Effect of Transducer Array Distribution on Pipe-Fouling Removal Process Based on Ultrasonic Guided Waves

Abstract Pipes are inevitably fouled due to the long-term transport of liquid materials, which cause pipe blockages, leaks and corrosion. Ultrasonic guided waves (UGWs) generated by transducers can induce cavitation within pipes, thereby removing scale deposits from the inner walls (descaling). Cavitation is influenced by sound pressure, and the distribution of ultrasonic transducers affects the sound pressure within the pipes. This study employed the finite element method and fluid-solid coupling knowledge to explore the influence of different transducer distributions on the descaling effect. The UGWs-based environmentally friendly pipe fouling descaling method can achieve efficient online descaling without removing the pipe. In this study, the resonance frequency corresponding to each different scheme was selected as the excitation frequency. The fouling duration and descaling duration of the experiment were 144 h and 30 min, respectively. In the experiment, the descaling efficacy was semiquantitatively evaluated by examining the calcium content in the pipes using energy dispersive spectroscopy (EDS) analysis. The results showed that the average EDS-based calcium reduction indexes of the three transducer distribution schemes were 82.69%, 81.41%, and 76.63%, respectively. Among these, the scheme with transducers uniformly distributed around the circumference of pipe demonstrated the most effective descaling performance.