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problem in size of elements in unstrucutured grid.

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Old   April 23, 2015, 23:02
Default problem in size of elements in unstrucutured grid.
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Ankur Bhatnagar
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hey,

I am creating an unstructured mesh over a body that is having kind of pencil shape with blunt leading edge(image given below).All over the body grid is good but at the leading edge size of elements is very big that is causing problem for my solver(su2).can u please help me how should i reduce size of these elements at the leading edge?
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Old   April 24, 2015, 10:04
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Travis Carrigan
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Hello Ankur,

Select your block and go to Grid, Solve and then the Attributes tab. Expand the Algorithm section and change the number of iterations to 2 and reinitialize the block.

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Old   April 24, 2015, 10:33
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Ankur Bhatnagar
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hello sir,
can u just elaborate about the problem i am struggling with ?
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Old   April 24, 2015, 10:37
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Occasionally the isotropic tet mesher will create pockets of large elements given a wide range of very small and very large boundary spacings coupled with a small convex object in a large farfield. Typically this can be alleviated by increasing the number of isotropic solver iterations performed when generating the block. Another method is to identify the region as you've done in the image above and introduce a baffle to locally control the cell size. This doesn't happen that often, but when it does those are the techniques we recommend.
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Old   April 24, 2015, 10:48
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Ankur Bhatnagar
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tnxx for your reply sir..

how can i locally decrease the size of elements apart from using multiple iteration? any other option that locally reduce size?
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Old   April 24, 2015, 11:04
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Yes, using a baffle will decrease the local size. Create a domain at that location that has the size you'd like and add it as an internal face to the unstructured block. You can use Chapter 12 of the Tutorial Workbook as a guide.
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Old   April 24, 2015, 11:07
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thanks a lot sir..
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