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目的：液压锥阀产生尖锐刺耳的啸叫噪声，严重地降低了液压锥阀的品质。本文探讨液压锥阀啸叫噪声的产生机理，揭示啸叫噪声对特定频率噪声信号的选择性放大原理，为啸叫噪声抑制提供理论依据。 创新点：观测到介质相变、锥阀开度及阀腔变化下啸叫噪声基频漂移现象，建立空化条件下锥阀流体共振分析模型，获得了锥阀啸叫噪声是对特定频率信号的选择性放大的结论。 方法：1.通过实验分析，观测到液压锥阀中啸叫噪声基频的漂移规律（图5~7、10和11）；2.提出液压锥阀啸叫噪声是流声耦合引起的亥姆霍兹共振假设；3.通过建立锥阀阀腔声学共振频率模型，运用实验与理论相结合的方法分析不同工况下的啸叫噪声基频漂移规律，通过大量实验验证所提假设的正确性（图7、10和11）。 结论：1.液压锥阀流声共振产生啸叫噪声，完成对特定频率噪声信号的选择性放大；2.液压锥阀只有在流体不稳定产生的周期性压力扰动信号的频率与阀腔声学共振频率接近时才产生啸叫噪声；3.运用液压锥阀流声共振产生啸叫噪声的结论，通过改变阀腔声学共振频率，使之与流道内流体不稳定引起的压力扰动频率错开，能有效地抑制液压锥阀中啸叫噪声的产生。“,”The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying “squeal” noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results.