Heat flux for multi-layered well (4th kind BC) is not distributed among slices

Hello,

I tried to model a multi-layered well with an given energy extraction (J/d) for some adjacent slices but it doesn't work: using the budget analyser, I found that the complete flux is extracted from the top slice only.

I carried out the following steps:
- activated the well bore condition in the specific option settings,
- choose Point Add-ins for the location of the well,
- type in the flux (J/d) for the first slice (as heat transport 4th kind BC),
- assigned zero flux for adjacent slices.

Is there anything I am missing?  Or are multi-layered wells not possible for heat transport?

Thank you for your help!

Hey,

I haven't used the budget analyzer for heat fluxes, but what you described sounds familiar from flow budgets. As far as I know, FeFlow calculates flows into a multi-layer well based on the layers' transmissivities, but only reports the flow total in the water budget at the node where a BC value <> 0 was specified. During the simulation, however, that total is spread along the well segment, so that ALL BC nodes along the well receive some portion of the total flow. Can someone confirm that??? It is confusing though ...

Chris.

Thanks for your reply.  However, my problem is a bit different, and I should perhaps clarify:

Not only are the slices below the top slice shown to have zero flux across the BC in the budget analyser, but it is also clearly visible from the temperature visualisation that there is no cooling around the well in those slices.  That is, heat is definitely extracted from the top slice only.

Any ideas what I may have done wrong?

Regards,
Frank

Unfortunately the multi-layer well does not add a one-dimensional element for the heat flux (it only creates the connection between the nodes for the flow simulation). So you should better use a 'Discrete Feature Element' for simulating the borehole in case of heat transport.