基于声学黑洞的拖拉机转向机减振降噪特性实验仿真与参数化分析

Experiment, Simulation and Parametric Analysis of Vibration and Noise Reduction Characteristics of Tractor Steering Gear Based on Acoustic Black Hole

摘要:

拖拉机转向机作为长期与驾驶员身体接触的部件，由其产生和传递的振动噪声会严重影响操作舒适性及效率，甚至危害驾驶员身体健康，采用先进的振动噪声控制技术进行高效减振降噪至关重要。声学黑洞（Acoustic black hole, ABH）是一种前沿减振降噪技术，能有效抑制机电设备振动噪声。针对拖拉机转向机的振动噪声控制问题，本文建立了转向机振动特性高精度数值模型，通过振动特性实验验证了数值模型的准确性，并提出了在转向机外壳中嵌入二维声学黑洞（2D-ABH）板的减振降噪设计方案。利用FEM分析了二维声学黑洞板对转向机关键位置的振动速度抑制和能量聚集效果，结果表明在330 Hz附近能实现最大29.4 dB的减振效果，且在绝大部分频段振动抑制能力良好。为进一步分析声学黑洞关键设计参数的影响规律，分别研究了不同半径、截断厚度、幂指数以及阻尼层厚度、边长等参数下声学黑洞对转向机的振动抑制效果，并得出最优参数组合。采用最优参数组合进行转向机辐射噪声性能仿真分析，结果表明在330 Hz附近转向机辐射噪声下降11.8 dB，且二维声学黑洞板在绝大部分频段对转向机具有良好的降噪效果。

Abstract:

As a component in prolonged physical contact with the driver, the vibration and noise generated and transmitted by the tractor steering gear significantly affect the operational comfort and efficiency, and may even pose a threat to the driver's health. It is crucial to employ advanced vibration and noise control technologies for effective damping and noise reduction. The acoustic black hole (ABH) is a cutting-edge vibration and noise suppression technology that can effectively mitigate vibration and noise in electromechanical devices. To address the vibration and noise control issues in tractor steering gears, a high-precision numerical model of the steering gear's vibration characteristics was established. The accuracy of the numerical model was validated through vibration characteristic experiments, and a vibration and noise reduction design scheme was proposed by embedding a two-dimensional acoustic black hole (2D-ABH) plate into the housing of the steering gear. Subsequently, the finite element method (FEM) was used to analyze the vibration velocity suppression and energy concentration effects of the 2D-ABH plate on key positions of the steering gear. The results showed that a maximum vibration reduction of 29.4 dB was achieved around 330 Hz, with excellent vibration suppression performance observed across most frequency bands. To further investigate the influence of key design parameters of the acoustic black hole, the vibration suppression effects on the steering gear were studied under varying parameters, including radius, truncation thickness, power exponent, damping layer thickness, and side length, and the optimal parameter combination was obtained. Finally, a simulation analysis of the steering gear's radiated noise performance was conducted by using an optimized parameter combination. The results indicated a reduction of 11.8 dB in radiated noise around 330 Hz, and the 2D-ABH plate exhibited effective noise reduction performance for the steering gear across most frequency bands.