Hi to all,
I would like to define Temperature BC at node in transient model. This temperature should be 5 K higher than the temperature at some other node.
For example: Node Nr. 111 lies inside an area, where is the GW temperature seasonally changing. At node of my interest, I would like to have temperature 5K higher, than at node Nr. 111 during the whole simulation period. In Expression Editor this...  Current = T(111)@(Time)  ... does not work.

Is there any way how to simple define this?
If you know the temperature of the other node throughout the period via a boundary condition you could set up two time series, one for each of the nodes.

I think this should work?:

Current_new = Current(No_n(111)) + 5000

Where No_n is the node number and Current is the property/BC.
Hi,
thanks for the answer. This should work, of course, as well as I can create second time serie according to the recorded temperatures on the known node, but what I would like to do, is set the Temperature BC on any node just using editor in transient mode. So the temperature on the node (111) is changing during the time. If I write: Current = T(111)@(Time) + 5, the temperature of my node is in the initial time really 5 K higher, but in next time steps this difference is not preserved. There is no change in simulation, if I write: Current = T(111)@(Time) + 5 or if i write: Current = T(111)@(0) + 5. So the question should probably be: can I define the Time as variable?
Thanks!
Ahh, I understand the problem now. I was not aware that it wouldn't update every timestep. If this difference is not preserved, you should consider writing a plug-in through the FEFLOW API.

Here's what I'd do:

Pre-timestep:

IfmSetBcHeatValueAtCurrentTime(pDoc, your_node_plus_5000, IfmGetBCHeatValue(pDoc, your_node) + 5000)

To note: the node index starts at 0 instead of 1, so add 1 to your node to reference the right node.
The expressions can currently only be used to assign values to a BC, not as expressions that are evaluated during run time. This is only possible for the recharge and source/sink parameters (flow and transport). If this is about an open-loop geothermal system, where the injection temperature is 5K different from the extraction temperature, the FEFLOW support team can provide you with a free plug-in achieving this (OpenLoop). If it is nodes other than pumping wells, you'd have to program your own plug-in or python script.
any way to directly import precipitation to feflow and the change recharge according to each zones based on some percentage of precipitation?

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