Gemma

Hi,

Just wondering if there are any plans to get around the issues of the requirement for multiple licenses to run parallel PEST with FEFLOW.  So far this has prevented us using PEST with our FEFLOW models, as without the option for running models in parallel, the PEST runtimes would be far too great.

I understand that we can't be supplied with infinite licences, but is there any way that the license manager could be set up to recognise when parallel PEST is being run and allow multiple licences to be temporarily activated for this purpose.  It is a shame not to be able to use it when it could significantly benefit model calibration, sensitivity and uncertainty analysis.

Thanks :)

Gemma

Thanks Zebra - we're just trying to set up a variably saturated model at the moment to see if it works better.

Gemma

Hi,

Has anyone else had problems downloading the Feflow manuals and Whitepapers from the Feflow website?

Cheers,

Gemma

Hi,

Just wondering if there is a way to simulate only saturated flow in a vertical 2D slice model which represents both confined and unconfined conditions?  I need the model to use the appropriate storage coefficient depending on whether conditions are confined or unconfined.  However, it seems that the model has to be made 3D to allow any unconfined conditions.  In this case though, then the settings do not really make sense for a vertical slice problem, as only the whole vertical slice can be changed to phreatic. 

Would it work better to use a variably saturated set-up?

Thanks!

Gemma 

Does anyone have any advice on this problem?!  :(

I'm simulating a contaminant plume and can't seem to avoid oscillations and negatives in the concentrations at the edges of the plume.  The mesh was set up to maintain a Peclet number of less than 1 given the dispersivity, so I don't think that refining the mesh will help.  I also ensured it had <5% obtuse triangles.  I've tried different upwinding techniques, but none of those remove the problem entirely either.  I've also tried a more gradual introduction of contaminant over time, but as soon as any contaminant mass enters the system then the negative values appear...

Would be really great if anyone can help!

Thanks,

Gemma

Alex,

thanks very much for your help,

Gemma

I'd also be interested in this one.  In particular, if you're only modelling the saturated flow system but there is an unsaturated interval at the top of the slice, then what is the best way to model the recharge to the water table?

Cheers

Hi,

Can anyone help?  I'm trying to simulate the injection of a known volume of water, with a known concentration of salinity (40 000 mg/l)  into the model.  I can therefore calculate the mass flux in g/d.  This suggests I should be able to use a 4th kind mass boundary condition, as the units of g/d agree with the units used here (mg/l x m^3/d).  I tried combining a 4th kind mass and a 4th kind flow boundary, so I had specified mass injected and volume injected, but the results of the budget analyser did not agree with the mass I was trying to inject.

The other suggestion I've had is to use a 4th kind flow boundary to inject the water and combine it with a 1st kind mass boundary (for concentration).  The problem here is that there is also significant lateral flow in the slice.  The budget analyser shows a mass flux in from both a 1st and a 4th kind boundary, but only the 1st kind boundaries were for mass, the 4th kind were for flow, so I don't really understand the output, or how to properly ensure that only the realistic mass flux can enter the model at the location of the injection well....? ! ?  ??? ???
Any help would be greatly appreciated as I'm getting pretty confused about how to do this!

Cheers very much,

Gemma

Hi,

Does anyone know the best way of representing time-variant recharge of fresh-water (0 mg/l) into an aquifer that is originally brackish to saline ( up to 5000 mg/l)?  Is it best to use injection wells to supply the recharge?  The recharge occurs as individual high recharge events, between which there is zero recharge.  If I use injection wells then how do I specify that the concentration of the water going in is 0 mg/l, rather than saline? 

Cheers,

Gemma ???

I'm having problems changing the colours of individual components of the model results such as particle path lines and the body of model, in the 3D viewer in the postprocessor.  I can only seem to change the colour of everything at once to the same colour.  I'd be grateful for any help with this problem.