Research On Sanding Signal Processing Method Of Oil And Gas Wells Based On Ultrasonic Phased Array Speciality Signal And Information Processing

Sand monitoring method is an important way to understand the sand production status of oil and gas wells,which has a great impact on the sand production effect,cost and oil and gas well production.The traditional sand monitoring method has a fixed angle between the sensor and the pipe,which is seriously affected by the fluid flow rate.When monitoring the sand production in the gas well,due to the faster flow rate of the gas belt sand,the angle between the direction of the sand particles striking the pipe wall and the horizontal plane is smaller than the sand in the oil well is monitored,the sand particles hit the wall due to the slower fluid velocity of the oil belt,the angle between the direction and the horizontal plane is larger.Therefore,when monitoring the sand production of oil and gas wells,it is necessary to continuously adjust the angle between the sensor and the pipe wall according to the change of the fluid flow rate.However,the traditional oil and gas well sand monitoring signal processing method is based on the time domain and frequency domain filtering methods,which cannot solve this problem.Therefore,an ultrasonic phased array based oil and gas well sanding signal processing method is proposed.The method is based on the array signal processing method.Firstly,according to the near-field direction of arrival estimation theory of the ultrasonic phased array,the main direction of the sand striking the tube wall is detected,and the airspace of the sanding signal is realized by guiding the receiving array to the region.In addition,on this basis,combined with the existing sand signal analysis method,the sand signal is combined and filtered in the air,frequency and time domain to improve the signal-to-noise ratio of the sand signal,and finally the sand is decomposed in real time according to the amplitude of the signal.the amount.The specific contents are follows:(1)The theoretical model based on ultrasonic phased array is established,and the near-field focusing model of the sand monitoring system is obtained through Matlab simulation.(2)Based on the near-field focused odd-numbered array sensor model,the near-inference is derived.The general model of the field-focusing even-numbered array sensor.(3)The spatial filtering algorithm of the focused ultrasound phased array is studied,which is to judge the area where the sand hits the pipe wall(the direction of arrival).(4)The wave velocity forming algorithm is studied,and the ultrasonic wave is analyzed.Thepower spectrum can be used to distinguish the specific orientation of the sand striking the pipe wall through the power spectrum.(5)In order to improve the accuracy of the system,the factors affecting the accuracy of the system are analyzed,including the number of sensor elements,the spacing of adjacent elements of the sensor,the focal length of the near field focus,the influence of the signal frequency,the influence of the signal lobes,etc.(6)considering the portability of the system,the appropriate sensor size and number of array elements are preferred.(7)The system is built a sand monitoring software based on LabVIEW,which makes the sand monitoring area more intuitive in the field construction.On the basis of various functional studies,the test of sand monitoring system was carried out using the existing sand monitoring platform of the laboratory.It is found through experiments that the method of oil and gas well sand signal processing based on the ultrasonic phase-control array can realize adaptive high-precision sand production at different flow rates by scanning various regions of the pipeline without moving the sensor.It is estimated that the accumulated sand output value and the given sand production value deviation within five percent,achieving a higher monitoring accuracy.