基于石墨烯的充油高压压力传感器仿真设计  

Simulation Design of Oil⁃Filled High⁃Pressure Sensor Based on Graphene

作　　者：王吕昊 曹咏弘[1] WANG Lühao;CAO Yonghong(School of Aerospace Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学航空宇航学院,山西太原030051

出　　处：《中北大学学报（自然科学版）》2024年第5期565-572,共8页Journal of North University of China(Natural Science Edition)

摘　　要：压力传感器在较大压力范围内的输出结果难以稳定,传统压力传感器采用膜结构,在大压力作用下会产生强非线性,需要进行复杂的转化才能将测量数据转化为线性结果。本文基于石墨烯的压阻效应,通过圆筒状敏感结构,设计了一种高压压力传感器,能够在400 MPa范围内实现压力值的线性输出。该传感器结构主要由弹性金属膜片、可压缩硅油、圆筒结构以及石墨烯敏感膜组成。采用理论与仿真分析对传感器结构进行了优化设计,通过分析膜片厚度设计了在400 MPa压力范围内只产生弹性应变的金属膜片尺寸结构;运用流固耦合方法对传感器整体结构进行了仿真分析,明确了圆筒结构尺寸与外壁面应变大小的关系以及与整体结构固有频率的关系,通过寻找最大应变部位得出石墨烯敏感膜安装的合理位置;最后探究了圆筒结构外壁面的应变与传感器测量压力的线性关系。结果表明,设计的传感器结构可在400 MPa压力内工作,传感器圆筒结构的合适尺寸为长1.2 mm,厚度0.08 mm。在此尺寸下传感器的固有频率为127 kHz,圆筒结构外壁面应变最高可以达到2082με,在应变最高处安装石墨烯敏感膜,传感器结构的灵敏度可以达到5.205με/MPa;在0~400 MPa范围内传感器线性度结构线性度良好,结构线性相对误差仅有0.37%。The output result of the pressure sensor is difficult to be stable in a large pressure range.The traditional pressure sensor adopts the membrane structure,which will produce strong nonlinearity under the action of large pressure,and require complex transformation to convert the measured data into linear results.In this paper,based on the piezoresistive effect of graphene,a high-pressure sensor was designed through the cylindrical sensitive structure,which could realize the linear output of the pressure value within the pressure range of 400 MPa.The sensor structure was mainly composed of an elastic metal diaphragm,a compressible silicone oil,a cylinder structure and a graphene sensitive membrane.The sensor structure was optimized by theoretical and simulation analysis,and the metal diaphragm size structure which only produces elastic strain in the 400 MPa pressure range was obtained by analyzing the diaphragm thickness.Then the fluid-solid coupling method was used to simulate the deformation of the whole structure of the sensor,and the relationship between the cylinder structure size and the strain of the outer wall,the natural frequency of the whole structure was determined.The reasonable location of the graphene sen‐sitive membrane was obtained by finding the maximum strain location.Finally,the linear relationship between the strain on the outer wall of the cylinder structure and the pressure measured by the sensor was investigated.The results show that the designed sensor structure can work within the pressure range of 400 MPa,and the appropriate size of the sensor cylinder structure is 1.2 mm in length and 0.08 mm in thickness.At this size,the natural frequency of the sensor is 127 kHz,and the maximum strain on the outer wall of the cylinder structure can reach 2082με.The sensitivity can reach 5.205με/MPa when the graphene sensitive membrane is installed at the highest strain point.In the range of 0 to 400 MPa,the lin‐earity of the sensor structure is good,and the relative error of structure linearity

关 键 词：高压传感器 弹性元件 结构强度 流固耦合 固有频率 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]