# kw sst equation with nonlinear source term

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 February 11, 2018, 06:29 kw sst equation with nonlinear source term #1 New Member   Jenna Yu Join Date: Sep 2014 Posts: 6 Rep Power: 10 Hi, guys！ I am working at kw sst model with my own code. However, the kw equation diverged for 2D plate flow with Re of 1e6. Here is my eg: 1 2d plate flow, Re 1e6, 1st cell height 1e-5, yplus<1, no wall function, inlet velocity is 1m/s, material is water; 2 bottom line is wall boudary; left line and upper line are inlet; right line is outlet; 3 inlet k is 1.5*power((I*U),2), where I is turbulent intensity; inlet w is w=power(Cemu,-1/4)*sqrt(k)/l, where l is turbulent length scale; 4 wall boundary: k is 0; w is related to near wall distance, according to 5 peuso-time method; 6 non-linear source term: same as CFL3D, implicit method; My Questions: 1 boundary condition for kw sst model? eg: inlet, outlet, wall, far-field 2 Initial value for kw, and would bad initial value lead to the divergence of kw equation? 3 How to take care of the nonlinear source term in kw equation? 4 The dt of kw equation and the dt of average fluid flow? Is anyone experienced in solve kw equation? Thank you very much.

 February 18, 2018, 17:32 #2 Senior Member   Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,665 Rep Power: 25 You posted in the "Freelancer" forum. That means you want to pay someone for the help. Is this right?

February 21, 2018, 02:32
#3
New Member

Jenna Yu
Join Date: Sep 2014
Posts: 6
Rep Power: 10
Quote:
 Originally Posted by Gert-Jan You posted in the "Freelancer" forum. That means you want to pay someone for the help. Is this right?
I do not know "Freelancer" forum means that I want to pay someone for the help. I want to seek for help for free, however, if someone, who could help me with this problem, asks for payment we could negotiate the price.

 Tags boundary condition, kw sst, numerical method, stiff source term, wall