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hi

	 Our team are working at a project on seawater intrusion in China, and
its the time to choose a proper software. Feflow, as our first choise,
is definitely the  most powerful and reliable one but I still have
some wonders may be you can help me with.

	 Our project this time including a information system (manage the sea
water data, developed through the ARCgis engine) and we want to add
several simulation models in to this system, I mean after we establish
the simulation models, we want to use feflow to do the calculations in
our integrated user interface rather than in feflow itself, and of
course the results have to be given in our system. As I know there is
no SDK in 5.3 or eailer.

You should find find all you need at this web site:

http://www.feflow.info/26.html

*Pete *
www.aquageo.us


Marielena Lucen wrote:
>
> Hi giovanni
>
> Thank you but i do not have de cd program, so if you are so afable and
> send
> me the exercise I will be very thankful with you
>
> Bye
> Malena Lucen
>
> 2009/2/18 Giovanni Firmani <g.firmani@...
> <mailto:g.firmani%40gmail.com>>
>
> > In the program folder you can find examples and exercises:
> >
> > C:\Program Files\WASY\FEFLOW 5.3\demo
> >
> > while in the Installing dvd you can find all the manuals and in
> > particular the tutorial for the demo example exercise:
> >
> > E:\doc\demo_exercise.pdf
> >
> > there is also a Spanish version in my dvd
> >
> > E:\doc\demo_exercise_espanol.pdf
> >
> > Ciao
> > gio
> >
> >
> > On Thu, Feb 19, 2009 at 11:43 AM, marielenalucen
> <malenalucen@...
> <mailto:malenalucen%40gmail.com><malenalucen%40gmail.com>>
> > wrote:
> > > hi everybody
> > >
> > > i desperate need a tutorial or some applications or examples using
> > > feflow, please if some have a file in pdf or word about this please
> > > send it to malenalucen@... <mailto:malenalucen%40gmail.com>
> <malenalucen%40gmail.com>
> > >
> > > Thank you
> > >
> > > Marielena Lucen
> > > Hydraulic Engineer
> > > Peru

Hi giovanni

Thank you but i do not have de cd program, so if you are so afable and send
me the exercise I will be very thankful with you

Bye
Malena Lucen


2009/2/18 Giovanni Firmani <g.firmani@...>

>   In the program folder you can find examples and exercises:
>
> C:\Program Files\WASY\FEFLOW 5.3\demo
>
> while in the Installing dvd you can find all the manuals and in
> particular the tutorial for the demo example exercise:
>
> E:\doc\demo_exercise.pdf
>
> there is also a Spanish version in my dvd
>
> E:\doc\demo_exercise_espanol.pdf
>
> Ciao
> gio
>
>
> On Thu, Feb 19, 2009 at 11:43 AM, marielenalucen
<malenalucen@...<malenalucen%40gmail.com>>
> wrote:
> > hi everybody
> >
> > i desperate need a tutorial or some applications or examples using
> > feflow, please if some have a file in pdf or word about this please
> > send it to malenalucen@... <malenalucen%40gmail.com>
> >
> > Thank you
> >
> > Marielena Lucen
> > Hydraulic Engineer
> > Peru

In the program folder you can find examples and exercises:

C:\Program Files\WASY\FEFLOW 5.3\demo

while in the Installing dvd you can find all the manuals and in
particular the tutorial for the demo example exercise:

E:\doc\demo_exercise.pdf

there is also a Spanish version in my dvd

E:\doc\demo_exercise_espanol.pdf

Ciao
gio


On Thu, Feb 19, 2009 at 11:43 AM, marielenalucen <malenalucen@...> wrote:
> hi everybody
>
> i desperate need a tutorial or some applications or examples using
> feflow, please if some have a file in pdf or word about this please
> send it to malenalucen@...
>
> Thank you
>
> Marielena Lucen
> Hydraulic Engineer
> Peru

hi everybody

i desperate need a tutorial or some applications or examples using
feflow, please if some have a file in pdf or word about this please
send it to malenalucen@...

Thank you

Marielena Lucen
Hydraulic Engineer
Peru

Thanks Pete.

You are right, I figured out that Feflow interpolates the values at
t=0 and t=730. As you said the only way to switch off the 1st boundary
condition is to use the constrains. I my case it was easy cause I was
simulating a time variant seepage condition (some horizontal holes
built in different periods) and from 0 to 729 I assumed a fake
head=999 with the constrain in the maximum flow (=0).

Thank you very much. I had a confimation I have done the right thing though !

