Accurate Computation ERT Measurements With External Electrical Resistance

Electrical resistance tomography (ERT) is an advanced measurement technique due to low cost, rapid response, no radiation, and nonintrusiveness, but there is a natural relation between internal electrical resistance (IER) distribution and external electrical resistance (EER) relative to a detected field. The IER distribution can reconstruct all the detected objects within the field, while EER can greatly affect the measuring accuracy. So far, there is no effective method to compute the effect of EER. In this article, a general method is proposed to analytically compute all measurements in the existence of EER. Inversely, according to the interrelation between IER and EER, IER can be solved based on all available measurements. To validate the proposed method, an important parameter of solid-phase fraction (SPF) based on IER was computed in dredging engineering. Results show that the new method can compute the value of SPF more accurately than the existing method and thus can provide more accurate and practical measurements in the presence of EER.