= r_psolve(refSol);
    
    % inexact solution
    msSol = psolve(msSol);
    
    % store data for plotting 
    caseData.msSol{casenr} = msSol;
    caseData.g_fine{casenr} = g_fine;
    caseData.rock{casenr} = rock;
    
    %% Transport loop
    % Solve a linear transport problem with fixed fluxes
    % computed from the pressure equation

    % Simulation time is 1 PVI
    if casenr == 1
    T      = sum(g_fine.cells.volumes.*rock.poro)./rate;
    dT     = T/10;
    end
    
    %% Start the main loop
