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About cansudemir

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  1. Hello, For a very long time, I have been trying to create a numerical model of an aquifer with complex hydrogeology (by using borehole-to-Ugrid option). I had several layers of 4 different materials. But all my efforts were trash. Because, I have never obtain a successful Modflow-usg run. They never converged. Although wetting option was on, the aquifer had so many dry cells. And these dry cells were always at same locations (not near/at the location of wells). It was meaningless. I couldn't run the PEST. So I decided to make my system more basic and created a one-layer model with HK zones. It worked well without the wetting. I have applied pilot points approach for the calibration. And pest is working because the forward run has a successful result. However, this time the calculated residual is too high. I have done many things to decrease the error. But the best result until now is about 7000 (Sum of Squared Weighted Residual Head+Flow) and for Root mean squared residual it is 16. These values are so big. Interestingly, the computed vs. observed head plot (attached) looks not so bad that there should be a way to fit them to the line. I only have head observations in my hand and I don't have any flow observations data. May this be the problem? Or what may be the problem? Could you please help me on this? I would be so happy to hear your recommendations to lower my calibration error to an acceptable value. Note: The computed heads are higher than the measured heads. The boundary conditions are ; specified head along the coast and GHB condition was assigned to some part of the boundary. The model is steady-state. Thank you! Best, Cansu
  2. LPF package

    Dear @Alan Lemon, Regarding your above reply; In my case similar to above, when I assign negative values for HK zones, the run results completely wrong. With the negative values I do can create key parameters by using "initialize from model". But the model doesn't run properly. On the other hand, with positive HK values I got a successfully finished run. However in this case, I couldn't initialize the key parameters from the model and don't know how to create parameters by hand. What should I do? Should I just add new parameters? If so, how does the program understands that these parameters indicate my assigned HKs? Best, Cansu
  3. Tracking particles in Modflow-USG doesn't works

    Hello Dear @Alan Lemon, Has the bug regarding the contour labeling for UGrid been solved? I am still using GMS 10.1.3. and have a strange kind of fear that if I download the updated versions, I won't be able to open the older versions on which my whole study depends. But this contour labeling is a serious problem for my studies right now so if this error was solved in one of the following versions of GMS I will download that. I need your help. Thank you. Best, Cansu
  4. Hi there, I'm having a problem related with assigning specified flow boundary conditions to my UGrid / Modflow-USG model. The error appears when I do the '' Map to MODFLOW'' option while converting my conceptual model to UGrid numerical model. I have read the helping document saying that If you want to use ''Specified flow boundary condition'' the UGrid must be a stacked grid. A stacked grid is one in which there is no vertical discritization of layers and the horizontal discritization of all layers is the same. (i.e. the Index of Vertical Sub-Discretization (IVSD) in the UnStructured Grid Discretization (DISU) package could be set to -1) (See the Figure attached). Firstly, I did not understand what this means and how to find the IVSD in the DISU package and set it to -1 to be able to use specified flow boundary condition. In my model there are 2 groundwater divide boundaries which must be zero flow and 2 formation boundaries where the aquifer feeds from neighboring formations with a specified flow value. If I ll have to change my specified flow bound. cond. with something else or If there is a way to use them, could you please help me to find the solution? Thank You!