Modeling hydrodynamics of the flushing fluid intermittent flow in the hydraulic system of the diamond bit

Purpose. To study the effect produced by the intermittent flushing on hydrodynamic processes in the hydraulic system of a diamond bit. Methods. Mathematical modeling methods and CFD experiment. Findings. A mathematical model of hydrodynamic processes in the flushing ports of the drill bit hydraulic system in conditions of drilling with intermittent flushing is presented. Numerical study of hydrodynamic processes for symmetric intermittent flushing was conducted. The velocity and pressure fields in the flow of the drilling fluid (water) in the ports were obtained. It was shown that pressure changes significantly in the flow with formation of low pressure zones and low intensity vortex during the pause in feeding. Analysis of the obtained effects shows that the use of intermittent flushing allows to control the hydrodynamic processes and influence the diamond drill bit operation. Originality. Hydrodynamics of intermittent flow of the flushing fluid in the hydraulic system of drill bits was investigated for the first time ever. The obtained results are the basis to theoretical substantiation of technological effects during drilling with intermittent flushing, such as improving bottom hole cleaning from slurry and increasing drilling speed. Practical implications. The results of the study are important for developing a technique and technology of diamond drilling with intermittent flushing.