Question

Which of these methods is used to treat the non-orthogonal diffusion term?

(a) Deferred correction

(b) Predictor–corrector

(c) Green-gauss

(d) Trial and error method

I have been asked this question during a job interview.

This is a very interesting question from Diffusion Problem in chapter Diffusion Problem of Computational Fluid Dynamics

Answer 1

Correct choice is (a) Deferred correction

To explain: The cross-diffusion term cannot be expressed in terms of nodal values. So, deferred correction is used here. Its value is computed using the current gradient field and this is added as a source term in the right-hand side of the algebraic equation.