U-shaped pipe blockage state evaluation method based on low-frequency sound pressure signal analysis

• Main Authors: WU LINFENG, ZOU JINHUI, FENG ZAO, FAN YUGANG, WU JIANDE, HUANG GUOYONG, WANG XIAODONG
• Format: Patent
• Language: Chinese; English
• Published: 10.01.2020
• Subjects: DETECTING MASSES OR OBJECTS; GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; MEASURING; PHYSICS; TESTING

The invention discloses a U-shaped pipe blockage state evaluation method based on low-frequency sound pressure signal analysis and belongs to the field of pipeline blockage fault diagnosis. The methodcomprises the steps of acquiring a sound pressure pulse response signal of a U-shaped pipe by using a low-frequency sound pressure signal acquisition device, performing variational modal decomposition on the low-frequency sound pressure signal, determining an optimal modal decomposition number K of the variational modal decomposition according to a component amplitude spectrogram and screening aneffective IMF component through sound pressure level transformation, extracting multi-scale entropy features of the effective IMF component, constructing feature vectors reflecting different degreesof blockage states of the U-shaped pipe, finally applying the feature vectors to continuous hidden Markov model training, and establishing a model capable of evaluating the blockage state of the U-shaped pipe. According to the