Denim Umeshkumar Anajwala

Hard to tell from the description, but in case the river in reality has a significant clogging layer (and is infiltrating), a switch to a Fluid-transfer BC for the river might be a good idea.

Please try to select Edges rather than Join Edges. With this, it should work.

Hi.

I think it can be done with an IFM plug-in. The ID/labels for observation points are known before the simulation and can be stored in a TXT file. Then, the TXT file can be read by the plug-in, and store the list on a C++ vector. Then, use this IFM command to get the head value at the desired observation points: http://www.feflow.info/html/help/HTMLDocuments/ifm/ifm_api/IfmGetFlowValueOfObsIdAtCurrentTime.htm

Finally, export the output to a TXT file and merge later with X,Y,Z, reference head values. 

Hi.

Indeed, there was a bug. I updated from FEFLOW 7.3 to 7.4 last Tuesday. The right click on plug-in and "edit" did nothing. I decided to uninstall FEFLOW 7.4 and reinstall 7.3.

By going back to 7.3 I recovered the plug-in functionalities but it was a bit complicate. Somehow, Windows 7 removed my user account write access to TEMP folder. So, I couldn't  install or uninstall anything on Windows. The solution to this issue is explained in Windows support: https://support.microsoft.com/en-us/kb/2000547

Is it worth to install the update 4 or stay with the stable version (update 3)?

Thanks in advance.

Another option would be using a stored selection as the plotting target: You can select all elements (in a layer or in 3D) where h<elevation (this is the case above the water table) via 'Select by Expression', then store the selection and plot the isolines onto this selection by clicking it in the'Selections' panel before double-clicking to show hydraulic head.

In FEFLOW, the simulation is done in 3D (so it's not a collection of 2D models for the aquifers and aquitards). Thus the influence of the water level in one aquifer onto another aquifer depends on the properties of the layer in between. If you don't see any influence, the aquitard in between probably has a very low hydraulic conductivity.

1. You can set up an elemental or nodal expression, dividing the resulting Darcy velocity by the porosity.
2. FEFLOW does not use any dry cells. In the dry layers in phreatic mode, the hydraulic conductivity is reduced linearly with saturation of the element, but the element stays part of the simulation. Thus recharge is still also added on top of the model (into slice 1). This will lead to a vertical gradient in hydraulic head, as recharge has to be routed from the model top to the water level. The phreatic approch is a generally very stable solution for regional model with a predominantly horizontal groundwater flow. In more local situations, or situations with vertical flow dominating, I'd recommend to rather use a variably saturated/unsaturated approach applying Richards' equation.

The effective (horizontal) conductivity at a slice in between an aquifer and an aquitard is a volume-averaged mean.

An undefined hydraulic head points towards some quite severe numerical problems in the model. I highly recommend to contact our user support (mike.de@dhigroup.com) and provide them with the model for checking.

For discrete structures, such as faults, you can use FEFLOW's feature 'Discrete Features'. Have a look at the manual and/or help system for details!