Gio


On Sun, Feb 15, 2009 at 3:18 AM, Pete Sinton <psinton@...> wrote:
> Hi Gio,
>
> I searched my notes and manuals about this and came up with nothing.  In
> all the examples I've seen, the first time is always zero, and I have
> been in habit of setting up my power functions this way for a long
> time.  I don't remember what FEFLOW assumes for a situation like you
> describe, but my guess is that it will either use the value at time 730
> for the value at time 0 or will set the value to 0 at time 0 and
> interpolate between time 0 and time 730.
>
> There is no direct way of "turning off" (deactivating) a boundary
> condition  (BC) within a single feflow model, unless you use the
> SwitchBC module which you'd have to get from WASY.  In some cases a BC
> node can be deactivated using BC constraints, but this will not always
> work (especially as the model complexity or number of such constraints
> increases).  You can also deactivate a BC by using two feflow models,
> one that simulates a portion of time without the BC, and one set up with
> it.  The first model would be used to initialize the second.  Run a
> model from zero to 730 without the BC, use the result to initialize a
> second model that has the time varying BC.
>
> Pete

Hi Gio,

I searched my notes and manuals about this and came up with nothing.  In
all the examples I've seen, the first time is always zero, and I have
been in habit of setting up my power functions this way for a long
time.  I don't remember what FEFLOW assumes for a situation like you
describe, but my guess is that it will either use the value at time 730
for the value at time 0 or will set the value to 0 at time 0 and
interpolate between time 0 and time 730.

There is no direct way of "turning off" (deactivating) a boundary
condition  (BC) within a single feflow model, unless you use the
SwitchBC module which you'd have to get from WASY.  In some cases a BC
node can be deactivated using BC constraints, but this will not always
work (especially as the model complexity or number of such constraints
increases).  You can also deactivate a BC by using two feflow models,
one that simulates a portion of time without the BC, and one set up with
it.  The first model would be used to initialize the second.  Run a
model from zero to 730 without the BC, use the result to initialize a
second model that has the time varying BC.

Pete


Giovanni Firmani wrote:
>
> Pete,
> I have a terrible doubt now. If I define a power function (for a head
> boundary condition for example) file like the following one
>
> !
> ! t [d] fvalue
> !---------------------
> 730 334
> 1460 334
>
> does it mean that the head boundary condition is off between 0 and
> 730? Running the model I noticed that is not like that but if I do not
> want the boundary condition ON I have to use a fake head and a
> constrain that is able to disable it between 0 and 730.
>
> Giovanni
>
> On Sun, Feb 8, 2009 at 12:59 PM, Pete Sinton <psinton@...
> <mailto:psinton%40aquageo.us>> wrote:
> > Hi Gio,
> >
> > Yes, that works. I find it convoluted and cumbersome, so I resort to
> > bypassing feflow's interface. I know I will get what I want.
> >
> > Glad to hear you solved the problem
> >
> > Cheers
> >
> > --
> >
> > Pete Sinton
> >
> > Principal Hydrogeologist
> >
> > AquaGeo, Ltd.
> >
> > 11560 Penny Rd
> >
> > Conifer CO 80433
> >
> > Cell 720.841.5526
> >
> > Phone 303.838.7863
> >
> > psinton@... <mailto:psinton%40aquageo.us>
> >
> > www.aquageo.us
> >
> > This e-mail together with any attachments is confidential and may be the
> > subject of legal privilege. If you are not the intended recipient,
> you are
> > not permitted to print, copy, disclose or use the content or
> attachments in
> > any way. AquaGeo, Ltd. respectfully requests that you reply to this
> e-mail
> > and delete this message. AquaGeo, Ltd. accepts no responsibility for
> changes
> > made to this e-mail or any attachments after transmission from
> AquaGeo, Ltd.
> > Thank you.
> >
> > Thanks Pete,
> >
> > As workaround I manage to generate some input files: one for the
> > "power functions" and one for the "time variant ID". For the
> > generation of the file, I have temporary assigned the boundary
> > conditions as the time-constant and the I exported them as ASCII file
> > that I modified and imported again to simulate time-variant boundary
> > conditions.
> > However, I noticed that importing an external file using the command
> > "database" is quite tricky. Following the procedure described in this
> > forum:
> >
> > http://feflow.info/forum/index.php/topic,446.msg1332.html#msg1332
> <http://feflow.info/forum/index.php/topic,446.msg1332.html#msg1332>
> >
> > I used the commands: Assign - database - Import Time-varying IDs -
> > Head BC/Seepage - Automatic regionalization.
> >
> > But I had to use 'Inverse
> > Distance Weighting' with only one neighboring point as the
> > regionalization method for getting the exact numbers I wanted for each
> > node.
> >
> > In theory the command "interpolate" the data. To avoid the
> > interpolation I used "

