be obtained, in combination with the longitudinal vibration frequency equation of the composite piezoelectric vibrator, tg(K1L1/2) tg(K2L2/2)= ρ1c1s1/ρ2c2s2. This method has been used in designing the transducers of vertical fish finder and an ultrasonic radiator applied to studies on the enhancement of the content of multiple-unsaturated fatty acids in qualified single-celled alga fed with ultrasonic radiation techniques. The calculation results show that the theoretical value is consistent with experimental data. The method is simple, convenient and applicable to the design of the composite piezoelectric vibrator with multidimensional coupled vibrations, if the radial resonant frequency of the piezoelectric wafer is lower than the resonant frequency of the transducer. |
| Key words: Composite piezoelectric vibrator, Multidimensional coupled vibrations, Apparent elastic modules, Resonant frequency |
