Lamm

Dear Users,
I used FEFLOW 5.4 classis, but now I am using FEFLOW 6.1. Because of the new version, so the ways to input data are strongly different. My questions for FEFLOW 6.1 are:

1. How can I input groundwater recharge into the first layer with various polygon and corresponding variable time values?

2. How can I input hydraulic conductivity value for different polygon within one layer?

3. How can I interpolate water level (3rd Boundary condition) in a river?

4. How can I input abstraction wells with variable time values?

I am looking to hearing from you. Please show me step by step of each question.
Thanks so much for your time and help,
Lam

Thanks Peter,

In the option “Temporal & control data” in FEFLOW shows only  “initial time step length” and “ final time step”. You mean the initial time step length = Start time of FEFLOW simulation and final time step = end time of simulation? Is that correct? If not please show me another option to input the time of simulation.

For example: I try to simulate GW for the period of 365 days from 1.1.2010 -31.12.2010. According to your advice, 1.1.2010 and 32.12.2010 will be converted to be 40179 and 40534 by Excel, respectively. Then I will use these converted values of 40179 and 40534 to add starting time and ending time of FEFLOW. Is that correct?

Dear User,

I am using FEFLOW 5.4  to simulate GW flow. The initial time step length (d) is set 0.001 and the final time is 730 day. However the observed data are only monitored in 4 times per every month with specific day. My question related to the comparison of Simulated VS Observed values is:
How can I determine the exact day of simulated results corresponding to the days of observed values? This is because FEFLOW did not show the simulation time (DAY/MONTH/YEAR) when running simulation.

Thanks for your shearing,
Lamm

Thanks Blair so much,
I have a plan to simulate salt intrusion. I suppose that salt could be considered to be on kind of solute (dissolve). Thus, perhaps I must create thin buffer layer within aquitard layers according to your advice.

Hi Users,
My model contains 4 aquifers and 3 aquitards. Vertical order of these layers can be illustrated as Aquifer 1(Aq)-Aquitard 1(At)-Aq2-At2-Aq3-At3-Aq4. Aquitards are assumed to be represented in the model by a single layer between two aquifers. The thickness of these aquitards ranges from 3-20m. I am wondering that these aquitarts need to be created a buffer layer? Is it mandatory to create buffer layer and among these aquitard layers which aquitard layer shoul be created buffer layers?

I am looking forwards to receiving your ideas. Thanks in advance,
Lamm

Hi Blair,
Thanks you so much.
Q1: I understood that you suggested using 1st BC with constant or time varying values for Coastline. For 2D (Vertical), the head can be set for BC at sea level (h=0) at the top of the model and then be corrected with the depth because of the overlaying denser salt water. In term of 2D (horizontal) and 3D, I suppose that the way to set BC may be different from that of 2D (vertical). Basing on Tidal level, I will create time varying data and input them to every note along the Coastline BC. Do you thing is that possible?

Q2. The mountain is located inside Domain, so I can not limit the Domain of model.  Do you think that I could delete every notes both  inside and boundary of the mountain? By doing this How are the influences on  model results?

Lam

Hi Users,

Q1: I want to build a 2D (horizontal) and 3D model. One boundary of my model connects with Coastline. The purpose of my research is to assess the changes between the variations of Sea Water Level (Tidal) on ground water level and salt intrusion. Therefore, I suppose that I may have to set up 1st or 3rd type BC for the boundary connecting with the Coastline by using Time varying water level (Series of Tidal level). Is that correct if I use 3rd BC for Coastline boundary condition? How is the type of input data (constant value or Time varying water level values)?
Q2: There is a mountain in the area of my model, but I want to exclude simulating groundwater in that mountainous area. This is because I don’t know precisely stratigraphic information beneath the mountain (lithological components may consist of sedimentary rock or laterite). How can I do so that the Model does not simulate GW flow in the area of mountain?

Thanks for your time,
Lamm

Hi Peter,
Thanks you very much for your explanation. Could you help me an additional question as follows:

I set up 2D (horizontal) and 3D model. One boundary of my model connects with the Sea. The purpose of my research is to assess the influences of the variation of Sea Water Level (Tidal) on ground water level. Therefore, I suppose that I have to set up 1st type BC for the boundary connecting with the Coastal line by using Time varying water level (Series of Tidal level). Could you please give me your ideas and show me how can I do?

Thank you so much,
Lamm

Hi Users,

In the stratigraphic information of my research area consists of both continuous and uncontinuous aquifers. My questions are:

1) FEFLOW can simulate uncontinuous layers which contains different aquifers?
2) If not, How can I set up uncontinous aquifers in the model?

Thanks in advance,

Lamm

Dear Christian,
Thanks for your explanation
Lamm