Numerical modeling of saturation type and lateral pressure influences on thermo-mechanical stresses caused by laser drilling in granite and limestone

Abstract

Numerical methods for study effect of parameters on rock behaviour have increased in recent decades. Simulation is an important tool for analysis which the possibility of doing it is not feasible under experimental conditions and the possibility of analysis of thermo-mechanical stress and strain caused by the laser. In this study, the finite element method has been used to study thermal and mechanical stresses caused by drilling with laser ND: YAG in rock samples of limestone and granite. For this purpose, the software ABAQUS was used for thermal and mechanical analyses. After applying drilling rate and modeling laser drilling based on experimental tests, the effect of type of saturation and high lateral pressures on the rock laser drilling was studied. Results showed that the numerical model used is in good agreement with the experimental data. The thermo-mechanical stress developed in the rock has a direct relationship with the drilling specific energy. Also, in the limestone and granite, the maximum stress caused by laser drilling in the water-saturated rocks is higher than the oil-saturated and dry state.