Pete,
I have a terrible doubt now. If I define a power function (for a head
boundary condition for example)  file like the following one

!
!  t [d]      fvalue
!---------------------
730        334
1460      334

does it mean that the head boundary condition is off between 0 and
730? Running the model I noticed that is not like that but if I do not
want the boundary condition ON I have to use a fake head and a
constrain that is able to disable it between 0 and 730.

Giovanni


On Sun, Feb 8, 2009 at 12:59 PM, Pete Sinton <psinton@...> wrote:
> Hi Gio,
>
> Yes, that works.  I find it convoluted and cumbersome, so I resort to
> bypassing feflow's interface.  I know I will get what I want.
>
> Glad to hear you solved the problem
>
> Cheers
>
> --
>
> Pete Sinton
>
> Principal Hydrogeologist
>
> AquaGeo, Ltd.
>
> 11560 Penny Rd
>
> Conifer CO 80433
>
> Cell 720.841.5526
>
> Phone 303.838.7863
>
> psinton@...
>
> www.aquageo.us
>
> This e-mail together with any attachments is confidential and may be the
> subject of legal privilege. If you are not the intended recipient, you are
> not permitted to print, copy, disclose or use the content or attachments in
> any way.  AquaGeo, Ltd. respectfully requests that you reply to this e-mail
> and delete this message. AquaGeo, Ltd. accepts no responsibility for changes
> made to this e-mail or any attachments after transmission from AquaGeo, Ltd.
> Thank you.
>
> Thanks Pete,
>
> As workaround I manage to generate some input files: one for the
> "power functions" and one for the "time variant ID". For the
> generation of the file, I have temporary assigned the boundary
> conditions as the time-constant and the I exported them as ASCII file
> that I modified and imported again to simulate time-variant boundary
> conditions.
> However, I noticed that importing an external file using the command
> "database" is quite tricky. Following the procedure described in this
> forum:
>
> http://feflow.info/forum/index.php/topic,446.msg1332.html#msg1332
>
> I used the commands: Assign - database - Import Time-varying IDs -
> Head BC/Seepage - Automatic regionalization.
>
> But I had to use 'Inverse
> Distance Weighting' with only one neighboring point as the
> regionalization method for getting the exact numbers I wanted for each
> node.
>
> In theory the command "interpolate" the data. To avoid the
> interpolation I used "
>

Thanks Pete,

As workaround I manage to generate some input files: one for the
"power functions" and one for the "time variant ID". For the
generation of the file, I have temporary assigned the boundary
conditions as the time-constant and the I exported them as ASCII file
that I modified and imported again to simulate time-variant boundary
conditions.
However, I noticed that importing an external file using the command
"database" is quite tricky. Following the procedure described in this
forum:

http://feflow.info/forum/index.php/topic,446.msg1332.html#msg1332

I used the commands: Assign - database - Import Time-varying IDs -
Head BC/Seepage - Automatic regionalization.But I had to use 'Inverse
Distance Weighting' with only one neighboring point as the
regionalization method for getting the exact numbers I wanted for each
node.


In theory the command "interpolate" the data. To avoid the
interpolation I used "

