针对声全息技术在实际工程应用中的扫描相位误差和有限测量孔径的问题,通过改进测试阵列和算法优化两种途径对其进行分析和解决.使用基于数字麦克风的面阵进行快照法测量,代替了传统的扫描测量,规避了扫描引入的相位误差;从理论上分析了有限孔径下近场声全息重构误差产生机理,并提出了"有限孔径空间扩展+波数域迭代滤波"的声全息算法,选用简谐激励作用下四周为无限大障板的简支钢板为对象,与传统声全息算法结果对比,验证了算法的有效性,并分析了全息面数据空间补零长度和迭代循环次数对声场重构的影响;使用转子台作为被测设备,模拟已知故障,通过单参考源下传感器阵列扫描测量结果验证了算法可以准确地定位模拟故障的空间位置.%Aiming at problem of the scanning phase error and the limited measurement aperture in the practical engineering application,propose two methods to analyze and solve the issues above,which are improved test array and algorithm optimization,using the method of snapshot measurement based on the plane array with digital microphones,instead of the traditional scanning measurement,the phase error is avoided,the limited aperture near-field acoustical holography reconstruction error mechanism are analyzed in theory,A new method of acoustical holography named"limited aperture space extension + wavenumber domain iterative filtering" are proposed. Take a simply-supported infinite steel plate that under harmonic excitation as example,compare with the result from the conventional near-field acoustic holography,demonstrate the effectiveness of the algorithm,analyze on influence of the"0" space range and the number of iterations on the reconstructing of the acoustic field. The rotor testbed is used as the device under test,The known fault is simulated by the rotor table. The applicability of the algorithm is verified by the scanning result of the sensor array with a single reference sensor. The simulation fault location is located accurately.
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