Flow field study on integrating straight and swirling jets for radial horizontal drilling
Abstract：In order to solve the contradiction between the diameter and the depth of borehole during high pressure jet drilling laterally radial horizontal wells, a new type of nozzle design was proposed which both advantages of round jet and swirling jet. Three dimensional flow fields inside and outside the nozzle were simulated in terms of RNG κ-ε tur- bulent model, also the flow structure and rock breaking characteristics with different nozzles were compared by the use of high-speed photography. The results show that the jet by the new designed nozzle has both features of round straight jet and swirling jet, with larger hole diameter than a conical round jet nozzle and deeper depth than a swirling jet noz- zle. Axial velocity of the jet formed by the designed nozzle has no potential core compared with round jet, and higher speed to a certain depth of drilling with no protrusion from hole bottom compared with swirling jet. Tangential velocity along the nozzle radial showing "M" type distribution can form a large aperture. Radial velocity distribution is symmet- rical with an obvious cross flow layer helping cuttings out from rock matrix. Flow field simulation results and the actual rock-drilling features are basically the same.
Keywords：integrating straight and swirling jetsimpact flow fieldradial horizontal wellRNG κ-ε turbulence model
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 1895-1900 )