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Longitudinal dispersion coefficient

Sat, 11/21/2009 - 5:02am — jparsa
Dear collegues The model uses constant dispersion coefficient along a water body. I think it should be given as a function of x. What the model does not consider the variable longitudinal dispersion coefficient? Is there any plan to modify the model to consider the variable longitudinal dispersion coefficient? Regards J. Parsa
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Water Quality
Mon, 11/23/2009 - 12:42pm — chris

We've used varying longitudinal dispersion coefficients in the past for specific applications but it required hard wiring the code. I'll pass along your suggestion to Scott Wells. regards, chris
Wed, 11/25/2009 - 2:19am — jparsa

Dear Chris In which cases (i.e., reservoir, lake, estuary) you used the varying dispersion cofficients? Did it affect on the results more? What difficulties you had in coding? I would like to modify the code in order to consider the varying Dx. I have the Compaque Visual Fortran 6.5. How can I run the code(i.e., the sequence of running files)? regards Javad ============================================== Javad Parsa PhD Candidate College of Civil Engineering Iran University of Science and Technology Tehran, Iran ==============================================
Wed, 11/25/2009 - 12:51pm — chris

Hi Javad, We used variable longitidinal dispersion on a river that we had dye study data available. The variable in the code is called 'DX', and it is a function of layer number (subscript k) and segment number (subscript i), although it is set to the value (constant for each water body) you specified in the control file. The coding shouldn't be too difficult. You'll need an input file that has your specified values of DX, and you'll need to add the code setting DX to values from this input file. chris