Research On Fouling Biological Protection Technology Of Marine Ranch Based On Ultrasonic Cavitation Effect

Biological fouling in marine pasture aquaculture has always been a serious problem.The infrastructure such as aquaculture cages and buoys are directly exposed to various fouling organisms,and a large number of fouling organisms are easily attached.The attachment of such organisms to offshore ranch cages and other facilities restricts the exchange of water bodies,affects the internal water quality of the cages,reduces the dissolved oxygen content in the water,increases the risk of fish diseases,competes with fish for food and space resources,and causes the sea The structural deformation and fatigue of the pasture breeding cages affect the economic benefits of breeding.Therefore,the protection of fouling organisms in marine pastures is of great significance.At present,domestic and foreign research on anti-fouling devices for marine ranches is still in its infancy.The number of existing foreign products is small,the anti-fouling effect is unknown and the technology is opaque.However,there is no mature anti-fouling device for marine ranches in China,facing my country's marine ranches.With the increasingly serious problem of biofouling,it is very important to carry out research on anti-fouling technology.Aiming at the actual needs of the Bohai Sea Ranch,this article designs a set of special marine ranch prevention technical solutions based on the principle of ultrasonic cavitation,based on the practicality of engineering.This solution can realize real-time anti-pollution of marine ranches,avoid the disadvantages of existing anti-pollution solutions,and has the advantages of high reliability,low economic cost,and wide application range.The main research contents are as follows:First,carry out research on the growth characteristics of fouling organisms in the Bohai Sea.The investigation of the types of fouling organisms in the Bohai Sea,the investigation of the seasonal characteristics of the attachment of fouling organisms in the Bohai Sea,the investigation of the growth law of typical fouling organisms in the Bohai Sea,and the investigation of the distribution of fouling organisms in the Bohai Sea were carried out.Through investigation and analysis,it provides a reference basis for the design of fouling biological protection devices for the Bohai Sea Ranch.Secondly,carry out research on the key characteristics of ultrasonic anti-fouling.The research and analysis have obtained the electromechanical equivalent circuit of the sandwich piezoelectric transducer,which lays the theoretical foundation for the theoretical design of the ultrasonic transducer in the subsequent chapters.At the same time,the Comsol Multiphysics software is used to numerically simulate the distribution of the ultrasonic transducer's radiated sound field in the liquid,and the characteristics of the sound pressure,sound pressure level and sound wave signal directivity of the ultrasonic transducer radiated sound field in the liquid are obtained.This type of ultrasonic transducer has a good sound field distribution.Third,carry out research on the relationship between ultrasonic parameters and marine fouling.Through literature research,the working parameters of the ultrasonic transducer used in the anti-pollution real sea test are obtained.Afterwards,a real-sea test of the ultrasonic transducer to kill fouling organisms was carried out to verify the survey results,and the influence of the frequency and power of the ultrasonic transducer on the killing effect of the fouling organisms was observed,and then the anti-fouling parameters and pollution were obtained through the actual sea test.Damage the relationship between the killing effect of creatures.Finally,the special equipment design for ultrasonic anti-fouling is carried out.Completed the research on special equipment for ultrasonic antifouling and the research on the application scheme of ultrasonic antifouling device for marine ranch.The main work content is the development of ultrasonic generator,including the selection of generator key components,hardware circuit design and software program design.Carry out ultrasonic transducer design research,including transducer shape,material,working frequency,front-to-rear vibration velocity ratio and processing technology;conduct ultrasonic transducer cabin design,including transducer structure design,strength check,and heat dissipation analysis And the watertight performance test,and finally completed the design of the application scheme of the ultrasonic anti-fouling device of the marine ranch,including the design of the communication mode,the design of the installation scheme and the design of the working mode.