On Sun, Feb 8, 2009 at 12:43 AM, Pete Sinton <psinton@...> wrote:
> Hi Gio,
>
> I see your point.  There's no way around it but you can create the node
> and power lists outside of feflow and edit them into an ascii fem. I've
> done a lot of this; let me know if I can help.
>
> *Pete*
>
>
> Giovanni Firmani wrote:
>>
>> Pete,
>>
>> assigning a pressure condition or a head condition for feflow is
>> exactly the same. Let assume (as in my case) I have to model a
>> seepage, I would use h=z and p=0. If the seepage boundary changes with
>> time I would need a different power function for each node (as there
>> is a different head for each node). But as p=0 is the same for each
>> node it would be easier to use only one power function for all the
>> nodes. This is the reason why I was wondering if it is possible to use
>> a power function for a pressure boundary condition
>>
>> Ciao
>> Gio
>>
>> On Sat, Feb 7, 2009 at 12:34 AM, Pete Sinton <psinton@...
>> <mailto:psinton%40aquageo.us>> wrote:
>> > Odd, but you are right. On my first attempt, it seemed to work, but when
>> > I looked at the node with the inspector, it indicated the boundary
>> > condition was a HEAD node, not pressure.
>> >
>> > It does not really matter though, because the help file indicates
>> > (consistent with physics) that feflow converts the pressure to total
>> > head anyway using equation h = p/(rho*g) + node_elevation. So if you
>> > input a pressure or a head, feflow ultimately operates on head. You can
>> > input a total head for the vadose zone and it will understand that the
>> > fixed head is above the water table if the head you input is smaller
>> > than the elevation of the node. Such nodes should probably only be set
>> > in a variable-saturation model, not confined or phreatic.
>> >
>> > *Pete Sinton*
>> >
>> > www.aquageo.us
>> >
>> >
>> > Giovanni Firmani wrote:
>> >>
>> >> I tried that
>> >>
>> >> When I use options->pressure instead of head I cannot define any
>> >> time-variant function. It seems that is not possible to assign a time
>> >> variant function for the presure :(
>> >>
>> >> Giovanni
>> >>
>> >> On Fri, Feb 6, 2009 at 3:56 AM, Pete Sinton <psinton@...
>> <mailto:psinton%40aquageo.us>
>> >> <mailto:psinton%40aquageo.us>> wrote:
>> >> > yes - it is done the same you would do with head, but select
>> pressure as
>> >> > the variable of choice. under the mesh inspector, set the light
>> >> > blue button to "options", then select "head (1st kind)" button.
>> Select
>> >> > pressure as the variable of choice.
>> >> >
>> >> > *Pete Sinton*
>> >> >
>> >> > www.aquageo.us
>> >> >
>> >> >
>> >> >
>> >> > Giovanni Firmani wrote:
>> >> >>
>> >> >> Is it possible to set up a time-varying function for the pressure
>> >> >> instead of the head when dealing with unsaturated problems?
>> >> >>
>> >> >> Regards
>> >> >>
>> >> >> Giovanni

Hi Gio,

I see your point.  There's no way around it but you can create the node
and power lists outside of feflow and edit them into an ascii fem. I've
done a lot of this; let me know if I can help.

*Pete*


Giovanni Firmani wrote:
>
> Pete,
>
> assigning a pressure condition or a head condition for feflow is
> exactly the same. Let assume (as in my case) I have to model a
> seepage, I would use h=z and p=0. If the seepage boundary changes with
> time I would need a different power function for each node (as there
> is a different head for each node). But as p=0 is the same for each
> node it would be easier to use only one power function for all the
> nodes. This is the reason why I was wondering if it is possible to use
> a power function for a pressure boundary condition
>
> Ciao
> Gio
>
> On Sat, Feb 7, 2009 at 12:34 AM, Pete Sinton <psinton@...
> <mailto:psinton%40aquageo.us>> wrote:
> > Odd, but you are right. On my first attempt, it seemed to work, but when
> > I looked at the node with the inspector, it indicated the boundary
> > condition was a HEAD node, not pressure.
> >
> > It does not really matter though, because the help file indicates
> > (consistent with physics) that feflow converts the pressure to total
> > head anyway using equation h = p/(rho*g) + node_elevation. So if you
> > input a pressure or a head, feflow ultimately operates on head. You can
> > input a total head for the vadose zone and it will understand that the
> > fixed head is above the water table if the head you input is smaller
> > than the elevation of the node. Such nodes should probably only be set
> > in a variable-saturation model, not confined or phreatic.
> >
> > *Pete Sinton*
> >
> > www.aquageo.us
> >
> >
> > Giovanni Firmani wrote:
> >>
> >> I tried that
> >>
> >> When I use options->pressure instead of head I cannot define any
> >> time-variant function. It seems that is not possible to assign a time
> >> variant function for the presure :(
> >>
> >> Giovanni
> >>
> >> On Fri, Feb 6, 2009 at 3:56 AM, Pete Sinton <psinton@...
> <mailto:psinton%40aquageo.us>
> >> <mailto:psinton%40aquageo.us>> wrote:
> >> > yes - it is done the same you would do with head, but select
> pressure as
> >> > the variable of choice. under the mesh inspector, set the light
> >> > blue button to "options", then select "head (1st kind)" button.
> Select
> >> > pressure as the variable of choice.
> >> >
> >> > *Pete Sinton*
> >> >
> >> > www.aquageo.us
> >> >
> >> >
> >> >
> >> > Giovanni Firmani wrote:
> >> >>
> >> >> Is it possible to set up a time-varying function for the pressure
> >> >> instead of the head when dealing with unsaturated problems?
> >> >>
> >> >> Regards
> >> >>
> >> >> Giovanni
>
>


