 <OpenGeoSysProject>

   <meshes>

     <mesh>ParallelPlate.vtu</mesh>

     <mesh>ParallelPlate_top.vtu</mesh>

     <mesh>ParallelPlate_bottom.vtu</mesh>

     <mesh>ParallelPlate_left.vtu</mesh>

     <mesh>ParallelPlate_right.vtu</mesh>

   </meshes>

   <processes>

     <process>

       <name>ff</name>

       <type>StokesFlow</type>

       <integration_order>3</integration_order>

       <process_variables>

         <liquid_velocity>liquid_velocity</liquid_velocity>

         <pressure>pressure</pressure>

       </process_variables>

       <specific_body_force>0 0</specific_body_force>

     </process>

   </processes>

   <media>

     <medium id="0">

       <phases>

         <phase>

           <type>AqueousLiquid</type>

           <properties>

             <property>

               <name>viscosity</name>

               <type>Constant</type>

               <value>5e-3</value>

             </property>

           </properties>

         </phase>

       </phases>

     </medium>

   </media>

   <time_loop>

     <processes>

       <process ref="ff">

         <nonlinear_solver>basic_picard</nonlinear_solver>

         <convergence_criterion>

           <type>PerComponentDeltaX</type>

           <norm_type>NORM2</norm_type>

           <abstols>1.e-6 1.e-6 1.e-6</abstols>

         </convergence_criterion>

         <time_discretization>

           <type>BackwardEuler</type>

         </time_discretization>

         <time_stepping>

           <type>FixedTimeStepping</type>

           <t_initial>0</t_initial>

           <t_end>2</t_end>

           <timesteps>

             <pair>

               <repeat>2</repeat>

               <delta_t>1</delta_t>

             </pair>

           </timesteps>

         </time_stepping>

       </process>

     </processes>

     <output>

       <type>VTK</type>

       <prefix>ParallelPlate</prefix>

       <suffix>ts{:timestep}_t_{:time}</suffix>

       <timesteps>

         <pair>

           <repeat>2</repeat>

           <each_steps>1</each_steps>

         </pair>

       </timesteps>

       <variables>

         <variable>liquid_velocity</variable>

         <variable>pressure</variable>

         <variable>pressure_interpolated</variable>

       </variables>

     </output>

   </time_loop>

   <parameters>

     <parameter>

       <name>kappa</name>

       <type>Constant</type>

       <values>1.157e-12</values>

     </parameter>

     <parameter>

       <name>porosity</name>

       <type>Constant</type>

       <value>1</value>

     </parameter>

     <parameter>

       <name>decay</name>

       <type>Constant</type>

       <value>0</value>

     </parameter>

     <parameter>

       <name>Dirichlet0</name>

       <type>Constant</type>

       <value>0</value>

     </parameter>

     <parameter>

       <name>v0</name>

       <type>Constant</type>

       <values>0 0</values>

     </parameter>

     <parameter>

       <name>p0</name>

       <type>Constant</type>

       <value>200000</value>

     </parameter>

     <parameter>

       <name>p_in</name>

       <type>Constant</type>

       <value>200039.8</value>

     </parameter>

     <parameter>

       <name>p_out</name>

       <type>Constant</type>

       <value>200000</value>

     </parameter>

   </parameters>

   <process_variables>

     <process_variable>

       <name>liquid_velocity</name>

       <components>2</components>

       <order>2</order>

       <initial_condition>v0</initial_condition>

       <boundary_conditions>

         <boundary_condition>

           <mesh>ParallelPlate_top</mesh>

           <type>Dirichlet</type>

           <component>0</component>

           <parameter>Dirichlet0</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>ParallelPlate_bottom</mesh>

           <type>Dirichlet</type>

           <component>0</component>

           <parameter>Dirichlet0</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>ParallelPlate_top</mesh>

           <type>Dirichlet</type>

           <component>1</component>

           <parameter>Dirichlet0</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>ParallelPlate_bottom</mesh>

           <type>Dirichlet</type>

           <component>1</component>

           <parameter>Dirichlet0</parameter>

         </boundary_condition>

       </boundary_conditions>

     </process_variable>

     <process_variable>

       <name>pressure</name>

       <components>1</components>

       <order>1</order>

       <initial_condition>p0</initial_condition>

       <boundary_conditions>

         <boundary_condition>

           <mesh>ParallelPlate_left</mesh>

           <type>Dirichlet</type>

           <parameter>p_in</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>ParallelPlate_right</mesh>

           <type>Dirichlet</type>

           <parameter>p_out</parameter>

         </boundary_condition>

       </boundary_conditions>

     </process_variable>

   </process_variables>

   <nonlinear_solvers>

     <nonlinear_solver>

       <name>basic_picard</name>

       <type>Picard</type>

       <max_iter>300</max_iter>

       <linear_solver>general_linear_solver</linear_solver>

     </nonlinear_solver>

   </nonlinear_solvers>

   <linear_solvers>

     <linear_solver>

       <name>general_linear_solver</name>

       <lis>-i cg -p jacobi -tol 1e-16 -maxiter 20000</lis>

       <eigen>

         <solver_type>BiCGSTAB</solver_type>

         <precon_type>ILUT</precon_type>

         <max_iteration_step>10000</max_iteration_step>

         <error_tolerance>1e-14</error_tolerance>

       </eigen>

       <petsc>

         <parameters>-ksp_type cg -pc_type bjacobi -ksp_atol 1e-10 -ksp_rtol 1e-8 -snes_type vinewtonssls -snes_linesearch_type l2 -snes_atol 1.e-8 -snes_rtol 1.e-8 -snes_max_it 1000 -snes_monitor</parameters>

       </petsc>

     </linear_solver>

   </linear_solvers>

   <test_definition>

     <vtkdiff>

       <regex>ParallelPlate_ts_[0-9]*_t_[0-9]*.000000.vtu</regex>

       <field>pressure_interpolated</field>

       <absolute_tolerance>1e-6</absolute_tolerance>

       <relative_tolerance>1e-10</relative_tolerance>

     </vtkdiff>

     <vtkdiff>

       <regex>ParallelPlate_ts_[0-9]*_t_[0-9]*.000000.vtu</regex>

       <field>liquid_velocity</field>

       <absolute_tolerance>1e-10</absolute_tolerance>

       <relative_tolerance>1e-16</relative_tolerance>

     </vtkdiff>

   </test_definition>

 </OpenGeoSysProject>