Research On Online Removal Technique For Pipelines Containing Liquid Based On Ultrasonic Guided Waves

Industrial pipeline undertakes the task of transporting products,and the fouling is inevitable in the inner wall due to long-term contact with liquid medium.Scaling in industrial pipelines is a common problem in chemical pipelines,petroleum pipelines and heat exchange pipelines,which poses a great threat to the production process and environmental protection.Ultrasonic guided wave fouling removal technology,as a new kind of pipeline fouling removal method,has the advantages of large fouling removal,low waste and no pollution.In order to apply the ultrasonic guided wave technology better to the pipeline cleaning project in the real-world scenarios,the simulation and experimental research on the online fouling removal technology of pipeline containing liquid based on ultrasonic guided wave are carried out in this paper.In this paper,the propagation characteristics of ultrasonic guided wave in the pipe containing liquid,the distribution characteristics of sound pressure leaking into the liquid and the cavitation effect caused by ultrasonic guided wave are analyzed.Secondly,the finite element simulation model of ultrasonic guided wave propagation in the pipe containing liquid was established,and the time domain and frequency domain calculations were carried out on the model respectively,then the transient sound pressure distribution of ultrasonic guided wave propagation along the pipe and the steady distribution of ultrasonic guided wave propagation in the pipe at different frequencies were obtained.The simulation results show:(1)Ultrasonic guided wave attenuates under the influence of water flow in the pipeline.(2)The guided wave sound pressure distribution in the pipeline is different under the excitation of different frequencies.(3)The guided wave sound pressure distribution in the pipeline under the excitation of a single frequency is nonuniform.A fouling removal experiment system based on ultrasonic guided wave was set up in this paper,and pipe descaling experiments were carried out with different water velocity and excitation frequency variables.Experimental results were quantitatively analyzed by energy spectrum analysis.Experimental results show that there is a better descaling performance with water velocity of 0 m/s in pipe,but when the flow velocity is not zero in the pipe,the descaling effect deteriorate due to the attenuation of guided wave sound pressure.Furthermore,the descaling result under different frequency excitation appear differences due to the different sound pressure distribution,and the descaling result is ununiform under single frequency excitation.The online fouling removal technology based on ultrasonic guided wave has potential engineering application value.The study in this paper can provide some references and guidance for the online fouling removal process of pipe containing liquid.