Dynamical analysis of high-pressure supercritical carbon dioxide jet in well drilling

This paper presents the design of an experimental setup and mathematical and physical models to determine the dynamical characteristics of the high-pressure supercritical carbon dioxide (SC-CO₂) jet with a highly potential applications in the well drilling. The effects of three major factors on the wellbore dynamical characteristics of the high-pressure SC-CO₂ jet, i.e., the nozzle diameter, the standoff distance and the jet pressure are determined. It is indicated that the pressure of CO₂ reduces severely in the SC-CO₂ jet impact process. It is also found that the bottom-hole pressure and the temperature increase as the nozzle diameter increases but de- crease with the increase of the standoff distance. The higher the jet pressure at the wellbore inlet is, the higher the pressure and the lower the temperature at the bottom-hole will be.