Leakage source locating of safety valve based on improved KDE algorithm
LI Shuxun1,2, HOU Jianjun1,2, KANG Yunxing1,2, WANG Zhihui1,2
1.School of Petrochemical Technology, Lanzhou University of Technology, Lanzhou 730050, China;
2.Machinery Industry Pump and Special Valve Engineering Research Center, Lanzhou University of Technology, Lanzhou 730050, China
摘要针对难以对安全阀微小泄漏孔进行准确定位的问题，提出了一种基于改进近似核密度估计(kernel density estimation ，KDE)算法的泄漏源定位方法。该算法引入信噪比(signal-to-noise ratio ，SNR)追踪和相关性检测(coherence test ，CT)相结合的方法提取受环境噪声影响较小且泄漏声源能量占优的时频支撑域，使得KDE算法应用于安全阀泄漏源定位的前提成立。在此基础上，通过分频融合处理抑制高频混叠，计算近似核密度函数，消减近似核密度函数三维谱图基底。通过MATLAB软件仿真计算，根据改进KDE谱图峰值得到安全阀泄漏源定位坐标。结果表明，工作压力分别为0.72 MPa，0.75 MPa和0.77 MPa的安全阀泄漏定位结果相对误差都在10%以内，通过声发射测试和改进KDE算法相结合的方法可以较为准确地实现安全阀泄漏源定位，且随着安全阀工作压力的增大，定位精度也相应提高。
Abstract：Aiming at the problem of it being difficult to accurately locate tiny leakage holes of safety valve, a leakage source locating method based on improved approximate kernel density estimation (KDE) algorithm was proposed.With this algorithm, firstly, the combination of signal-to-noise ratio (SNR) tracking and coherence test (CT) was introduced to extract the time-frequency support domain less affected by environmental noise and with dominant leakage sound source energy so that the KDE algorithm could be applied in the safety valve leakage source locating.Then, the high frequency aliasing was suppressed by using the frequency division fusion processing, the approximate kernel density function was calculated, and 3-D spectrogram bases of the approximate kernel density function were reduced.Through simulation computing with the software MATLAB, according to the peak value of the improved KDE spectrogram, locating coordinates of safety valve’s leakage source were obtained.The results showed that relative errors of safety valve leakage locating results under working pressures of 0.72 MPa, 0.75 MPa and 0.77 MPa, respectively are all less than 10%; the method of combining acoustic emission testing and improved KDE algorithm can more accurately locate leakage source of safety valve; with increase in working pressure of safety valve, the locating accuracy increases accordingly.
李树勋1,2，侯建军1,2，康云星1,2，王志辉1,2. 基于改进KDE算法的安全阀泄漏源定位[J]. 振动与冲击, 2021, 40(11): 277-284.
LI Shuxun1,2, HOU Jianjun1,2, KANG Yunxing1,2, WANG Zhihui1,2. Leakage source locating of safety valve based on improved KDE algorithm. JOURNAL OF VIBRATION AND SHOCK, 2021, 40(11): 277-284.
［1］潘伟亮.微启式弹簧载荷安全阀振动特性与气动噪声预测研究［D］.兰州 ：兰州理工大学,2019.
［2］KAEWWAEWNOI W, PRATEEPASEN A, KAEWTRAKULPONG P.Investigation of the relationship between internal fluid leakage through a valve and the acoustic emission generated from the leakage［J］.Measurement, 2010, 43(2):274-282.
［3］JIN Z H, ZHENG X T, TANG L M.Study on spectral characteristics of acoustic emission from pressure pipe leakage［J］.Applied Mechanics & Materials, 2011, 48/49:1182-1185.
［4］MOSTAFAPOUR A, DAVOODI S.Leakage locating in underground high pressure gas pipe by acoustic emission method［J］.Journal of Nondestructive Evaluation, 2013, 32(2) :113-123.
［5］周杨飞.输气管道泄漏连续声发射信号的定位技术研究［J］.现代化工, 2018 ,38(9) :184-187.
ZHOU Yangfei.Location technology for continuous acoustic emission source of gas pipeline leakage［J］.Modern Chemical Industry, 2018, 38(9) :184-187.
