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Nnoxis August 6, 2021 16:56

0D and 1D numerical modeling
 
Hello everyone.

I am looking for definitions or specific informations on 0D and 1D numerical modeling and examples of applications.

Also a comparison with 3D CFD numerical modeling.

And thank you very much for your support.

piu58 August 7, 2021 03:13

I don't think that is a thing like 0D fluid dynamics. Fluid means flow, and flow needs a direction.

0D simulation may be calculations of chemical equilibrium or so.

There may be applications for 1D fluid dynamics. That means that the flow has changes only in one direction. Such simple cases often don't need a numerical simulation and can be examined with pure mathematics. Often, you have some kind of coordinate transformation here, e.g. form spherical coordinates to 1D.

sbaffini August 7, 2021 04:49

As the terms imply, they refer to problem formalizations that lack several or all of their spatial extensions. These can be used when the problem indeed has very small variations in the neglected dimensions, but also when more dimensions are not computationally affordable and the missing dimensions are accounted for by some model/trick.

A 0D description lacks any spatial extension, thus it either is an algebraic equilibrium relation or an unsteady evolution equation (a time dependent ODE). Chemical reactions (or their fast chemistry approximation) are, as mentioned, a good example. But you also see them in system level codes, where maybe a whole pump is modeled in this way.

A 1D model instead only retains one significant spatial dimension in some problem description. Imagine flows in long pipes, or human blood flow. But, again, system level codes will necessarily use such 1D descriptions even when not applicable (e.g., a short pipe between two large 0D sub-systems).

Nnoxis August 7, 2021 16:03

Thank you all for your support.


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