分布式光纤温度压力传感器设计

为了实现油田井下温度压力的全分布式测量,提出了一种基于光纤散射原理的分布式温度压力测量方法。该方法通过对普通光纤进行封装设计,制作成传感光纤。由于光纤传感器周围流体的温度和压力会对传感光纤内的散射光产生调制作用,通过光纤解调仪解调出光纤拉曼散射参数和布里渊散射频移就能够实现温度和压力的实时在线测量。实验结果表明:设计的分布式光纤温度压力传感器可以实现的温度测量分辨率为0.1 ℃,压力测量分辨率为0.07 MPa。基本满足油田井下温度压力测量的全分布式、实时在线、可靠性高、精度高、抗干扰能力强等要求。

Design of distributed optical fiber sensor for temperature and pressure measurement

In order to realize fully distributed measurement for temperature and pressure in an oil well, a measurement method of distributed temperature and pressure based on scattering theory of optical fiber is established. The method makes the common optical fiber into the sensing fiber through package design. Since the scattered light in the sensor fiber is modulated by the temperature and pressure of the fluid surrounding the optical fiber sensor, the real-time on-line measurement of the temperature and pressure is accomplished through the demodulation of the parameters of Raman scattering and Brillouin scattering frequency shift within the optical fiber by the optical fiber demodulator. Experimental results indicate that the distributed optical fiber sensor for temperature and pressure measurement can realize that the temperature resolution is 0.1 ℃ and pressure resolution is 0.07 MPa. It can satisfy the requirements of fully distributed, real-time, on-line, higher reliability, higher precision and strong anti-jamming for the measurement of temperature and pressure in an oil well.