[Non-text portions of this message have been removed]

Pete,

assigning a pressure condition or a head condition for feflow is
exactly the same. Let assume (as in my case) I have to model a
seepage, I would use h=z and p=0. If the seepage boundary changes with
time I would need a different power function for each node (as there
is a different head for each node). But as p=0 is the same for each
node it would be easier to use only one power function for all the
nodes. This is the reason why I was wondering if it is possible to use
a power function for a pressure boundary condition

Ciao
Gio


On Sat, Feb 7, 2009 at 12:34 AM, Pete Sinton <psinton@...> wrote:
> Odd, but you are right. On my first attempt, it seemed to work, but when
> I looked at the node with the inspector, it indicated the boundary
> condition was a HEAD node, not pressure.
>
> It does not really matter though, because the help file indicates
> (consistent with physics) that feflow converts the pressure to total
> head anyway using equation h = p/(rho*g) + node_elevation.  So if you
> input a pressure or a head, feflow ultimately operates on head.  You can
> input a total head for the vadose zone and it will understand that the
> fixed head is above the water table if the head you input is smaller
> than the elevation of the node.  Such nodes should probably only be set
> in a variable-saturation model, not confined or phreatic.
>
> *Pete Sinton*
>
> www.aquageo.us
>
>
> Giovanni Firmani wrote:
>>
>> I tried that
>>
>> When I use options->pressure instead of head I cannot define any
>> time-variant function. It seems that is not possible to assign a time
>> variant function for the presure :(
>>
>> Giovanni
>>
>> On Fri, Feb 6, 2009 at 3:56 AM, Pete Sinton <psinton@...
>> <mailto:psinton%40aquageo.us>> wrote:
>> > yes - it is done the same you would do with head, but select pressure as
>> > the variable of choice. under the mesh inspector, set the light
>> > blue button to "options", then select "head (1st kind)" button. Select
>> > pressure as the variable of choice.
>> >
>> > *Pete Sinton*
>> >
>> > www.aquageo.us
>> >
>> >
>> >
>> > Giovanni Firmani wrote:
>> >>
>> >> Is it possible to set up a time-varying function for the pressure
>> >> instead of the head when dealing with unsaturated problems?
>> >>
>> >> Regards
>> >>
>> >> Giovanni

Odd, but you are right. On my first attempt, it seemed to work, but when
I looked at the node with the inspector, it indicated the boundary
condition was a HEAD node, not pressure.

It does not really matter though, because the help file indicates
(consistent with physics) that feflow converts the pressure to total
head anyway using equation h = p/(rho*g) + node_elevation.  So if you
input a pressure or a head, feflow ultimately operates on head.  You can
input a total head for the vadose zone and it will understand that the
fixed head is above the water table if the head you input is smaller
than the elevation of the node.  Such nodes should probably only be set
in a variable-saturation model, not confined or phreatic.

*Pete Sinton*

www.aquageo.us


Giovanni Firmani wrote:
>
> I tried that
>
> When I use options->pressure instead of head I cannot define any
> time-variant function. It seems that is not possible to assign a time
> variant function for the presure :(
>
> Giovanni
>
> On Fri, Feb 6, 2009 at 3:56 AM, Pete Sinton <psinton@...
> <mailto:psinton%40aquageo.us>> wrote:
> > yes - it is done the same you would do with head, but select pressure as
> > the variable of choice. under the mesh inspector, set the light
> > blue button to "options", then select "head (1st kind)" button. Select
> > pressure as the variable of choice.
> >
> > *Pete Sinton*
> >
> > www.aquageo.us
> >
> >
> >
> > Giovanni Firmani wrote:
> >>
> >> Is it possible to set up a time-varying function for the pressure
> >> instead of the head when dealing with unsaturated problems?
> >>
> >> Regards
> >>
> >> Giovanni

I tried that

When I use options->pressure instead of head I cannot define any
time-variant function. It seems that is not possible to assign a time
variant function for the presure :(

Giovanni

On Fri, Feb 6, 2009 at 3:56 AM, Pete Sinton <psinton@...> wrote:
> yes - it is done the same you would do with head, but select pressure as
> the variable of choice.  under the mesh inspector, set the light
> blue button to "options", then select "head (1st kind)" button.  Select
> pressure as the variable of choice.
>
> *Pete Sinton*
>
> www.aquageo.us
>
>
>
> Giovanni Firmani wrote:
>>
>> Is it possible to set up a time-varying function for the pressure
>> instead of the head when dealing with unsaturated problems?
>>
>> Regards
>>
>> Giovanni

yes - it is done the same you would do with head, but select pressure as
the variable of choice.  under the mesh inspector, set the light
blue button to "options", then select "head (1st kind)" button.  Select
pressure as the variable of choice.

