Why

[XiaoMao]

I downloaded the example from 

https://www.thunderheadeng.com/petrasim/petrasim-4-documentation/

Example Problem 1, Linear sorption and decay (EOS9).

 

I want to simulate that the low pH caused by CO2 dissolution transport in the domain.
Therefore, I modified the example problem 1

I set two Gas zones in the model.

CO2 partial pressure is zero in the first zone and it has been set all cells.

and then CO2 partial pressure is 10 in the second zone, and it has been set at middle one cell.

However, I got resutls like this,

low pH only occurs in the cell which is set high partial pressure and it did not move with groundwater flow.

Logically, low pH should migrate to the right. But it doesn't。

Is anyone can tell me the reason ?

 

you can find the sim file in the attachment.

Thank you so much.

 

 

treact_prob_1.sim

[XiaoMao]

My question is

Why low pH caused by carbon dioxide cannot move forward

 

[Alison]

I have been experimenting with your model and converted it to EOS3 so that I could add gas saturation to the model.  I was able to see the pH in the cell change by doing the following:

 

1.  Adding the gas phase to the model.  For example, initialize the model with 0.2 SG, or even just the cell with the high gas zone.

2.  Under TOUGHREACT | Solution parameters, make sure that NGAS1 is checked on.

[XiaoMao]

On 6/23/2020 at 5:08 PM, Alison said:

I have been experimenting with your model and converted it to EOS3 so that I could add gas saturation to the model.  I was able to see the pH in the cell change by doing the following:

 

1.  Adding the gas phase to the model.  For example, initialize the model with 0.2 SG, or even just the cell with the high gas zone.

2.  Under TOUGHREACT | Solution parameters, make sure that NGAS1 is checked on.

Ok

Thank you so much