andrewdnolan / thermal-structure

Thermomechanically coupled surging experiments with Elmer/Ice
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Volumetric Heat Source to Mass Heat Source #2

Open andrewdnolan opened 2 years ago

andrewdnolan commented 2 years ago

In the surface boundary process function (Surface_Processes in src/elmer_UDF/SurfaceBoundary.f90) I calculate the volumetric heat source (Q_lat) based on Eqn. (9) from Wilson and Flowers (2013): https://github.com/andrewdnolan/thermal-structure/blob/a6041dbb8da42aa67f6c5ae5575866a24d9e35ac/src/elmer_UDF/SurfaceBoundary.f90#L528

My initial attempts to prescribe Q_lat as prescribing a volumetric source (J/m^3) along the surface boundary conflicted with the Dirichlet B.C. based on air temp and in-effect Q_lat was ignored by Elmer. Previously as solution this problem, I prescribed Q_lat as a volumetric heat source one node below the surface, which worked but was nonphysical.

Instead I've edited the code to convert Q_lat to a mass heat source (J/kg) which can be used to augment the Dirichlet B.C. for enthalpy along the free surface. See Eqn. (6) from Licciulli et al. (2019) for an example of this approach.

I'm unsure what density should I use to convert Q_lat from a volumetric (J/m^3) to mass (J/kg) heat source. I'm currently just using the density of water:

https://github.com/andrewdnolan/thermal-structure/blob/a6041dbb8da42aa67f6c5ae5575866a24d9e35ac/src/elmer_UDF/SurfaceBoundary.f90#L550 but I'm maybe this should be surface density?