Anita Zeng

Dear Jia ~ Thanks again for your assistance and teaching. The example is from a textbook about mass transport of solutes. You can see the attached file for the original question. Cl- 30mg/L is the value of analytical solution calculated by the formula. I want to get the value of numerical solution by GWB, then confirm the difference between these two method. If I model a continuously leaking point source contamination for 1 year, the wave crest of solute don’t move in the resulting graph (X-position vs. Cl- in fluid (mg/l)) with time and distance. So I think it’s not continuously leaking for 1 year. The time for contaminant leaking should be very short, so we can see the moving of solute slug with time and distance (like figure 11.11 in attached file). Thank you. example.pdf

Dear Jia ~ Thanks for your response. In this problem, Cl pollutant is instantaneous leaking to groundwater layer, then compute the Ccl- at d=15m after 1y from the leaking point. Therefore, I set two different fluids in Fluids pane and two reaction interval in Intervals pane. If I set one minute(or one second) reaction interval for the contaminated fluid to enter the system at the inlet and the remaining time flushing the system with dilute fluid, the program cat't run. It shows "residuals too large, 669-th interation, Newton failed at node 0, ............ , Abandoning simulation". What's wrong with this. How can I correct the setting so that the program can run normally? Thank you. 1D nonreact-6instant.x1t

hi~ I'm just beginning to learn GWB. I am confused about the boundary condition setting of a single point source pollution for one-dimensional mass transport. Attached are the questions and the setting of X1t simulation parameters. Maybe I guess there are something wrong on the Intervals pane, so it can't be runing. But I don't know how to modify the setting. Could you please help me, thank you. Question of non-reactive one-dimensional solute transport.pptx 1D nonreact-2.x1t