why this error occurred: Singular Matrix in Chemical Solver, STOP

[Sue]

I created a model to simulate the movement of heavy metals in polluted soil after rainfall. But there was an error:  Singular Matrix in Chemical Solver, STOP

The picture below is the initial water and boundary water information in my model.

Please tell me know how to make it.

[Alison]

This is a generic TOUGHREACT error that indicates a poorly defined chemical system.  Its hard for me to speculate about the exact reason you are seeing this.  If you would like to send your SIM file to tech@rockware.com, we can take a look at it to see if anything stands out to us!

 

Best Regards,

Alison

[Sue]

19 hours ago, Alison said:

This is a generic TOUGHREACT error that indicates a poorly defined chemical system.  Its hard for me to speculate about the exact reason you are seeing this.  If you would like to send your SIM file to tech@rockware.com, we can take a look at it to see if anything stands out to us!

 

Best Regards,

Alison

Here is the SIM file,test.simhope you can check out what goes wrong.

Thanks a lot!

[Alison]

The problem is that you have no zones assigned to cells 2 through 6.  You need to assign at least an Initial Water Zone to each cell in the model.

 

Best Regards,

Alison

 

[Sue]

On 4/30/2021 at 4:28 AM, Alison said:

Alison

Thanks，Alison

 

There is another problem: If I give a solute concentration in pore water and distribution coefficient Kd1,  when the calculation finished, take the save file as the initial condition for the next calculation.

 

• When import the save file, do it inherit the solutes mass adsorbed in the solid? or just inherit the solute concentration in pore water？
• Can these solutes adsorbed in the solid be desorbed?
• How to simulate adsorption and desorption，by set surface adsorption zone or liner Kd zone？I can not find where to set surface adsorption zone.

[Alison]

I think that you will probably need to use the Surface Complexation tools in TOUGHREACT v2 or v3.32 to do what you are looking for, as I don't think the Kd zones will allow mass to be desorbed.  PetraSim does include some support for TOUGHREACT v2 and v3.32, but does not include support in the interface for Surface Complexation.  You would need to acquire the newer simulator through LBL and you would need to make modifications to the input files created by PetraSim to add Surface Complexation zones.

 

If you own these newer simulators and would like additional information about using them with PetraSim, please contact me directly at alison@rockware.com