摘要
基于近场声全息(NAH)技术及空间快速傅里叶变换(FFT)算法,利用虚拟仪器软件Labview开发了柴油机噪声测试与分析系统;对系统中的数据采集模块、NAH模块、仿真程式模块进行了分析;通过已知声源进行仿真模型校正,该系统具有对噪声进行频域分析及识别的功能。该文以直列四缸涡轮增压柴油机为测试对象,在次推力侧主要对1800r/min、3000r/min两转速工况进行了测试及声压级分析;对主推力侧、发动机前端寻找最大声压级。结果表明:系统仿真时能准确识别已知声源信号;1800r/min工况下,噪声幅值较大区域主要有:油底壳、带轮端、发电机与带轮端相接处等。3000r/min工况下,在气缸盖罩、带轮端、下缸体等位置产生了较大噪声;主推力侧、发动机前端都在高转速3600r/min,1410-2820Hz频段内出现最大声压级。
Based on near-field acoustical holography(NAH)technology and space fast Fourier transform(FFT)algorithm,a noise measurement and analysis system for diesel engine was developed using virtual instrument software Labview.The block diagrams of data acquisition module,NAH module,and simulation program module in the system were analyzed.Calibrated by the sampling data of a known sound source,the system can be used to analyze and identify frequency domain of the noise.Taking a in-line four-cylinder turbocharged diesel engine as the test object,the sub-thrust side working conditions of the 1800 r/min and 3000 r/min were tested and corresponding sound pressure level.The maximum sound pressure levels of the main thrust side and the engine front were studied.The results show that the system can accurately identify the known sound source signals during the system simulation.In the 1800 r/min operating conditions,the areas with large noise amplitude mainly include:oil pan,pulley end,the joint between generator and pulley end,etc.Under 3000 r/min operating conditions,large noise is generated in the cylinder head cover,pulley end,lower cylinder,etc.;the main thrust side and the engine front end reach maximum sound pressure in the frequency range of 1410-2820 Hz at high speeds of 3600 r/min.
作者
吴彪
申立中
毕玉华
彭国材
WU Biao;SHEN Li-zhong;BI Yu-hua;PENG Guo-cai(Yunnan Key Laboratory of ICE,Kunming University of Science and Technology,Yunnan Kunming650500,China)
出处
《机械设计与制造》
北大核心
2021年第1期67-71,76,共6页
Machinery Design & Manufacture
关键词
柴油机
声压级
虚拟仪器
声源识别
近场声全息技术
Diesel Engine
Sound Pressure Level
Virtual Instrument
Sound Source Identification
Near Field Acoustic Holography
