turbulence boundary similarity problem
 

hello, everybody

one backward-facing step flow problem

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The height of the flow channel after the step H=20cm,mean velocity u=1cm/s,and Re=2000. the control equations were nondimensionless,so u=1,H=1,in order to satisfy Reynolds similarity,the dymamics viscosity v=5.0x10^(-4),when I use wall function method, how could I cope with the similarity relationship in the region of boundary? Thank you.