*Pete Sinton*

www.aquageo.us



Giovanni Firmani wrote:
>
> Is it possible to set up a time-varying function for the pressure
> instead of the head when dealing with unsaturated problems?
>
> Regards
>
> Giovanni

Is it possible to set up a time-varying function for the pressure
instead of the head when dealing with unsaturated problems?

Regards

Giovanni

It is surprising that some spam messages are being circulated in the
group for past few days, though the group is moderated. I am trying to
look into the problem.

Peter,

I am not sure about oscillation. However, coarse discretization,
especially in the vertical, definitely causes numerical dispersion
in FEFLOW - at times, involving large errors.

Cheers,

Shlomo Orr.



   ----- Original Message -----
   From: peter.schaetzl
   To: feflow@...
   Sent: Wednesday, November 26, 2008 1:47 AM
   Subject: [feflow] Re: too much dispersion within an unsaturated flow and mass
transport model


   Monica,

   A too coarse discretization would typically lead to oscillations
   rather than high numerical dispersion. So please check whether your
   dispersivity values are realistic and whether you have turned on an
   upwind method (in Temporal&Control data). Upwind methods stabilize the
   solution on too coarse meshes, but depending on the method used a high
   amount of artificial dispersion might be added.

   Hope this helps

   Peter
   FEFLOW Support Team

Here's one paper:
http://www.imwa.info/docs/imwa_2008/IMWA2008_190_Ruehaak.pdf

and another one:
ftp://ftp1.wasy.de/outgoing/IAHR2008_Diersch_et_al_DHI-WASY-HeatPipe-fina.pdf
(this link will only be valid for a few days).

Open-loop systems are very frequently modelled with FEFLOW, but the
engineers designing these systems don't publish very much.

Cheers,
Peter
FEFLOW Support

I forgot something in my last post:
For open-loop systems, you often would like to link the injection
temperature to the abstraction temperature by applying a constant or
time-varying temperature differential. As this is not possible in the
standard user interface of FEFLOW, DHI-WASY provides a module for the
FEFLOW programming interface IFM for this, called SimpleOpenLoop. If
you need this, just email to the FEFLOW support (support@...).

Peter

Monica,

A too coarse discretization would typically lead to oscillations
rather than high numerical dispersion. So please check whether your
dispersivity values are realistic and whether you have turned on an
upwind method (in Temporal&Control data). Upwind methods stabilize the
solution on too coarse meshes, but depending on the method used a high
amount of artificial dispersion might be added.

Hope this helps

Peter
FEFLOW Support Team

Monica,

Among other things, FEFLOW (like some other models) suffers from
a large numerical dispersion. The simplest solution is to subdivide the
domain into many smaller ones (in your case, many layers).

Good luck,

Shlomo Orr.


   ----- Original Message -----
   From: mirunache
   To: feflow@...
   Sent: Tuesday, November 25, 2008 5:59 AM
   Subject: [feflow] too much dispersion within an unsaturated flow and mass
transport model


   Gretings!

   I am looking for advice regarding the model I have built in FEFLOW-
   flow and mass transport in transient state, for an unsaturated
   model.

   The model is based on conceptual hydrostratigraphy, field data and
   parameters as taken from referenced literature. However, for some
   reason, I have the feeling that I get too much dispersion through the
   model domain.

   If anybody could give me some advice regarding this issue, I can
   provide more detailed information.

   Many thanks,

   Monica

Gretings!

I am looking for advice regarding the model I have built in FEFLOW-
flow and mass transport in transient state, for an unsaturated
model.

The  model is based on conceptual hydrostratigraphy, field data and
parameters as taken from referenced literature. However, for some
reason, I have the feeling that I get too much dispersion through the
model domain.

If anybody could give me some advice regarding this issue, I can
provide more detailed information.

Many thanks,

Monica

On behalf of John Doherty, Jim Rumbaugh, and myself, please consider joining
us at the first-ever PEST conference!

