Research On Acoustic Source Localization Method On Surface Of Cylindrical Shell Container

The safety of containers has been a concern in recent years.Cylindrical shell containers are the most frequently used and widely used containers in the industry.For example,the tanks for storing chemical liquids and transporting oil and gas are cylindrical container tanks,and the main body of the tank body is mostly a two-dimensional plate structure.In a long-term working environment,containers are prone to material damage due to repeated pressure.Once an explosion occurs,it will cause fire and poisoning.Many large containers are also used as storage bins and reaction bins.If leakage occurs due to material fracture or the protective layer falls off,it will cause economic losses and personal safety problems.Therefore,monitoring these hazardous acoustic emission sources has become an urgent problem to be solved.Non-destructive testing technology is a mature and non-damaging material testing method.Various non-destructive testing technologies are widely used in the manufacture and regular inspection of vessels.Acoustic emission technology is a commonly used method in nondestructive testing and is widely used in vessel health monitoring.With the development of industry and environmental requirements,many container materials are composite materials.The acoustic properties are not known inside the container material.This requires us to consider the anisotropy of the container material.This thesis first briefly describes the development and recent situation of acoustic source localization of two-dimensional anisotropic plates.It summarizes the acoustic source localization methods proposed by other scholars on the two-dimensional plate.On this basis,the acoustic source localization(ASL)technique developed for the two-dimensional planar structures is applied to the surface of cylindrical shell container.The ASL on the cylindrical shell vessel surface is performed by the time difference of arrival(TDOA)method without knowing the acoustic properties of the material.In the experiment six sensors are placed in two clusters.The location of the acoustic source is unknown,and the arrival time of the acoustic signal to each sensor is measured.After analyzing the measured data as discussed in the paper one can calculate the acoustic source position.The experiment is carried out in a more innovative way.The experiment uses a single-channel ultrasonic transceiver system and an oscilloscope to simulate acoustic source localization.By recording and analyzing the signal received by the sensor,the time difference of arrival of the sensor is obtained.Then with the experimental data the program was used to calculate the location of the acoustic source.Secondly,the above sensor placement method for the time difference of arrival method just only is a right angle isosceles triangle.Such placement method has high requirements on operation,and will limit its applications in practical industrial container structure.In this thesis,any triangle time difference method is applied to the surface of cylindrical shell container.This method also uses six sensors to be divided into two groups for measurement.The feasibility of this method is verified by the experimental results.The advantage of this method is that it no longer limits the placement of sensors.Experiments show that this method can also quickly predict the position of the acoustic source,and also has the advantage of the new triangular time difference technology that does not require a large number of calculations and solving nonlinear equations.The experimental results of the two schemes are analyzed separately.The results show that these two methods are not affected by the structural properties of the material,and can quickly and accurately locate the location of the acoustic source.The single channel acoustic emission apparatus was used to simulate the acoustic source positioning experiment.The experimental operation is simple,and the theoretical calculation does not need to solve the nonlinear equations,which greatly reduces the time cost.The experimental results verify that the two method of acoustic source localization can be used to monitor the vessel with a cylindrical shell as the main body,and predict the location of the dangerous acoustic emission source in advance.This method has great potential application value in actual productionapplications.The research results in this thesis provide a theoretical basis and experimental basis for the localization method of the acoustic source on the surface of the cylindrical shell container..