Numerical Simulation of Self-Sensing Time Domain Reflectometry for Damage Detection of Carbon Fiber Reinforced Polymer Plate

摘要

This study is an analytical investigation of time domain reflectometry (TDR) for carbon fiber reinforced polymer (CFRP) composites using numerical simulation software. This process is called self-sensing TDR because the carbon fibers themselves are used as the sensors. A previous study conducted experimental investigations of this process using parallel aluminum plates. This study uses finite difference time domain analysis for simulations of a transmission line structure for the self-sensing TDR. Details of the effects of the orthotropic electric conductance are investigated analytically. The simulation results show that the electromagnetic waves propagate rapidly in the transverse direction and that the effects of the orthotropic conductance seem to be negligible. An additional simulation using a pair of square CFRP plates reveals that the electromagnetic wave is affected by the orthotropic conductance. The effect is nevertheless very small when compared with the actual ratio of the electric conductance between the fiber direction and the transverse direction.