A Study Of Downhole Ultrasonic Doppler Flow Measurement Technique

In oil and gas field exploitation, the accurate measurement of oil, gas and water three-phase flow has an important meaning, which is the key technology of optimizing production and intelligent well. It has played an important role in flow control, reservoir protection, prolong service life, evaluating the stimulation measure effect and analysising reservoir characteristics. There are many different changing flow styles when three-phase flow in pipe,such as the oil composition,the water rate,the gas rate and the emulsification phenomenon, which make the measurement be more difficult. So the accurate measurement of three-phase flow has been the cutting-edge topics in domestic and international.The paper mainly disseusses the oil, gas and water three-phase flow measurement system and introduces a downhole multiphase flow measurement based on ultrasonic Doppler. According to the measuring environment and the characteristics of objects, the researcher has developed the Doppler ultrasonic transducer, designed and implemented the downhole ultrasonic Doppler hardware circuit, and completed the Doppler downhole flow measurement principle prototype eventually. The measurement solution has the advantages of non-invasive, real-time online measure and low cost.On the basis of many indoor experiments, the outdoor experiment used land test Wells has been made.After a great deal of indoor and outdoor tests and studies, the developed downhole ultrasonic doppler flow measurement system has been confirmed which has good performance and reasonable structure. It has been applied in the natonal major project of "Deep water flow measurement system research", and will play an important role in the dowmhole flow measurement system reserch and performance test.