“…Moreover, the study object in previous research is usually a section of straight pipe [12,13]. However, in the practical process of pneumatic conveying system, curving pipe, variable-diameter pipe and other special pipe structures are also commonly existed in transmission pipelines, and the flow characteristics around these special pipes are different from each other [14,15,16], so the performance researches of the sensors installed around these special pipes are also important. In this paper, by coupling of electrostatic and fluid fields, 3-D coupling models of straight pipe, curving pipe and variable-diameter pipes with 3 different sensor structures for concentration measurement are studied and the concentration distribution and the corresponding capacitance values of sensing electrodes can be obtained with varying time.…”