Study On Key Technologies Of Ultrasonic Cleaning Of Marine Underwater Monitoring Instruments

In order to fully develop the marine economy,a variety of marine monitoring instruments have been put on the sea in recent years.However,marine biological fouling has seriously interfered with the operation of monitoring instruments.In view of this situation,the previous work has designed an ultrasonic cleaning device for marine underwater monitoring instruments,and conducted preliminary bank experiments at the floating dock.Without limiting power consumption,the feasibility of the ultrasonic cleaning method has been proved.However,the application of limited power supply in the buoy,the ultrasonic cleaning device put forward a strict power limit.In this paper,on the basis of studying the attachment mechanism of fouling biofilm on the surface of plexiglass monitoring instruments,through the combination of numerical simulation and finite element analysis,the working frequency of ultrasonic cleaning and the design of the board sound source are optimized.The optimal design scheme of the ultrasonic cleaning device of plexiglass monitoring instruments under limited power conditions is obtained.? Through the dynamic equation of ultrasonic cavitation bubble motion,the ultrasonic parameters are analyzed the effects of ultrasonic parameters(frequency,amplitude)and environmental factors(surface tension of liquid,pressure of surrounding water)on the movement of ultrasonic cavitation bubbles were analyzed.The study has shown that reducing the frequency of ultrasonic waves,increasing the amplitude of ultrasonic waves,reducing the surface tension of liquids,and reducing the pressure of surrounding water bodies can enhance the effect of ultrasonic cavitation.? The model of marine underwater ultrasonic cleaning system was established by using finite element analysis software.By observing the deformation of the ultrasonic ball on the surface of the water ball,the ultrasonic cleaning process conditions and the vibration plate material were determined.The research shows that when other conditions are the same,the ultrasonic transducer with a frequency of 40 kHz and the vibration plate made of TC4 titanium alloy can achieve the best cleaning effect.? Based on the thin plate bending vibration theory,the vibration frequency equation of the first-order stepped disc under fixed boundary conditions was derived,and a program was written to solve the frequency equation.Based on the solved frequency equation,a first-order stepped disk was designed,and the designed stepped disk was subjected to modal analysis and harmonious response analysis.? The vibration model of the board acoustic source for ocean underwater ultrasonic cleaning was established.The existing ultrasonic mechanical vibration system was subjected to finite element analysis and structural optimization.The disc surface amplitude and underwater sound field of the two structures were compared.At the same time,the finite element optimization analysis method was applied to the vibration analysis of ultrasonic plate sound source.Analyzed the influence of the transducer array method on the vibration characteristics of the board sound source,compared the vibration distribution of the board sound source at the same frequency and different transducer array methods,and obtained a reasonable array method to achieve a better cleaning effect.? An experimental platform for underwater ultrasonic cleaning device was designed.The influence of different working methods of ultrasonic cleaning on the effect of ultrasonic removal was studied by scanning electron microscope,and the actual sea experiment of ultrasonic cleaning device was carried out.The research proves that the optimized ultrasonic cleaning device applied on the buoy can effectively prevent the biological attachment of marine underwater monitoring instruments,and when the total time of ultrasonic action is the same,the shorter the ultrasonic interval time,the more significant the effect of ultrasonic decontamination.