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Transport of Diluted Species and Darcy's Law

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Hello,

I've been working on a diffusion-advection model which uses a transport of diluted species module and I am using the velocity field from a Darcy's law module as the convective term via the transport properties. This is done as there is no multiphysics coupling between TDS and Darcy's law.

The simulation uses an exponentially decaying influx of diluted species which is completely disabled by an event changing a coefficient from 1 to 0 at a given time. However, in the simulation, the mass of diluted species accumulates exponentially across the domain over the whole timeframe.

Bare in mind that the multiphysics coupling of TDS and Brinkman equations and the running of the simulation with convection disabled yields expected results without the issues described.

Is this a known issue when using convection?


1 Reply Last Post 9 nov 2021, 05:46 GMT-5

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Posted: 2 years ago 9 nov 2021, 05:46 GMT-5

In case anyone sees this, an update, making the mesh finer from coarsest to coarser worsened this, causing the total mass of dulted species in the system to increase by a factor of over a trillion.

In case anyone sees this, an update, making the mesh finer from coarsest to coarser worsened this, causing the total mass of dulted species in the system to increase by a factor of over a trillion.

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