Study On Phase Identification Method Of Low Velocity Oil-water Two-phase Flow Based On Flow Pattern Control

Most of the current domestic onshore oilfield in high water content stage,the mixture of oil and water two phase flow state exists wide range,all kinds of industrial production process is above oil and water two phase flow,with the domestic industrial areas of measurement,regulation and control the advancement of a series of technical optimization,the measurement precision of two phase flow also ushered in the new challenges.Because each other between different fluid flow under the condition of different flow,flow medium between different flow state of medium flow has a certain randomness,mixed media flow is very complex,also is varied,characteristic parameters of current process combined with the above problem,two phase flow research mainly from the perspective of the three major categories: the flow pattern study,phase holdup study,flow study,accurate identification of convection pattern,accurate measurement of phase holdup,accurate measurement of flow and other related problems urgently need to be solved.Based on the three research fields,researchers are constantly putting forward new ideas and looking for new methods.This research work for two-phase flow problem to solve phase hold on,flow split phase flow exist larger measurement intractable difficulties in measurement problems,this subject adopts the ground precision measurement of metro logical and inspecting work control method,the experimental device has small volume,high precision,easy to operate features such as,through the study of the dynamic separation of two phase flow fluid,the problems existing in miscible phase measurement are changed to the measurement for single-phase flow,which reduces the measurement difficulty and improves the measurement accuracy.The research adopts online separation method with the help of impedance water content meter to carry out phase separation measurement for phase state conversion.Under the gravity differentiation of the buffer device,the oil-water two-phase flow is converted into single-phase water,and the single-phase oil is passed through the output end of the experimental equipment.The problem that the original oil-water two-phase flow is affected by the variable flow pattern,which leads to the measurement results,is ignored.It is calculated separately on the premise that the volume of the buffer device remains unchanged.To phase based on flow regime identification of two phase flow regulation of the low velocity of it phase identification method,using the statistics theory and the analysis method of combining wavelet packet transform theory,analyses the wave signal,the time domain feature extraction is sensitive to signal variance,standard deviation,gradient characteristic value as the characteristic parameter,in the frequency domain,the frequency spectrum and amplitude spectrum as well as wavelet packet coefficient of the signal are extracted All-round recognition the vector of phase state identification,and the phase state online identification model is established by the improved coefficient algorithm based on the grid search of support vector machine.The establishment of this model realizes the machine identification and accurate measurement of oil-water two-phase flow phase state,which lays a foundation for the measurement of oil-water two-phase flow phase hold up.Along with the experiments,in order to verify the research method of veracity and generalization performance,from the angle of error analysis and uncertainty of the angle on the discussion of the experimental results.Angle of authority,the results show that this measurement method is suitable for measurement,it split phase recognition rate reached 100%,confirmed that this experiment method has good applicability in oil-water two phase identification.