基于微穿孔吸声结构的船舶布风器气动噪声降低技术

Aerodynamic Noise Optimization of Marine Air Distributor Based on Microperforation Sound Absorption Structure

针对船用布风器因空间限制静压箱体积小导致布风器消声效果不理想的现象,采用计算流体力学与有限元仿真相结合的方法,对布风器内流道进行优化,减小布风器的流动阻力,降低布风器内产生的湍动能和气动噪声。同时,在布风器两侧湍动能相对较大的侧挡板上微穿孔,结合后面的空腔形成并联的亥姆霍兹共振器用于减小布风器的噪声。结果表明,改进后布风器的阻力损失降低8.27 Pa,侧挡板微穿孔布风器在传递损失上增加4.8d B,监测点最大声压级较原型降低15.1%。该研究可为船用布风器提供新的降噪思路。

In view of the unsatisfactory noise reduction effect of the marine air distributor due to the small volume of static pressure box and space constraints,a method combining computational fluid dynamics and finite element simulation is adopted to optimize the inner flow passage of the air distributor,reduce the flow resistance of the air distributor,and reduce the turbulent kinetic energy and aerodynamic noise generated in the air distributor.At the same time,micro-perforations are made on the side baffles with relatively large turbulent kinetic energy on both sides of the air distributor,and parallel Helmholtz resonators are formed in combination with the rear cavities to reduce the noise of the air distributor.The results show that the resistance loss of the improved air distributor is reduced by 8.27 Pa,the transmission loss of the micro-perforated air distributor with side baffles is increased by 4.8 dB,and the maximum sound pressure level of the monitoring points is reduced by 15.1%compared with that of the prototype.The research can provide a new idea of noise reduction for marine air distributor.