开放式电阻抗成像激励策略研究

Research on excitation strategy of open electrical impedance tomography

复合材料被广泛用于航空航天领域,实现其结构健康监测对提高适航审定的损伤容限探测水平、降低检测成本具有重要意义。针对飞机使用的碳纤维增强复合材料,利用碳纤维的自传感特点及结构损伤的电学敏感特性,提出开放式电阻抗成像无损检测方法,以实现非侵入、无辐射、低成本的快速无损结构健康监测。根据材料结构损伤特点,构建6×6阵列电极及5种电流激励模式,运用有限元方法求解不同模式下的正问题,并从测量和成像精度角度分别进行对比评估。综合实验结果表明,间2激励模式整体表现较优,可为下一步结构损伤参数提取的研究提供依据。

Composite materials are widely used in aerospace field, achieving structural health monitoring is significant for improving the detection level of damage tolerance during the process of airworthiness certification and reducing test cost. Aiming at the carbon fiber reinforced composite material widely used in aircraft, using the self-sensing and the sensitive electrical characteristics of carbon fiber reinforced polymer （CFRP） structural damage, a new non-destructive test method based on open electrical impedance tomography is proposed to realize fast structural health monitoring with non-invasion, non-radiation and low cost. According to the characteristics of material structural damage, a 6 × 6 electrode array and 5 current excitation strategies are proposed. The corresponding forward problems in different modes are calculated with finite element method, and the different excitation strategies are compared and evaluated from the perspectives of both measurement and imaging precision. The experiment results show that the excitation mode of electrodes with two electrode interval has better overall performance, which can provide an effective basis for the next step research of extracting structural damage parameters.