Composition error: boundary condition implementation for incomp 2phase

[Yohanes Nuwara]

Dear all, 

I try to implement boundary conditions in an incompressible 2 phase (oil-water) program, "computeLorenzSPE10". 

I have set up the boundary conditions:

bc = fluxside([], G, 'FRONT', 0);

bc = fluxside(bc, G, 'BACK', 10);

bc = fluxside(bc, G, 'LEFT', -5);

bc = pside(bc, G, 'RIGHT', 100);

And added 'bc' to the "incompTPFA" and "implicitTransport"

x  = incompTPFA(x, G, hT, fluid, 'bc', bc, 'wells', W);

x  = implicitTransport(x, G, dT, rock, fluid, 'bc', bc, 'wells', W);

I got the following error:

error: Injection composition incompatible with existing source terms

Do I have something missing from my code? 

Meanwhile, I have searched for any script in the "in2ph" folder inside the "book" module, I haven't found an example that implements boundary cond. 

The attached link is my full source code. I'd be glad if you could help me out, thanks!

Best, 

Yohanes

[Øystein S. Klemetsdal]

Dear Yohanes,

MRST uses single-point upwind discretization for the fluxes, so you need to also specify the saturation at the boundaries, e.g.,

bc = fluxside([], G, 'FRONT', 0, 'sat', [sw, so]);

Note that this is required for all boundaries, but technically only used for inflow.

Cheers,

-Øystein Klemetsdal

[Yohanes Nuwara]

Hi Oystein, 

Thanks for your solution, it worked. I want to implement the following boundaries to my case:

# Boundary conditions 

bc = [];

bc = pside([], G, 'FRONT', 100, 'sat', [1 0]);

bc = fluxside(bc, G, 'BACK', -5*stb/day, 'sat', [1 0]);

bc = pside(bc, G, 'LEFT', 100, 'sat', [1 0]);

bc = fluxside(bc, G, 'RIGHT', 10*stb/day, 'sat', [1 0]);

I observed that these boundaries result in an error saying:

error: MRST does not support injection and production in same cell

However, if some boundaries are passed, for example, only left-right, front-back, or back-left, it successfully runs without the error. For some other boundaries; back-right or front-right, it also gives the same error. 

I wonder why? 

Cheers, 

Yohanes 

[Olav Møyner]

Hi,

These solvers do not support multiple boundary conditions in the same cell, which will happen on the cells on the corners of the model. It may be difficult to impose both a constant volumetric depletion/injection and a specific pressure for incompressible flow. Some of the newer solvers do not have this limitation, but I would just start with fewer boundary conditions to get it running (e.g. just the right and left conditions)

Best regards,

Olav

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From: sinte...@googlegroups.com <sinte...@googlegroups.com> on behalf of Yohanes Nuwara <ign.nu...@gmail.com>
Sent: Saturday, March 13, 2021 5:09
To: MRST-users: The Matlab Reservoir Simulation Toolbox User Group <sinte...@googlegroups.com>
Subject: [MRST Users] Re: Composition error: boundary condition implementation for incomp 2phase

 

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