Final Report Summary - COMPHYDRAULFRAC (Computer methods to predict three-dimensional hydraulic fracture networks) The world's ever-growing rate of energy consumption urges the improvement of techniques of both fossil fuels and renewable energy. Hydraulic fracturing is a technique applied to both categories of energy sources. It consists in pumping water at a very high pressure through pre-drilled wells into the ground and generating fractures in the rock. It can be employed to extract crude oil or natural gas from the rock; it can also facilitate the extraction of heat from the earth by forming a network of underground fractures. Its application requires the design of the fracturing strategy, including the quantity and pressure of the water to be injected.Hydraulic fracturing is expensive to study both on site and in a laboratory and only limited information can be obtained wherefrom. On the contrary, computer simulations are cost-effective and time-efficient in predicting the geometry of the fractures and thus can contribute to speeding the designing process.In this project, we planned to develop efficient simulation methods with the objective of accurately predicting the three-dimensional network of hydraulic fractures, taking into account rock self-contact, inhomogeneity, and poroelasticity. We also planned to build methodologies to incorporate stratigraphic data obtained from field technologies.In the second reporting period, the researcher was involved in the dissemination activity of participating the World Congress in Computational Mechanics by presenting the research progress on phase-field modelling of crack propagation, a step forward to be generalized to study hydraulic fracturing.