Governing equations for geothermal reservoirs

Balance laws and constitutive relations are developed for convective hydrothermal (liquid water and liquid water–steam) geothermal reservoirs. A fully interactive rock‐fluid system is considered; typical rock‐fluid interactions involve momentum and energy transfer and the dependence of rock porosity (and permeability) upon the fluid and rock stresses. The geologic stress‐strain behavior treatment permits the nonlinear and history‐dependent constitutive behavior of the material to be properly taken into account.