The sensitivity field characteristics of coaxial capacitance sensor used in oil-water two-phase flow

By using finite element method (FEM) we first investigate the affect of the electrode length l, thickness of the insulating coat t, the diameter of the inner electrode d and the inner diameter of the outer electrode D on the distribution characteristic of the electric field and the sensitivity field of coaxial capacitance sensor, and then figure out the optimum sensor geometry based on the computed result of the sensitivity field. Additionally, through the investigation of the affect of oil bubble size on the sensor response characteristics, we find that for DO/W flow with high water volume fraction (Y₀ ≤ 10%) the sensor shows good response linearity and sensitivity with the variation of the oil volume fraction.