Reaserch On Sea Overflow Petroleim Detection Method Based On Long Period Fiber Grating

In recent years, ocean is polluted more and more serious by petroleum pollutant. Therefore the development of a real-time, rapid, accurate water petroleum pollution detection method has important practical significance. Due to the high sensitivity of external environment changes, Long period fiber grating is widely used, This paper based on the refractive index sensitive of long period fiber grating, proposed the method of using long period fiber grating for sea water petroleum pollutants detection, different kind and different concentrations of petroleum pollutants were analyzed, the influence of temperature to the sense results is analyzed. Then, a quasi-distributed petroleum pollutant detection system based on long period fiber grating is set up. The main contents include:Firstly, introduces the research progress on petroleum pollutant detection method and long period fiber grating based on the coupled mode theory, the long period fiber grating refractive index sensing features is analyzed, these provide theoretical basis for follow-up experimental study.Secondly, a single long period fiber grating is used for detecting whether petroleum pollutants are in sea water, and use single long-period fiber grating detect different concentrations of petroleum pollutants in solution,the relationship between petroleum pollutants and long period fiber grating resonance wavelength is analyzed。Then, through theoretical and experimental research, we get the influence of temperature on the result of long period fiber grating sensor measurement, and on the basis of that, we series a reference grating which temperature characteristic is known to reduce the influence of temperature on the sensing results.Finally, A quasi-distributed petroleum pollutant detection device based on long period fiber grating is set up, and weather gasoline is in water is studied as a case.