Permanent dynamic and static water holdup measuring device for ground wellhead

Abstract To adapt to the reality that a large number of wells are dispersed in the oilfield and the measured output fluid inside the wells contains less gas, a permanent dynamic and static water holdup measuring device for ground wellhead (PDSWHMD_GW) is designed, and a phase holdup system based on PDSWHMD_GW is developed for different oil-water flow. Specifically, the measurement mechanism of the measuring device was modeled and the results of its oil-water two-phase flow water holdup measurement were theoretically analyzed; The results of the electric field distribution of dynamic and static conductance-capacitance core detection components (DSCCCDC) were analyzed; On this basis, the performance indexes for the optimization of structural parameters are proposed and ring-shaped multistage conductance sensor (RMCS) parameter, cylindrical capacitance sensor (CCS) parameters, and RMCS-CCS distance are optimally designed. In addition, a permanently dynamic and static water holdup measuring device was developed, and experimental research was carried out on the built measuring platform. It was verified that the measuring devices showed good linearity between measurement results and actual values. The experimental results are analyzed for oil-water flow conditions such as the oil-water flow rate range of 5–70 m 3 d −1 and water holdup range of 50%–95% (Very fine dispersed oil-in-water flow (VFD&O/W),D&O/W, and dispersed oil-in-water slug flow), The vast majority of phase holdup have a measurement error of less than 5%. Both practice and simulation prove that measuring device has good performance.