مقاله انگلیسی رایگان در مورد مطالعه اندازه جریان paste مبتنی بر فیبر نوری – امرالد 2017

The main methods available for measuring slurry flow are: (1) the differential pressure method; (2) the electromagnetic method; (3) the Doppler ultrasonic method; (4) the volume method; and (5) the Coriolis mass method. A differential pressure flow meter (1) can be used for measuring the flow rate of various slurry fluids. The Venturi tube is generally used to ensure that the throttle device does not deposit solid particles. It is important to take care to avoid abrasion and issues with paste material jamming. The electromagnetic method (2) can measure pulp, coal slurry, slurry and other high-conductivity liquids, but this sensor cannot be installed in a horizontal pipe. The Doppler ultrasonic method (3) may introduce large measurement errors because of the heavier flow on the bottom of the tube. The volume method (4) is the most traditional measurement approach, but its efficiency is considered to be too low. The Coriolis mass method (5) can be used to measure the flow of liquid containing a small amount of solid particles; however, when the quantity of solids increases, and the solid particles are large, then the issue of anti-blocking must be considered(Wang and Zhang, 2014; Wang et al., 2015; Binzoni and Martelli, 2015; Andrzej et al., 2015; Tajima et al., 2014). Paste filling is an important method for mine filling, and flow measurement is, therefore, the first problem to be solved. Optical fiber sensing technology is introduced into the flow measurement to provide improved accuracy and stability. Optical properties such as intensity, phase, and frequency of the light transmitted in the optical fiber are controlled, and appropriate optical detection methods can then convert it into electrical signals. The resulting flow measurement instrument is highly complex and both the flow meter measurement principles and the measurement method have their advantages and disadvantages. Optical fiber Doppler sensors have rapidly developed in recent years to measure flow with high precision, fast dynamic response, good space differentiating ability as well as many other advantages. Consequently, it is becoming one of the main methods of flow measurement. Based on the scattering principle, the laser Doppler and the optical mixing principle, an optical fiber Doppler sensing system is designed, including the optical detection circuit, voltage amplification circuit and low-frequency filtering circuit.