Search the Community
Showing results for tags 'rt3d'.
Found 3 results
alexxander posted a topic in Using GMSHello !!!!! I am making a simulation of a tracer test with three injection wells (north) and one pumping well (south). On the injection wells we have injected the salt and water for 16 hours and then successively water for two months. After 16 hours of injection (the initial concentration was 330g/l), we started to pump almost the same amount of water injected on the north on the same time span. we have found the Kx values that match the arrival times of the breakthrough curve at the observation points, according to the pathlines. The problem is that I am getting Nacl concentrations that are too high compared with the values I have measured (calculated from the electric conductivity at the observation point converted in Nacl concentration). The aquifer thickness is about 30 meters. My question is, according to the above mentioned; is there any way to reduce the concentration at the observation well (40 meters downgradient of the injection well). There should be no adsorption or other phenomena within the aquifer, or at least we expect that. The concentrations should be around 10mg/l, however, the concentrations I am getting are around 1800mg/L * could it be possible to use double density approach to solve that problem? * RT3D gave me better results than MT3D, setting in both cases NO reaction (tracer transport), but setting in the CHEMICAL REACTION PACKAGE A value for the Linear isotherm a first sorption value of 1e-3, could that value influence a lot? Thanks a lot for your reply and possible suggestions Alexxander
Dylan8 posted a topic in MODFLOWHi everyone, I am currently doing a project regarding in-situ chemical oxidation of BTEX using persulfate solution, and trying to use RT3D to represent the process. As reading the literature the reaction should be a pseudo 1st-order kinetic reaction model, but the only relevant option I found in the reaction package is the inst. aerobic degradation of BTEX which only offers oxygen as the electron acceptor. In this case, could someone familiar with the persulfate or other similar oxidation mechanisms tell how to construct the RT3D model? convert the persulfate concentration to an equivalent oxygen concentration? or should I try more options other than MODFLOW? Regards Dylan
Just came up with a question regarding where to apply different solution schemes for the advection package activated in the MT3D or RT3D model, and the cases are based on the tutorials 1. Can someone please explain further why we choose the Standard finite difference method for both the Sequential anaerobic degradation and BTEX degradation with multiple electron acceptors, MMOC for the Rate-limited sorption reaction, MOC for both Instantaneous aerobic degradation and Double-Monod model, 3rd order TVD (ULTIMATE) for all MT3D tutorial cases, etc. If there were relevant recommended reading resources, that would be greater. 2. In the Rate-limited sorption reaction tute, what is the meaning of changing Max. number of cells any particle will be allowed to move per transport step to 2 in the Particle dialog of the Advection package? 3. How to save multiple solutions as a .rts file like what it supposed to import in the Rate-limited sorption reaction tute. Because each time I ran the model it would overwrite the existing solution with a new solution of both Aqueous and Soil given a certain mass transfer coefficient. How to come up with a solution with different runs (i.e. different mass transfer coef in one solution file? Thanks, Dylan