中文摘要：

直旋混合射流兼具直射流和旋转射流的优点,为了进一步探究喷嘴结构参数对流场及破岩特性的影响,该文采用数值模拟方法,分析了叶轮中心孔直径、叶轮旋槽出口角度和面积、混合腔和收敛角等喷嘴结构参数对射流流动结构的影响规律。结果表明,射流轴心速度衰减主要受叶轮中心孔直径和旋槽出口角度的影响;截面切向速度分布规律主要受叶轮中心孔直径、叶轮旋槽出口角和截面积、混合腔收敛角及喷距的影响。对比不同结构参数下的破岩实验发现,轴心速度衰减梯度小,有利于提高喷嘴的有效作用距离,轴向速度大,有利于提高钻孔深度,切向速度峰值和作用面积大,有利于提高钻孔孔径。研究结果可为径向水平井射流钻头结构参数设计提供依据。

英文摘要：

The straight-swirling integrated jet has advantages of both the straight jet and the swirling jet. To further investigate the influence of structural parameters and rock breaking characteristics of the straight-swirling integrated jet on its flow field, the numerical simulation method is used to make a research on several structural parameters： the diameter of the impeller center hole, the angle and the area of the impeller slot, the length and the convergence angle of mixing chamber, and so on. The results reveal that the axial velocity attenuation rule is influenced by the diameter of the impeller center hole and the angle of the impeller slot; the distribution of the tangential velocity is influenced by the diameter of the impeller center hole, the angle and the area of the impeller slot, the convergence angle of the mixing chamber, and the spray distance. Compared with the results of rock breaking tests, those are found that the lower axial velocity attenuation gradient is, the longer effective spray distance it has. The higher axial velocity it has, the longer drilling depth it achieves. The higher tangential velocity and larger effective area it has, the larger hole diameter it achieves. The study would provide a reference for jet bit struc~re design in radial horizontal drilling.