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Lagrangian multiplier and the flux

Posted 27 mai 2015, 18:11 UTC−4 Chemical Reaction Engineering Version 5.1 0 Replies

Robert Zhang
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Hello everyone,

I want to ask a bunch of conceptual questions here about Lagrangian multiplier:

For the Transport of dilute species module, in order to resolve a diffusion problem with flux, we need to introduce the weak form at the boundary in order to allow the flux to flow into or out of the surface. Now just by looking the unit of the Lagrangian, why it is m for the 2D case and m^2 for the 3D case, at the boundary constraint when you use the weak form? What is the relationship between the Lagrangian integration at the boundary and also the embedded variable chds.tflux_variable integration (because these two integrations do not equal with each other)? If the flux is large enough, can we solve the problem by not using the Lagrangian multiplier (weak constraint) at all?

Any idea or suggestion will be greatly appreciated.

Thanks!!
0 Replies Last Post 27 mai 2015, 18:11 UTC−4
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