Numerical Simulation of Temperature and Stress Fields in the Rock Heating Experiment

P. Rálek[1], M. Hokr[1]
[1]Technical University in Liberec, Liberec, Czech Republic

Presented work is motivated by pre-realization phase of rock heating experiment in underground, testing properties for cyclic energy storage. Heating unit, installed in large borehole from end of a tunnel, is fixed to the rock face with the geo-polymer. Rest of the borehole is filled with isolation material. We used the Heat Transfer Module and the Structural Mechanics Module in COMSOL for modeling of the transient heat conduction with thermo-elasticity in 3D, both with parametrized material properties, in order to set working range of sensors placed in measuring boreholes spread around the main borehole. The largest mechanical loading emerges on heater-geopolymer-rock interfaces, but general shape of temperature and stress field outside the borehole is mostly influenced by rock properties.