6MF-30便携式风力灭火机气动噪声分析
Aerodynamic noise analysis of 6MF-30 portable pneumatic extinguisher.
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摘要: 便携式风力灭火机是我国用于森林消防的重要设备,然而,其噪声会严重影响操作人员的生理和心理健康。本文采用FLUENT气动噪声场仿真和噪声测试试验相结合的方法,确定风力灭火机的主要气动噪声源,同时提出灭火机降噪优化的设计建议。结果表明:二维模型和大涡模拟(配合FW-H方程)结合的方法可以用于风力灭火机气动噪声的仿真,但在仿真过程中需考虑消声器的影响;风力灭火机主要气动噪声源为叶轮和涡舌,风筒噪声对其总噪声贡献较小;建议增加导流器等,以降低风力灭火机工作过程中操作人员的耳旁噪声。Abstract: Portable pneumatic extinguisher is one of the most important equipment for forest fire-fighting in China. But the noise of portable pneumatic extinguisher may have serious physiological and psychological effects on operators. Simulation via FLUENT and noise test experiment were carried out to determine the position of noise source. In addition, several suggestions about noise reduction of portable pneumatic extinguisher were given. The results indicate that acoustic field could be computed via two-dimensional model when large eddy simulation and Flowcs-Williams/Hawkings equation are used; the muffler should be considered during noise simulation; the main aerodynamic noise sources are impeller and vortex tongue; air duct noise contributing to the total noise is minimal; it is suggested that increasing air director could reduce parotic noise caused by working machine.