大斜度井两层稳定模型岩屑传输规律研究

根据质量守恒定律和动量定理,建立了考虑悬浮层颗粒扩散、岩屑床中流体压力降的大斜度井中两层稳定岩屑传输数学模型。从环空返速、井斜角、岩屑床分数以及岩屑床中流体流动的附加压力降等方面进行了模拟研究,研究结果表明:岩屑床分数的增加、环空返速的提高有利于岩屑颗粒悬浮;随井斜角增加,悬浮层颗粒浓度减小;岩屑床面积较大时,进行大斜度井水力学设计时应考虑岩屑床中的流体压力降。

Study on Cuttings Transportation Tendency of the Dual Layer Stabilizing Model in Highly Inclined Well

A mathematical model on cuttings transportation of dual layer stabilizing in the highly inclined well is established based on the Law of Mass Conservation and Momentum Theorem, taking the fines spreading in the suspension layer and fluid pressure drop in the cutting bed into consideration. Stimulation studies were carried out from such aspects as annular velocity, hole inclination, bed fraction and additional pressure drop due to fluid flow in the cutting bed, etc., and the results showed that, with the increase of bed fraction and annular velocity, cutting fines obtains good suspension; with the increase of hole inclination, the concentration of fines in suspension layer decreases; while the cutting bed has larger distribution area, fluid pressure drop across the cutting bed should be considered in hydraulic design of the highly inclined well.