A Quick Approximation Method for Transient Thermal Stress Analysis in Well Cementing

Transient heat transfer is considered frequently in operations involving thermal flooding for EOR/IOR, pressure pumping during reservoir stimulation, geothermal wells, and HP/HT environments in general. These operations have a critical impact on the integrity of wellbore cementing. Generally, engineers use complex simulation software packages with finite element analysis (FEA) to tackle these kinds of problems. This methodology is time-consuming and costly. In this paper, we propose a new solution with an approximation method to analyze transient stress responses to thermal variation in well cementing. We decouple the differential equations from heat transfer, stress-strain relations and continuum equation. The transient temperature distribution is solved from an approximation method, and then the stress distribution profiles are obtained by superimposing transient temperature effects on thermal stress and strain profiles. The results from our simulation are presented in our case studies. The transient temperature distribution profiles in casingcement-formation are provided by this simulator. The transient radial stress and tangential stress distribution in a cement sheath system as a function of radial distance are discussed. This approach allows field engineers to conduct quick analyses without loss of simulation quality within a certain acceptable degree.