.. _diffusion-darcy_flow_multicomp: diffusion/darcy_flow_multicomp.py ================================= **Description** Each of the two equations describes a flow in one compartment of a porous medium. The equations are based on the Darcy flow and the i-th compartment is defined in :math:\Omega_{i}. .. math:: \int_{\Omega_{i}} K^{i} \nabla p^{i} \cdot \nabla q^{i}+\int_{\Omega_{i}} \sum_{j} \bar{G}\alpha_{k} \left( p^{i}-p^{j} \right)q^{i} = \int_{\Omega_{i}} f^{i} q^{i}, .. math:: \forall q^{i} \in Q^{i}, \quad i,j=1,2 \quad \mbox{and} \quad i\neq j, where :math:K^{i} is the local permeability of the i-th compartment, :math:\bar{G}\alpha_{k} = G^{i}_{j} is the perfusion coefficient related to the compartments :math:i and :math:j, :math:f^i are sources or sinks which represent the external flow into the i-th compartment and :math:p^{i} is the pressure in the i-th compartment. .. image:: /../doc/images/gallery/diffusion-darcy_flow_multicomp.png :download:source code  .. literalinclude:: /../sfepy/examples/diffusion/darcy_flow_multicomp.py