Convergence

July 22, 2002, 08:23

hey guys

I am modeling a ventilated space. when I increase the number of cells the mass residual decreases only in an order of one. Is it possible to reduce it further? For a course grid I get a reduction of order 12, when I triple the grid size there is a problem.

Thanks

MK

July 23, 2002, 13:25

Just a little tip. Check that the Y+ of any cells near any solid walls is greater than 11, usually cell sizes should be such that the Y+ is in the range of 30 - 500. I have found in my research that failure to stick to the correct bounds for Y+ can result in lack of convergence and very long solution times.

Good luck

James

July 29, 2002, 05:32

July 22, 2002, 08:23	Convergence	#1
Mohaba Guest Posts: n/a	hey guys I am modeling a ventilated space. when I increase the number of cells the mass residual decreases only in an order of one. Is it possible to reduce it further? For a course grid I get a reduction of order 12, when I triple the grid size there is a problem. Thanks MK

July 23, 2002, 13:25	Re: Convergence	#2
James Date Guest Posts: n/a	Just a little tip. Check that the Y+ of any cells near any solid walls is greater than 11, usually cell sizes should be such that the Y+ is in the range of 30 - 500. I have found in my research that failure to stick to the correct bounds for Y+ can result in lack of convergence and very long solution times. Good luck James

July 29, 2002, 05:32	Re: Convergence	#3
Mohaba Guest Posts: n/a

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