Análise Numérica de Teste Experimental de Poço de Petróleo

Abstract

An experimental test was developed to evaluate the structural behavior of the cement sheath of an oil well which is submitted to steam injection cycles. Five cementitious systems were tested and the thermal gradients that cracked the specimens together with the crack widths were obtained for each material. Furthermore their mechanical properties such as compressive and tensile strength, Young's modulus and Poisson´s ratio were also measured. Finite element analysis with software DIANA TNO© was performed in a thermomechanical model with axisymmetric geometry. The stress analysis showed that the increase in temperature creates tangential tensile stresses that cause the failure of the material. These results agree with published data on numerical modeling of wells. Although the numerical and experimental results presented the same tendency some quantitative differences in the stresses calculations have been observed. This can be due to simplified hypothesis that was used in the numerical model such as the non-consideration of creep and the invariability of the thermal properties with temperature.