基于光纤光栅的高压固体压力传感器研究

Research on Solid Pressure Sensor for High-pressure Measurement Based on Fiber Bragg Grating

固体内部压力是国防科技领域需重点监测的参数之一,目前使用较多的测压设备均存在电磁干扰严重、可靠性及准确性差等缺陷。针对以上不足,本研究设计了光纤光栅耐高压固体压力传感器。采用平面薄板作为弹性承压膜片,利用压力作用下的挠度,拉动压力敏感光栅产生轴向位移,实现压力传感。根据测压范围,对其结构进行理论计算,并进行有限元仿真,验证了本设计的可行性。在恒温条件下,进行了压力校准实验,并通过处于同一温度场的温补光栅进行温度补偿,修正应变光栅的温漂。实验结果表明,构建的承压光栅(FBG)压力传感器可以进行压力传感,测压上限可达50 MPa,线性度为99.2%。

Solid internal pressure is one of the important parameters in traffic bridge and defense field.However,the existing testing equipments have the defects of serious electromagnetic interference, poor reliability,and poor accuracy. To overcome the above problems,a fiber bragg grating( FBG) high pressure solid pressure sensor which used thin plates as elastic bearing diaphragm and applied the deflection under pressure to pull the pressure sensitive grating to realize pressure sensing axial displacement was designed. By calculating on the structure according to the measurement range and finite element simulation,its feasibility was confirmed. In the laboratory with constant temperature,the pressure calibration experiment was carried out,and the temperature compensation was performed by the temperature compensation grating in the same temperature field to correct the temperature drift of strain grating. Experimental results showed that the newly devised FBG pressure sensor could sense the pressure as high as 50 MPa,with a linearity of 99.2%.