Study On Settlement And Migration Law Of Proppants In Annulus Near Packer

The hydraulic perforation and fracturing with coiled tubing is a new technology,which integrates sand blasting perforation,hydraulic fracturing and annulus injection technology.The technology can realize accurate reconstruction of horizontal wells,unlimited fracturing stages,the full internal size,quick construction,and do not need to drill the plug,low comprehensive cost.However,when the technology performed in site,the proppants are transported into the annulus space between the packer and the perforation tool,forming the proppants bed,leading the packer could not unlock successfully after perforation.In order to solve the problem,consider the coupled effect between fluid-solid and solid-solid,the Euler-Euler double fluid two-phase flow model,a numerical simulation of the standard ?-? turbulence model and the coupled algorithm is used to study the effects of the displacement,sand ratio,viscosity of fracturing fluid,proppant density and particle size on the height of bed,the length of bed and the proppant concentration,the law of configuration under different conditions is obtained.The result shows: with the development of fracturing,the majority of proppants are converted into the perforations,the minority pass the annulus space between perforation tool and packer,transport into the annulus near packer,the velocity of migration decay quickly and settle down under the action of fluid velocity loss and enlargement.The growth of proppant bed height reduces the area the fluid flow through,leads to increase flow velocity,enhances the flow fluidization,proppants are carried to the deeper annulus near packer,the whole process of proppant settlement & migration acts as the growth in height and length.At the same time,with the growth of displacement,sand ratio,proppant density,the proppant concentration near packer increases.With the growth of fluid viscosity and proppant size,the proppant concentration near packer reduces.Designed a double perforation tunnel horizontal jet fracturing simulation,20/40 mesh and 40/70 mesh,two different size of horizontal particles are carried out by different displacement,sand ratio,the fracturing fluid viscosity.Indoor experimental results are consistent with the results of numerical simulation.Numerical simulation and laboratory experiments verify the validity of the proppant settlement & migration rule,reveal the law of proppant settlement & migration in annulus near packer together,providing the guidance for the hydraulic perforation and fracturing with coiled tubing.