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Old   April 13, 2012, 22:49
Default Structured or Unstructured???
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I'd appreciate it if someone answers this question:
is fluent a "structured" or "unstructured" solver?
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Old   April 16, 2012, 02:03
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unstructured
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Old   April 16, 2012, 14:19
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What do u mean by structure and unstructured. it is in sense of mesh?
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Old   April 16, 2012, 14:38
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http://www.innovative-cfd.com/cfd-grid.html

unstructured solver can handle both structured and unstructures mesh
structured solver can handle only structires mesh

but i actually only know unstructured solver
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Old   April 16, 2012, 21:22
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Quote:
Originally Posted by James Hetfield View Post
I'd appreciate it if someone answers this question:
is fluent a "structured" or "unstructured" solver?
unstructured

Quote:
Originally Posted by banty View Post
What do u mean by structure and unstructured. it is in sense of mesh?
structure/unstructure can refer to both grids and solvers. He asked specifically for the solver.
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Old   April 16, 2012, 21:27
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thanks everybody
I dont know why there isnt any option to switch to STRUCTURED solver in fluent
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Old   April 16, 2012, 21:47
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thanks everybody
I dont know why there isnt any option to switch to STRUCTURED solver in fluent
Suppose you purchased a retail car that can drive on a well-paved road, do you expect it to run on railroad tracks? Same idea.

Structured solvers are severely limited in the types of problems they can solve, which means commercially it is not very viable. And then throw on top of that the difficulty in obtaining a structured mesh for the same problem.

Recall that unstructured meshes allow significantly better grid quality and reduced grid size (at the expense of some storage memory for the grid). For complex geometries, the savings that you would have otherwise obtained by using a structured mesh + solver are not worth it you end up need a bigger mesh regardless.

Structured meshes are really only viable for very simple geometries. Given the computing power of modern computers (and memory available), not many people bother.
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Old   April 19, 2012, 09:38
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Grid topology can be structured (single block, multiblock) or unstructured. Then the grid information can be saved in a structured way (only structured grids) or an unstructured way (both structured and unstructured).

The way you save the grid information is related to the way your solver is expecting it. Fluent is an unstructured solver, which means it stores and reads the grid information in unstructured format. This does not means you can't use a structured grid in Fluent but simply that it is stored as an unstructured grid so, at the code level, all the grid read by Fluent are unstructured (and the numerical methods used on them are limited by this).

You don't have any switch in Fluent because it only reads grids written in unstructured format (either they were originally structured or not).
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