Reply To: ComputeNusselt
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May 20, 2021 at 9:41 am
#5683
stephan
Moderator
Dear Mike,
thank you for your post.
Please note that “rho” on the ADlattice refers to the zeroth moment in LBM terms, which is now the temperature (in contrast to density on NSlattice).
In the example code the computeNusselt function does:
/// Compute the nusselt number at the left wall
Hence the function uses an approximation to the normalized temperature gradient (q := local Nu = normTempGrad * L) with a finite difference (second order forward) at boundary nodes:
q += (3.0*T_x – 4.0*T_xplus1 + 1.0*T_xplus2)/2.0*N;
BR
Stephan