非対称螺旋型極板を用いた静電容量式ボイド率計の精度検証

抄録

A capacitance sensor for void fraction adopting asymmetric helical electrodes is proposed to avoid adverse effects of gas-liquid two phase flow distribution on measurement accuracy. In this research, in addition to verification in the Stratified flow already performed, the accuracy in the Dispersed flow was confirmed using an Electric Field Analysis (EFA). The analysis was performed for the proposed three types of models (Helical type, Square type, Hexagonal type). In order to simulate the Dispersed flow, the fluid element was divided into 325 parts and the gas - liquid distribution was randomly assigned. In the result of the electric field analysis, the maximum EFA error was 7.07% in the case of Helical type, and the standard deviation was 1.62% even in the model with the lowest precision. Therefore, it was confirmed that the capacitance sensor for void fraction adopting asymmetric helical electrodes can maintain accuracy and precision even in the Distributed flow.