S-A model: nut?

December 20, 2004, 17:24

Hi,

Does anyone know the definition of the "nut"?

When you choose Spalart-Allmaras turbulence model, one of the residual is "nut".

Currently, I guess "nut" is the nu_t, i.e. turbulent kinetic viscosity, but I can't explain why at first iteration its value is alway very small instead of unit 1.

I hope someone could help me.

Many thanks.

Maxmum · May 9, 2010, 12:40

i also want to this point. the calculation can go when I use k-epsilon model, but when it cann't go further when i use SA or DES with SA as ' Divergence detected in AMG solver: nut'

shalia · October 5, 2010, 08:51

Could you find a solution for your problem? cause I have the same P.2

Maxmum · October 17, 2010, 04:51

this problem alwasys caused by your grid.

azna · March 10, 2016, 16:38

Hi,

I was wondering if you find a solution for this problem? I have the same problem as well.

Meer_2 · March 26, 2021, 17:47

Spalart-Allmaras model, boundary and initial conditions).

December 20, 2004, 17:24	S-A model: nut?	#1
Johnix Guest Posts: n/a	Hi, Does anyone know the definition of the "nut"? When you choose Spalart-Allmaras turbulence model, one of the residual is "nut". Currently, I guess "nut" is the nu_t, i.e. turbulent kinetic viscosity, but I can't explain why at first iteration its value is alway very small instead of unit 1. I hope someone could help me. Many thanks.

May 9, 2010, 12:40		#2
Maxmum New Member Maxmum Join Date: Feb 2010 Location: UK Posts: 11 Rep Power: 16	i also want to this point. the calculation can go when I use k-epsilon model, but when it cann't go further when i use SA or DES with SA as ' Divergence detected in AMG solver: nut' Mkun likes this.

October 5, 2010, 08:51		#3
shalia New Member Shobeir Join Date: Oct 2010 Posts: 3 Rep Power: 15	Could you find a solution for your problem? cause I have the same P.2 Mkun likes this.

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October 17, 2010, 04:51		#4
Maxmum New Member Maxmum Join Date: Feb 2010 Location: UK Posts: 11 Rep Power: 16	this problem alwasys caused by your grid.

March 10, 2016, 16:38		#5
azna Member azna Join Date: Nov 2012 Posts: 30 Rep Power: 13	Hi, I was wondering if you find a solution for this problem? I have the same problem as well.

March 26, 2021, 17:47		#6
Meer_2 New Member Meer_2 Join Date: Mar 2021 Posts: 1 Rep Power: 0	Spalart-Allmaras model, boundary and initial conditions).