Hi all, i got one big doubt,i got DNS of 3D diffussion flame, to check whether my grid ressoulution is sufficient enough or not.. i want to do simple technique like calculating of total production equal to dissipation, am i right , if not please let me know why it is not right? if all scales is ressolved in my DNS, then total production will be equal to total dissipation other wise not.. please respond ur views on this , i am very much eagerly interested to know more about this..

What do you mean? The local production-dissipation of the global (for the whole domain)? There is no balance production- dissipation for the whole domain if you simulate a jet. Look at the transport equation for the mean kinetic energy: advection of K out of the domain = prod - diss integrated over your domain on average. In other words, not all kin. energy is dissipated in the domain because a part is advected out the domain.

/Tom

Hi Tom,

I am talking about global average production equal to dissipation.i want to calculatig of total production -dissipation, based on the transport equation of mixture fraction variance(being my DNS is non-premixed combustion).. please let me know

Hi Tom , For entire domain i want to calculate total production(2*rho*u_i''*z''*dho_z/dho_x)(production term in mixture fraction variance transport equation) equal to total dissipation(2*rho*D*(dho_z''/dho_x)**2).

all these terms are in average scence (in RANS context). i would like to know whether both the terms are equal or not? thankyou in advance