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Transport of diluted species - Problems with MASS CONSERVATION
Posted 20.07.2016, 03:49 GMT-4 0 Replies
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I have a question with one model that I am building. I am modeling the concentration with respect to time in a close chamber with initial concentration C0 using the Physics "Transport of diluted species". I only have one velocity in the y direction which is a function of y. Vy = (H/2 - y) * S, where H is the height of the chamber (in meter) and S is the flow rate (in 1/s). From the equation, I expect at steady state, the concentration of the species will be highest at the midline of the chamber. However, the TOTAL concentration of the species in the chamber should still be the same since it is a CLOSE CHAMBER (no inflow, no outflow). However, the total concentration is not conserved (since the volume and the total AMOUNT in a close chamber do not change, thus, total concentration should be the same). This does not follow conservation of mass law.
I wonder if there is a recommended physics or tips to deal with the non-linear system since I have the velocity in the y-direction is a function of y. Please see the attached file see how the system is set up.
My parameters are: H = 250 [um] and C0 = 4.98E-6 (mol/m^3)
Thanks,
Uyen
Hello Uyen Tran
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