Source Term in k-equation of k-epsilon turbulence
 

Hi,

The source term given in k equation of the k-epsilon turbulence model is given as

tau(t,ij)Sij in tensor form where tau(t,ij) is turbulent Reynolds Stress and Sij is the strain rate.

Can anyone guide me on how it will expand. In my view it can be :

tau(t,xx)*S(xx) + tau(t,xy)*S(xy) + tau(t,xz)*S(xz) + tau(t,yx)*S(yx) + tau(t,yy)*S(yy) + tau(t,yz)*S(yz) + tau(t,zx)*S(zx) + tau(t,zy)*S(zy) + tau(t,zz)*S(zz)

I want to know whether the expansion is correct or not; if not how the source term should be calculated.

Thanks

Apurva

Re: Source Term in k-equation of k-epsilon turbule
 

The definition of generation term in k is G=TAUij*(dUj/dXi)

Your expansion is right. If normal Boussinesq hypothesis is used, then

G=Mu_t*(S*S)

where S=SQRT(2*Sij*Sij)

and Sij=0.5*(dUi/dXj+dUj/dXi)