水力喷射压裂孔内压力分布研究

水力喷射压裂工艺是集水力射孔和压裂一体的新型油田增产技术。在室内实验基础上， 运用流体力学计算方法， 对水力喷射压裂孔道内压力场进行计算， 得到了井下水力射流在地层孔道内的压力及速度分布， 揭示了喷嘴空间位置、 喷嘴数量、 孔道形状、 喷嘴压降和喷嘴直径对孔道压力的影响规律。结果表明：高速射流之间具有很强的独立性， 喷嘴空间位置和喷嘴数量不会影响孔道内压力； 水力射流在不同形状孔道内产生的压力相同； 孔道压力随喷嘴压降和喷嘴直径的增大而增加。

Jetting Pressure Field in Formation Cavities during Hydrajet Fracturing

Hydrajet-fractruing is a new stimulation technique in oilfield. It is very necessary to study jet parameters.Based on the experiments and computational method of fluid dynamics， the jet pressure field around a cavity hasbeen calculated. The velocity and pressure in cavity is obtained by fluid simulation. The following parameters wereanalyzed： nozzle space location， the number of jet， cavity shape， differential pressure and nozzle diameter. Theresult shows that the pressure in cavity will increase with the drop of nozzle pressure and the increase of nozzlediameter. The jetting stream creates the same pressure in the cavities in spite of their different shapes. The locationand the number of nozzle have no influence to the cavity pressure. The conclusions can provide scientific basis forthe oilfield performance of hydrajet-fracturing.