This first-ever PEST Conference will be held in The Stained Glass Hall of
the Bolger Center, Potomac, Maryland ( http://bolgercenter.dolce.com/
<http://bolgercenter.dolce.com/> ) November 2nd through 4th, 2009. The
primary goal of the PEST Conference is to bring together modelers from a
wide variety of disciplines who either have experience in, or would like to
learn more about, the use of inverse modeling techniques - i.e., parameter
estimation and uncertainty analysis - with a particular focus on the PEST
suite of programs (www.sspa.com/pest ). The objective of bringing together
modelers from a variety of modeling disciplines is to exchange ideas,
discuss applications of the PEST suite of programs, share lessons learned,
discuss new and planned developments, and seek guidance from modelers on
inverse modeling needs to guide future code development. It is also hoped
that this forum will provide an opportunity for modelers to meet and discuss
novel approaches that they have taken to solving problems that they have
encountered.

The PEST Conference will commence with a message from John Doherty, the
developer of the PEST programs. John will provide some history of the
development of PEST, discuss wide ranging applications of PEST, outline
planned future developments, and doubtless wax lyrical on a great many other
topics! The conference will follow with morning and afternoon sessions, each
commencing with a key-note address given by a noted environmental modeler,
followed by submitted oral presentations. A poster session will also be held
one evening. Oral and poster presentations will be summarized in extended
abstracts and/or full papers that will be published in electronic
proceedings distributed on thumb drives. The conference will wrap up with a
question-and-answer session during which attendees will be able to ask
questions of the organizers and of John Doherty, in particular, and provide
suggestions for future development directions.

A one-day Introductory PEST course will be held immediately prior to the
conference, and a two-day advanced PEST course will be held immediately
following the PEST Conference, with instruction from John Doherty, Jim
Rumbaugh, and Matt Tonkin.

Further information about the PEST Conference - including the list of
keynote speakers and information on registration, accommodations, and
travel, will be posted soon at www.sspa.com/ThePESTConference.

We hope to see you in November 2009!

Best wishes -

Matt Tonkin
SSP&A
Email:  <mailto:pest@...> pest@...

Dear all,

I'm a new member from italian feflow users group. I'm modeling the effects of an
underground impervious barrier on the groundwater flow. Could you indicate me
publications, papers or any references explaining the feflow useful in such a
case? This could convince the client to use feflow instead of modflow!!!!!

thank you so much

riccardo

Dear Group Member,

With reference to my earlier queries (did not get any response at that time), a
recent response from Mr. Alessandro Casasso is placed below.

Regards
Kumar
==================================================
C. P. KUMAR
Scientist 'E1'
National Institute of Hydrology
Jal Vigyan Bhawan
Roorkee - 247667 (Uttarakhand)
INDIA

Web Page : http://www.angelfire.com/nh/cpkumar/
==================================================

******************************************************************

Re: Modelling of seawater intrusion
Monday, September 22, 2008 3:52 PM
From: "alessandro.casasso" <alessandro.casasso@...>
To: "C. P. Kumar" <cpkumar@...>

Have you found any answer to you questions? I'm working at a MS thesis about
Feflow modelling of a shallow aquifer in Venice. I will not try to model salt
pans - too difficult even to think where they are.

About rainfall and evapotranspiration: I've got rainfall and temperature data. I
calculated ET with Blaney-Criddle formula, but I found that results are
overestimated. I tried to reduce risults by comparing modeling results with real
results (in the area I'm studying, I can get results from 11 piezometers..) and
I found that BC formula results can be divided by 3. I found that ET estimation
is one of the most difficult parts of shallow aquifers modeling...

I've got no idea about brackish water in rivers. In my model, I assigned the
tidal oscillations (1st type boundary conditions) also to a channel of Venice
lagoon that encloses my modeling domain.

I developed a relation between TDS and conductivity (I've got specifical
conductivity measures), but I did a very rude approximation. As I'm modeling a
peninsula, I thought that seawater contains most NaCl , so conductivity
(microSiemens per cm) is dominated by NaCl concentration. Conductivity is linked
to NaCl concentration in this way: - every ion has an equivalent conductivity,
that is the specifical conductivity for a concentration of 1 equivalent/liter
(for NaCl, 1 equivalent = 1 mole); - this equivalent conductivity is also linked
to concentration by Onsager formula; - specifical conductivity = equiv conduct x
concentration [mole/liter]

I visited your site some time ago, I found it very interesting. Sorry for my
English, I have to improve it. About my tip on TDS-conductivity: as we say in
Italy "here I tell it, and here I deny it" :-) I'm only a MS student and I got
these advice reading a laboratory chemistry manual...

