How to form a constant profile in the empty domain

August 22, 2006, 16:36

Hello,

That is an old question, but nobody answered it(or I can't get the answer).

According to the reference on neutral atmospheric boundary layer, the inlet boundary is defined as velosity U(z)=u*ln(z/z0)/k, K=u*^2/SQRT(Cu),Epsilon(z)=u*^3/k*z, outlet is set as outflow.sides and top as symmetry. the data was got from the previous wind tunnel test.

Realisable k-eps,two layer wall funciton,smooth wall, structured mesh and second order were used in the empty domain. After convergence, there was a large difference between inlet profile and outlet profile. Then grid was refined, but the problem still existed.

What is the reason of it? How can I achieve the consant profile in the empty domain?

Thanks

Justin

August 23, 2006, 08:43

Do I need to use cyclic condition between inlet and oulet?

August 22, 2006, 16:36	How to form a constant profile in the empty domain	#1
justin Guest Posts: n/a	Hello, That is an old question, but nobody answered it(or I can't get the answer). According to the reference on neutral atmospheric boundary layer, the inlet boundary is defined as velosity U(z)=uln(z/z0)/k, K=u^2/SQRT(Cu),Epsilon(z)=u^3/kz, outlet is set as outflow.sides and top as symmetry. the data was got from the previous wind tunnel test. Realisable k-eps,two layer wall funciton,smooth wall, structured mesh and second order were used in the empty domain. After convergence, there was a large difference between inlet profile and outlet profile. Then grid was refined, but the problem still existed. What is the reason of it? How can I achieve the consant profile in the empty domain? Thanks Justin

August 23, 2006, 08:43	Re: How to form a constant profile in the empty do	#2
justin Guest Posts: n/a	Do I need to use cyclic condition between inlet and oulet?

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