Study On The Change Of Flow Field Near The Bottom Of Perforation

Perforation completion is widely used both at home and abroad,the liquid flow condition near perforation completion hole wall is the key link to influence oil recovery index and so on,it is very important to study the liquid flow condition near perforation completion hole wall to inject the polymer well and the viscosity change.It can guide the practical application of oilfields.According to the characteristics of the flow field near perforation completion hole wall,the finite element method the steady state temperature field module of the large-scale finite element analysis software Ansys are used.The seepage field near the hole wall of perforation completion is simulated,and the three-dimensional model is established according to the actual and axisymmetric spiral perforation,and the velocity field and pressure field cloud around the hole are obtained by the reasonable grid partition and the pressure difference between the aperture and the boundary.From wellbore to stratum boundary,flow velocity is very small at wellbore end and linearly increases along the direction of perforation,at 0.95-1 time times the depth of the perforation,the flow velocity rises sharply,and reaches the maximum at the top of the hole,and enters the formation,because of the resistance action,in 1-1.1 time times deep hole depth interval,rapid descent,then slow down,after 1.2 times times perforation depth,tend to smooth.Along the direction of the perforation,the pressure gradually drops,dropping rapidly at the top of the perforations,and tends to stabilize after 1.2 times times the perforation depth.In this paper,the seepage field around the open hole completion wellbore is numerically simulated,and the seepage field around the wellbore of the open hole is compared with that of the perforation well.Compared with the open hole,the velocity and pressure vary greatly,but the formation boundary tends to be the same.By analyzing the changes of the boundary radius,perforation depth,perforation aperture,perforation perforation and wellbore radius,the influence on the hole wall near perforation completion is obtained,along with the formation boundary radius,perforation depth,viscosity,perforation aperture,perforation perforation and wellbore radius increases gradually,and the maximum flow velocity on the hole wall decreases gradually,with the increase of permeability,the flow velocity on the hole wall gradually increases,the maximum flow rate increases gradually,and with the formation boundary radius,perforation depth,perforation aperture,perforation perforation and wellbore radius increasing,The pressure on the hole wall gradually decreases and the minimum pressure on the hole wall increases gradually.The particularity and regularity of the flow field near the well bottom of perforation completion are revealed.