Missing zero-order decay for the solid phase in GWE

[cneyens]

Chapter 10 of the Supplemental Technical Information for MODFLOW 6 (v6.6.0) describes the Groundwater Energy Model. Equations 10-1 to 10-3 show that zero-order decay for both the solid and aqueous phase can be simulated. This is also explicitly stated in the accompanying text. In the IO guide however, only aqueous decay is described, which is indeed only used for decay in the aqueous phase and not both the aqueous and solid phase (as can be be verified by comparing to an analytical solution).

Is the solid-phase zero-order decay input missing from the input guide or is this functionality not implemented yet (in contrast to what's described in the Supplemental guide)?

[emorway-usgs]

Thanks for bringing this to our attention, @cneyens. We're taking a closer look. When you say, "as can be verified by comparing to an analytical solution," did you set up a test?

[cneyens]

I made a single-cell GWE model with only zero-order production as heat source (see attached notebook).

gwe_decay.zip

[emorway-usgs]

Working on fix, @cneyens. Thanks for the example, it'll definitely help ensure the code is working properly.

[emorway-usgs]

Thanks again for pointing out this issue, @cneyens, we appreciate your patience as we worked on the fix in #2155. The next nightly build should be good to go.