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-   -   Dynamic_Mesh for large mvt : remeshing parameters! (http://www.cfd-online.com/Forums/fluent/31338-dynamic_mesh-large-mvt-remeshing-parameters.html)

caloggero April 22, 2003 09:16

Dynamic_Mesh for large mvt : remeshing parameters!
 
Hi, everybody! I'm dealing with dynamic mesh to model the movement of a rotating 2D-airfoil around a fixed point at a distance (radius) of 1.2 m (at the grid scale, for a chord length of 1m).initial mesh is a triangular one, and I'm using the spring smoothing and remeshing options.the problem is that when the foil rotates, the remeshing is of a very bad quality!! with a time step of 1e-03 it doesn't create errors but I'm not sure I'll get any result from that kind of meshing! if someone has met similar case, please give me indication of the remeshing method and values. thanx

cip May 5, 2003 15:02

Re: Dynamic_Mesh for large mvt : remeshing paramet
 
make the maximal volume smaller and change also the skewness in 0.6

calogero May 6, 2003 05:35

Re: Dynamic_Mesh for large mvt : remeshing paramet
 
Hi CIP! thanx for your response! I tried previewing the dynamic mesh with max_cell_vole qual to the original grid one ie:0.05226312, and the Max_cell_skewness=0.6. the mesh has improved quality in the viscinity of the foil, but is still bad elsewhere! I noticed also that it prints in the mesh statistics (when running) a value of max_cell_vol less than the one I specified !!! without crashing! the dynamic mesh parameters am using are:

************************************************** ****************

SMOOTHING: spring constant factor=0 Boundary node relaxation=1 (default) convergence tolerance=0.001 (default) number of iterations=20 (default) REMESHING: +must improve skewness Min_cell_vol= original grid's one Max_cell_vol= original grid's one Max_cell_skewness=0.6 size remesh interval=10 (default) ************************************************** ****************

have you already dealt with such a case before? with large movement?

ciprian May 6, 2003 05:44

Re: Dynamic_Mesh for large mvt : remeshing paramet
 
fluent always has problems like this. the results are not afected if youre having a suficient small cells in the proximity of the foil. if you really want to have a better mesh go in gambit and make the new mesh using tools /function size and make a new test. cip


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