［6］李帅永,王鹏飞,严冬,等.气体管道泄漏模态声发射时频定位方法［J］.仪器仪表学报，2016，37(9):2068-2075.
LI Shuaiyong, WANG Pengfei, YAN Dong, et al.Leak location in gas pipelines with time-frequency analysis of modal acoustic emission using smooth pseudo Wigner-Ville distribution［J］.Chinese Journal of Scientific Instrument, 2016, 37(9) :2068-2075.
［7］李振林,张海峰,郝一博,等.天然气管道球阀内漏发声机理及检测试验［J］.振动、测试与诊断, 2017 ,37(3) :525-531.
LI Zhenlin, ZHANG Haifeng, HAO Yibo, et al.Acoustic emission mechanism and testing of leakage in natural gas pipeline ball valve［J］.Journal of Vibration, Measurement and Diagnosis, 2017, 37(3) :525-531.
［8］杨丽丽, 谢昊飞, 李帅永, 等.气体管道泄漏声发射单一非频散模态定位［J］.仪器仪表学报, 2017, 38(4) : 969-976.
YANG Lili, XIE Haofei, LI Shuaiyong, et al.Leak location in gas pipelines by extraction of single non-dispersive mode from leakage-induced acoustic emission signal ［J］.Chinese Journal of Scientific Instrument, 2017, 38(4):969-976.
［9］CUI X W, YAN Y, GUO M, et al.Localization of CO2 leakage from a circular hole on a flat-surface structure using a circular acoustic emission sensor array［J］.Sensors, 2016, 16(11) :1951-1965.
［10］边旭, 张宇, 王佳强,等.基于声传感器阵列的连续泄漏定位方法研究［J］.振动与冲击, 2017, 36(6):134-139.
BIAN Xu, ZHANG Yu, WANG Jiaqiang, et al.Leakage location method based on an ultrasonic sensor array ［J］.Journal of Vibration and Shock, 2017, 36(6) :134-139.
［11］YAN Y, SHEN Y, CUI X W, et al.Localization of multiple leak sources using acoustic emission sensors based on MUSIC algorithm and wavelet packet analysis［J］.IEEE Sensors Journal, 2018, 18(23) :9812-9820.
［12］NESTA F, OMOLOGO M.Generalized state coherence transform for multidimensional TDOA estimation of multiple sources［J］.IEEE Transactions on Audio, Speech, and Language Processing, 2012, 20(1): 246-260.
［13］BRUTTI A, NESTA F.Tracking of multidimensional TDOA for multiple sources with distributed microphone pairs［J］.Computer Speech and Language, 2013, 27(3): 660-682.
［14］WANG L, HON T K, REISS J D, et al.An iterative approach to source counting and localization using two distant microphones［J］.IEEE/ACM Transactions on Audio Speech＆Language Processing, 2016, 24(6): 1079 -1093．
［15］MOHAN S, LOCKWOOD M E, KRAMER M L, et al．Localization of multiple acoustic sources with small arrays using a coherence test［J］.Journal of the Acoustical Society of America, 2008, 123(4): 2136 - 2147．
［16］REDDY V V, KHONG W H, NG B P.Unambiguous speech DOA estimation under spatial aliasing conditions［J］.IEEE/ACM Transactions on Audio Speech & Language Processing, 2014，22(12): 2133-2145.
［17］林伟国, 吴石恩.阀门内漏声波监测及其信号特征提取方法［J］.振动与冲击，2018, 37(9):120-126.
LIN Weiguo, WU Shi’en.Acoustic monitoring and signal feature extraction for valve internal leakage［J］.Journal of Vibration and Shock, 2018, 37(9):120-126.
［18］马浩东，何睿，陈殿京．基于声发射理论的安全阀气体内漏信号特征研究［J］.压力容器,2020， 37(2):24-29．
MA Haodong, HE Rui, CHEN Dianjing.Research on signal characteristics of safety valve leakage based on the acoustic emission technology［J］.Pressure Vessel Technology, 2020, 37(2):24-29.
