Optimization Of Acoustic Window Of Sonar Logging Instrument

With the increasing global demand for energy and the need for energy reserves,it is of great significance to use underground cavern to store oil or natural gas energy.At present,most underground energy storage is salt cavern underground gas storage.In order to ensure the safe and stable operation of salt cavern gas storage,it is necessary to detect the internal form of gas storage.The most commonly used detection method for salt cavern gas storage is based on ultrasonic detection.In ultrasonic detection equipment,the most core component is ultrasonic transducer used for transmitting and receiving acoustic signals.Therefore,it is very important to select appropriate ultrasonic transducer energy and add protective measures to its exterior in ultrasonic detection equipment.Therefore,this paper takes the design of the acoustic window of ultrasonic detection equipment for salt cavern as the research object,and studies the optimal detection frequency of salt cavern gas storage,the acoustic properties of different materials and the acoustic properties of the acoustic Windows with different structures.The main work of this paper is as follows:Starting from the analysis of the internal environment of salt cavern gas storage,the existing ultrasonic attenuation calculation method in salt cavern gas storage is analyzed.According to the construction method of sonar equation and attenuation calculation formula,the effective frequency equation suitable for salt cavern gas storage detection is established.A suitable frequency of 20 k Hz is selected by combining this method with the ultrasonic beam directivity calculation.The finite element method was used to establish the acoustic performance analysis model suitable for the acoustic window,and the density,Young’s modulus and Poisson’s ratio of three material parameters affecting the acoustic window performance were analyzed in detail,so as to provide the best parameter selection of the acoustic window material.Finally,organic glass,aluminum and titanium alloy were selected as the sound window materials for salt cavern ultrasonic detection equipment according to the number of common sound transmission materials combined with the best parameters.The structure of the acoustic window of ultrasonic detection equipment is designed,and the single-layer structure,double-layer fit structure,double-layer spacer structure and threelayer composite structure are proposed.On this basis,according to the above selected plexiglass,aluminum and titanium alloy three materials in different structure combination,and the combination of the acoustic window by changing the thickness ratio of different materials,strength analysis;Under the condition that the strength of the material is satisfied,the influence of the thickness ratio of different materials on the sound transmission performance is explored,so as to select the structure with the best sound transmission performance under the condition of strength.Through comparative analysis,the double-layer 7mm aluminum plate with 9mm water layer between it has the best sound transmission performance,which provides guidance for the design and optimization of subsequent sonar detection equipment.