The problem describes a heat source embedded in a fluid--saturated porous medium.
The problem describes a heat source embedded in a fluid-saturated porous medium.
The spherical symmetry is modeled using a 10 m x 10 m disc with a point heat source ($Q=150\; \mathrm{W}$) placed at one corner ($r=0$) and a curved boundary at $r=10\; \mathrm{m}$. Applying rotational axial symmetry at one of the linear boundaries, the model region transforms into a half-space configuration of the spherical symmetrical problem.
The initial temperature and pore pressure are 273.15 K and 0 Pa respectively.
The axis-normal displacements were set to zero along the symmetry (inner) boundaries, whereas the pore pressure as well as the temperature are set to their initial values along the outer (curved) boundary.
The heat coming from the point source is propagated through the medium causing it to heat up and expand until equilibrium (consolidation) is reached.
The corresponding derivation of the analytical solution can be found in the work cited below.
The initial temperature and the pore pressure are 273.15 K and 0 Pa, respectively.
The axis-normal displacements along the symmetry (inner) boundaries were set to zero, whereas the pore pressure, as well as the temperature, are set to their initial values along the outer (curved) boundary.
The heat coming from the point source is propagated through the medium, causing it to heat up and expand until equilibrium (consolidation) is reached.
The corresponding derivation of the analytical solution can be found in the works cited below.
The main project input file is `square_1e2.prj`. Geometry and mesh are stored in `square_1x1.gml` and `quarter_002_2nd.vtu`.
## Equations
The problem equations can be found in the original work of Booker and Savvidou (1985) or in Chaudhry et al. (2019).
The problem equations can be found in the original work of Booker and Savvidou (1985) or Chaudhry et al. (2019).
The analytical solution of the coupled THM consolidation problem can be expressed in terms of some derived parameters:
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@@ -89,7 +89,7 @@ For the stress components the corrected expressions can be found in the work of
## Results and evaluation
The analytical expressions (12-16) together with the numerical model can now be evaluated at different points as function of time or for a given time as function of their spatial coordinates.
The analytical expressions (12-16) together with the numerical model can now be evaluated at different points as a function of time or for a given time as a function of their spatial coordinates.
The results below were taken from the benchmark published in Chaudhry et al. (2019) and might slightly differ from the benchmark in the OGS6 repo.
{{< img src="../images/resp_vs_t_square.png" >}}
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@@ -102,7 +102,7 @@ In the pictures above, the analytical and numerical results for temperature ($T$
(Figures were taken from Chaudhry et al. (2019).)
The absolute errors between OGS6 and the analytical solution for temperature, pressure and displacement are depicted below. For all three response variables one observes that the error reaches it's maximum around the same time, when also the slope of the response variable is maximal.
The absolute errors between OGS6 and the analytical solution for temperature, pressure, and displacement are depicted below. For all three response variables, one observes that the error reaches its maximum around the same time when also the slope of the response variable is maximal.