See you soon on this forum,
Alessandro Casasso

******************************************************************

Date: Sun, 20 May 2007 20:03:41 -0700 (PDT)
From: "C. P. Kumar" <cpkumar@...>
Subject: Modelling of seawater intrusion
To: hydforum@yahoogroups.com, hydrologymodel@...,
gwmodel@yahoogroups.com, gwrm@..., rhydrology@yahoogroups.com,
feflow@..., seawat@..., coastal@googlegroups.com

Dear Group Member,

I am grateful to the following members/experts for their interesting/useful
observations/comments/suggestions on my report "Modelling of a Coastal Aquifer
using FEFLOW" (available at ftp://ftp.wasy.de/FEFLOW/Goa.pdf ).

(1) Reinhard Zapata (Waterloo Hydrogeologic, Canada)
(2) Krishnaiah C. (India)
(3) S.V.N.Rao (Roorkee, India)
(4) V.V.S. Gurunadha Rao (Hyderabad, India)
(5) Michael Jorgensen (Australia)

I am prompted to seek further suggestions for the following issues in modelling
the seawater intrusion in coastal aquifers.

(a) How to model the effect of salt pans on groundwater in coastal areas?

(b) How to incorporate the evaporation from open water surfaces (e.g. to define
time-variant boundary condition in case of rivers) and evaporation from shallow
groundwater table?

(c) How to model the effect of brackish water in rivers (due to tidal backwater
effect from sea) on groundwater in coastal areas?

(d) How to develop correlation between resistivity values and TDS and between
resistivity values and hydraulic conductivity.

(e) Suitability of Kriging, Akima and Inverse Distance Weighting techniques for
interpolation/regionalization of different parameters/variables.

Any suggestions for the above will be helpful for extension of this (or similar)
study in future.

There is a small errata in the report - title of figure 7 may be read as
"Measured Values of Hydraulic Conductivity (*10E-4 m/s)" - the multiplier was
missing.

Regards
Kumar
==================================================
C. P. KUMAR
Scientist 'E1'
National Institute of Hydrology
Jal Vigyan Bhawan
Roorkee - 247667 (Uttarakhand)
INDIA

Web Page : http://www.angelfire.com/nh/cpkumar/
==================================================

Hallo

you go through DHI website and contact their branch office in Delhi for
purfchasing FEFLOW software.

S.Halder


--- On Fri, 12/9/08, neerajdsharma <neeraj_me_env@...> wrote:

From: neerajdsharma <neeraj_me_env@...>
Subject: [feflow] feflow software
To: feflow@...
Date: Friday, 12 September, 2008, 12:57 AM

hello friends

i am neeraj sharma . i am pursuing ph.d on groundwater quality in
coastal area for that modelling is required. I am not in position to
purchase the FEFLOW software can any one provide free or any way to
get free fullfeatured FEFLOW software.

Hello sir,

   Thanks, I want to one thing, which address i will send that abstract or any
other application form will be there and also please inform last date.

   Thanks a lot......

   Regards
   Murugan Ramasamy


"peter.schaetzl" <p.schaetzl@...> wrote:
           Hello,

DHI-WASY (the manufacturer of FEFLOW) can provide free FEFLOW licenses
for selected PhD students for the time of the PhD study.

Qualicfication includes that
- the topic of the PhD thesis is interesting to DHI-WAY
- the focus of the work is clearly research-oriented
- the research is leading-edge work
- a summary of the thesis may be published by DHI-WASY.

If you fulfill these criteria, please apply for such a license with a
short (about one page) description of your planned work.

Best regards,
Peter Schätzl

Product Manager FEFLOW
DHI-WASY

Hello,

DHI-WASY (the manufacturer of FEFLOW) can provide free FEFLOW licenses
for selected PhD students for the time of the PhD study.

Qualicfication includes that
- the topic of the PhD thesis is interesting to DHI-WAY
- the focus of the work is clearly research-oriented
- the research is leading-edge work
- a summary of the thesis may be published by DHI-WASY.

If you fulfill these criteria, please apply for such a license with a
short (about one page) description of your planned work.

Best regards,
Peter Schätzl

Product Manager FEFLOW
DHI-WASY

hello friends
   i am neeraj sharma . i am pursuing ph.d on groundwater quality in
coastal area for that modelling is required. I am not in position to
purchase the FEFLOW software can any one provide free or any way to
get free fullfeatured FEFLOW software.