S-ALE Analysis of the Effects of Perforating Fluid Properties on Perforating Tubing String Strength Under Dynamic Loading in High-Pressure Deep Wells

During perforating operations in high-pressure deep wells, detonation-induced pressure waves propagate through the perforating fluid and excite local tubing motion and stress. Previous studies have addressed shock pressure and tubing-string vibration, but the combined effects of fluid density and viscosity on local axial motion and reference yield margin remain insufficiently quantified under consistent loading conditions. A coupled structured arbitrary Lagrangian–Eulerian (S-ALE) fluid–structure model was used to examine 16 density–viscosity combinations at an initial pressure of 96 MPa. Axial displacement and acceleration were evaluated near the equivalent charge, and von Mises stress was evaluated in a tubing element adjacent to the packer. The safety factor of the tubing string was calculated based on the reference yield strength of P110 steel. At fixed viscosity, increasing density from 1.0 to 2.5 g/cm3 increased peak axial displacement, axial acceleration, and equivalent stress by up to 125.13%, 60.66%, and 31.13%, respectively. At fixed density, increasing viscosity from 20 to 110 mPa·s reduced these peaks by up to 24.53%, 46.45%, and 14.86%, respectively. The local reference yield safety factor ranged from 1.21 to 1.79. Within the modeled conditions, lower density and higher viscosity reduced the predicted local axial motion and equivalent stress.