Geometry Structure Optimization Of Conductance Probe Using In Horizontal Producing Profile Well Logging

The hold-up is an essential parameter to describe and analyze the flow characteristic for oil-water two phase flow. Due to the polymorphism of oil-water two-phase flow pattern, the traditional conductance probe applied in vertical well is unsuitable for measuring hold-up of oil-water two-phase flow in horizontal pipe. It is necessary to optimize the geometry structure parameters of conductance probe.The Finite Element Method (FEM) is used to calculate the electric field inside the sensor model. Then the concepts of uniform degree, relative error of voltage in the symmetrical section of probe are used to investigate the distribution of the electric field inside the probe and determine the height and thickness of excitation electrodes, the space range between excitation electrodes. By introducing the concept of sensitivity, the sensitivity distribution is calculated during various spaces of excitation electrodes and measuring electrodes. Subsequently, the concepts of total information volume, effective information volume, concentration of effective information are applied to determine the structure parameters of probe preliminarily.A further study on the responses of probe having various structure parameters is done under Do/w, Do/w&w, ST and ST&MI oil-water two-phase flow patterns. The simulation results have been compared with available theoretical models. The results shows that simulation results are near the prediction curves, and the structure parameters contribute less to the simulation results.To analyze flow characteristics of oil-water two-phase flow in horizontal well bore, the methods of characteristics of attractor morphology and Wigner-Ville Distribution are applied to conductance fluctuation signals. By placing reference section in the field of chaotic attractor, the relationship between characteristics of attractor morphology and transition of flow pattern in oil-water two-phase flow reveals that the stratified flow pattern and dispersion flow pattern can be distinguished using four-order characteristic of attractor morphology. It shows that the characteristic of attractor morphology method combining with conductance fluctuation signals works well for identifying oil-water two-phase flow pattern.