Research On Oil Film Detection Technology On Water Surface Based On Electromagnetic Method

With the rapid development of China's economy,China's offshore oil exploitation and transportation has also been developed rapidly in recent years,and the scale is expanding.The risk of oil spill in offshore oil exploitation,transportation and other processes increases,which has a great impact on the ecological environment,aquaculture,wharf industry and so on.In order to deal with oil spill more effectively and quickly,reduce the impact of oil spill on marine ecological environment and economic losses,it is particularly important to obtain accurate oil spill information in the first time.Detection and acquisition of oil spill information is a technical problem in the process of emergency treatment of oil spill.Especially for the detection of oil film thickness,there is no effective method so far.Based on the propagation law of electromagnetic wave in sea water and the difference of conductivity between good conductor of lossy medium(sea water)and insulator of weak medium(oil),this paper studies the attenuation law of electromagnetic wave amplitude under different conductivity,and designs an electromagnetic wave transmitting and receiving detection device.By detecting and analyzing the received information of electromagnetic wave,the monitoring of oil spill on sea surface and the thickness of oil film can be realized.The measurement work is as follows:(1)Based on the difference of conductivity between seawater and petroleum materials,the differences of electromagnetic wave propagation in liquid materials with different conductivity,such as phase and amplitude attenuation of electric and magnetic fields,are analyzed.According to the above theory,three kinds of media with different conductivity(lossless media such as vacuum,good conductor of lossy media such as seawater and weak dissipative media)are insulated by using MATLAB.The simulation is carried out when the edge is propagating like oil.(2)According to the basic theory of electromagnetic wave propagation in medium,an oil film detection device based on electromagnetic method is designed by Altium designer.The system uses STM32 single-chip computer as the control module of the system to generate AC signals and then transmit them in medium.The received signals are converted into DC signals after rectification.The data are collected by oscilloscope and stored for analysis.(3)The relationship between the distance between the receiving end and the transmitting end of electromagnetic wave and the attenuation of electromagnetic wave is studied.The relationship between oil thickness and the voltage of receiving coil and the relationship between plate spacing and the voltage of receiving coil are obtained by measuring the detection signals at different spacing.Using the Curve Fitting Tool module of MATLAB,the function expression of the voltage value of the receiving coil varying with the coil spacing at different oil thicknesses is obtained.By choosing the best coil spacing,the relationship between the voltage of the receiving coil and the oil thickness is obtained,and the oil film thickness measurement on the sea surface is realized.Based on the propagation law of electromagnetic wave in different media,this paper designs and develops the corresponding electromagnetic wave generating and detecting receiving device,realizes the rapid monitoring of oil film on the sea surface,and chooses the best detection interval to realize the measurement of oil film thickness on the sea surface,thus realizes the extraction of oil film thickness information,improves the emergency disposal ability of oil spill at sea in China,and reduces the marine ecological environment caused by oil spill accidents.Influence.