Initial and boundary conditions in heat and water flow model

Hi to all,

I trying to solve transient heat convection and conduction model, coupled heat and water flow under the ground soils. The following messages has come during the solving:

% Failed to find consistent initial values.
% Singular matrix.

% There are 200200 void equations (empty rows in matrix) for the variable comp1.p. at coordinates: (0,-2), (0,-1), (0,-4), (0,-3), (0,-6), ...
% and similarly for the degrees of freedom (empty columns in matrix).
% Last time step is not converged.


Besides, I would like to ask how to put the previous results as initial conditions in the next model. For example using the transient model to calculate ground temperatures, and then use the last step results as initial temperature in coupled heat and water flow model.

Best regards

LIN