question in cfdAssembleStressTerm.m about boundary condition

[liuqi45]

for ZeroGradient boundary condition in cfdAssembleStressTermInletZeroGradientBC and cfdAssembleStressTermOutletZeroGradientBC,
the code is

'local_FluxCb = mu_b.*geoDiff_b;'
'theFluxes.FluxCf(iBFaces) = local_FluxCb;'

but according to the book FVM in CFD, the theFluxes.FluxCf(iBFaces) should be 0. I feel puzzle here

[shanjierenyidp]

Hi liuqi, I think in the cfdAssembleStressTermInletZeroGradientBC code, the author only implemented the two types of wall BC and one symmetry BC following the book. However, the inlet and outlet BC are just duplicating the interior method. According to the book, cfdAssembleStressTermOutletZeroGradientBC should have the form of (15.139), where FluxCb should be mdotfb, fluxFc should be zero, and fluxVb should add contribution from pressure