基于BOTDA传感技术的空间分辨率研究

空间分辨率是BOTDA传感系统的一个重要参数,其主要取决于泵浦脉冲光的宽度。为了提高BOTDA系统的空间分辨率,在不改变泵浦脉冲光宽度的情况下,采用螺旋式盘绕传感光纤的方法,分析了布里渊散射传感原理,理论上分析采用螺旋式盘绕光纤对提高实际测量空间分辨率的影响。实验中泵浦脉冲光宽度为10 ns,BOTDA系统采样间隔为0.4 m。采用1 m长螺旋式盘绕传感光纤监测0.5 m管线轴向温度分布,监测空间分辨率为0.5 m。分析结果表明,采用螺旋式盘绕光纤更有利于提高监测管线温度场的空间分辨率。

Research on Spatial Resolution Based on BOTDA Sensing Technology

Spatial resolution is an important parameter of Brillouin optical time domain analysis （BOTDA） sens？ing system, which depends on the width of pump pulse light. To improve the spatial resolution of BOTDA system, spiral coiled optical fiber method is used without changing the width of pump pulse light. Brillouin scatter sensing principle is analyzed. The influence on improving spatial resolution in actual measurement process using coiled op？tical fiber is analyzed on theory. In the experiment, the width of pump pulse light is 10 ns, the sampling interval of BOTDA system is 0.4 m. The spiral coiled optical fiber with 1 m length is used to monitor the axial temperature dis？tribution of 0.5 m pipeline and monitoring spatial resolution is 0.5 m. Analysis results show that spiral coiled optical fiber is more available to improve the spatial resolution in monitoring pipeline temperature field.