Can y+ be much smaller than 1 for...

May 18, 2001, 18:43

Before meshing my Spalart Allmaras NACA 0012 airfoil, I calculated the y for y+=1 for the 2 layer model.

After the simulation I plotted y+ and obtained values as low as 0.1 My question is if's alright to keep using this mesh (is there an induced error or something that can go wrong)

I saw the Fluent manual but it does'nt say anithing about y+<<1

May 18, 2001, 19:42

(1). Well, if your mesh size is fixed, then shifting the mesh distribution to the wall will make the mesh coarser in other part of the boundary layer,right?

June 7, 2001, 23:32

Does y+ adaption shift the mesh or just refine the mesh near the boundary?

June 7, 2001, 23:38

I think y+ can be smaller than one... see Kays and Crawford, Convective Heat and Mass Transfer page 201 to 202. y+ = yu(tao)/mu... Let me know what you find.

May 18, 2001, 18:43	Can y+ be much smaller than 1 for...	#1
Rodrigo Madariaga Guest Posts: n/a	Before meshing my Spalart Allmaras NACA 0012 airfoil, I calculated the y for y+=1 for the 2 layer model. After the simulation I plotted y+ and obtained values as low as 0.1 My question is if's alright to keep using this mesh (is there an induced error or something that can go wrong) I saw the Fluent manual but it does'nt say anithing about y+<<1

May 18, 2001, 19:42	Re: Can y+ be much smaller than 1 for...	#2
John C. Chien Guest Posts: n/a	(1). Well, if your mesh size is fixed, then shifting the mesh distribution to the wall will make the mesh coarser in other part of the boundary layer,right?

June 7, 2001, 23:32	Re: Can y+ be much smaller than 1 for...	#3
Chetan Kadakia Guest Posts: n/a	Does y+ adaption shift the mesh or just refine the mesh near the boundary?

June 7, 2001, 23:38	Re: Can y+ be much smaller than 1 for...	#4
Chetan Kadakia Guest Posts: n/a	I think y+ can be smaller than one... see Kays and Crawford, Convective Heat and Mass Transfer page 201 to 202. y+ = yu(tao)/mu... Let me know what you find.

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