Study On Adaptability Evaluation And Parameter Optimization Of Different Types Of Perforating Charges

In this paper,to study the complex characteristics of non-Darcy flow near perforation wellbores and the characteristics of non-Newton fluid under the condition of polymer flooding,the mechanism of formation damage in the process of drilling and completion was analyzed.And then the determination experiment of perforating damage parameters was designed and carried out independently.According to numerical simulation,the complex law of non-Newton and non-Darcy flow near perforation wellbores under the condition of polymer flooding was studied,and the applicable conditions of different types of perforating charges were evaluated and verified under the condition of water flooding and polymer flooding.This paper mainly carried out the following three aspects:(1)The mechanism of drilling pollution and perforation damage were analyzed.Based on the mud cake sedimentation and conservation equation,erosion equation and Darcy equation,the prediction model of drilling pollution depth and pollution degree were established,which were used to predict the pollution parameters in the target block.The determination experiment of perforating damage parameters was designed and carried out independently.The results show that the thickness of crushed zone is between 10-12 mm when the core permeability is less than 1×10-3?m2,while the thickness is between 10-18 mm when the permeability is greater than 10×10-3?m2.(2)The percolation model of non-Newton and non-Darcy near perforation wellbores was established.The flow viscosity determination experiment of polymer solution in porous media was designed and carried out,and the experimental results show that the flow viscosity increases with the increase of molecular weight and core permeability;the flow viscosity of polymer solution is far less than the apparent viscosity,so using the apparent viscosity to calculate the pressure drop of polymer solution in the reservoir will cause a large error.Therefore,the real flow viscosity of the polymer solution should be used to calculate the pressure drop in the process of actual production.The experimental results provide scientific basis for numerical simulation of polymer flooding.(3)Based on the percolation model of non-Newton and non-Darcy near perforation wellbores and the measurement results of flow viscosity of polymer solution in porous media,the numerical simulation was carried out to study the flow efficiency of different types of perforating charges under water flooding and polymer flooding,and the sorting of perforating effect under different conditions was given: under the condition of water flooding,the perforating effect of deep penetration charges is best(penetration depth is larger than 639 mm),followed by conventional charges,while the effect of large aperture charges is worst(pore size is larger than 16 mm).Under the condition of polymer flooding,the perforating effect of large aperture charges is better than conventional charges,but the effect of deep penetration charges is still the best.The research results of this paper enrich the theory of charge types and perforation parameters optimization under polymer flooding,which have great engineering significance to the construction design of perforation completion under the condition of polymer flooding or ASP flooding.