A Shaft Seal Diaphragm Structure-based Fiber Bragg Grating Target Flow Sensor

Flow measurement sensors that act as automatic control and the core components of measurement have been widely used in petroleum, chemical and other industries. Doing this work has an important role in ensuring product quality, improving production efficiency and promoting the development of science and technology. At present, the sensor that by measuring the response of the various elastic elements to indirect measurement flow are strain sensor,this kind of sensor has reached a high degree of automation and accuracy,but most use of electric excitation and signal transmission, When the measurement is not only susceptible to electromagnetic interference, and spark discharge caused by fire or explosion, even if useing of explosion-proof treated the existence of the security sensors are also certain risks. Due to the unique electrical insulation gives Fiber Bragg Grating Flow Sensor ability of anti-electromagnetic interference (EMI) and explosive occasions intrinsic safety, based on fiber Bragg grating flow measurement program developed rapidly.Fiber Bragg grating sensor technology obtain stress, temperature, vibration, acceleration and other external parameters through the Bragg wavelength shift. Because its measurement signals and transmit signals is optical signals, it have no electromagnetic interference and the safety characteristics, this can greatly improve the safety and reliability of measurement. Thus,in the field of flow measurement, Fiber Bragg grating sensors have broad application prospects.In this paper, using Fiber Bragg grating as the sensing element, We have studied the flow measurement sensor structure, principles and techniques. The major elements as following:1. Take advantage of the certain functional relation between the target flowmeter force in the target chip and liquid flow rate, we developed a fiber Bragg grating target type flow sensor of diaphragm seal structure. The sensing principle is: wavelength of fiber Bragg grating that paste at Uniform strength cantilever beam has a linear relation with the strain that Cantilever beam suffered; 2. Established the sensing model based on a linear relation between the load capacity of target plate with the Bragg wavelength shift of fiber Bragg grating target type flow sensors;3. According to the specific materials and size of this sensor component I have calculated the theory sensitivity of this sensor. Theoretical sensitivity is 18pm/Kg; the theory resolution is 0.055Kg/pm;4. By weight calibration experiment, obtain the actual sensitivity, loading 16.8pm/Kg, unloading 17pm/Kg. The actual resolution is 0.06Kg/pm;...