小尺寸环空螺旋衰减流测速方法探讨

STUDY ON FLOW RATE MEASURING METHOD FOR HELICAL ATTENUATION FLOW OF SMALL SIZE ANNULAR SPACE

根据毕托管测速原理 ,针对油气井同心环空螺旋流三维流动特征 ,设计制作了一种“拟毕托管测速仪” ,结合吊线法 ,可以用于小尺寸模拟三维流场的流速测量。该法克服了非接触流速测量仪 (如激光测速仪 )价格昂贵 ,且受被测流体透明度等的限制 ,又解决了现有毕托管用于小间隙流道接触式流速测量干扰性大、不能测量三维流场流速的问题。利用所制作的“拟毕托管测速仪”测量了螺旋衰减流流场 ,分析出了螺旋流流速分布的基本特征。

According to the principle of Beeto flow rate measuring, and aiming to the 3-D flowing characteristics of helical flow in the concentric annular spaces of oil and gas wells, a 'pseudo Beeto flow rate meter' is developed, which can be used for flow rate measuring of simulated small size 3-D flowing field with lifting line method. The flow rate meter overcomes the disadvantages of un-contact flow rate meter(e.g. laser flow rate meter), such as expensive price, and the measurement limited by the transparency of measured fluid. Also, the meter solves the problems, such as big disturbance and the flow rate of 3-D flow field can't be measured when the existing Beeto tube is used for contact flow rate measuring of small space channel. Using the pseudo Beeto flow rate meter, the flow field of helical attenuation flow is measured, and the characteristics of the flow rate distribution of the helical flow are derived.