Question

When the residuals are scaled, the vanishing value is ___________

(a) less than 10

(b) less than 10

(c) more than 10^-5

(d) less than 10^-5

The question was posed to me in an online interview.

This is a very interesting question from Relaxation in division Discretization of the Source Term & Relaxation of Computational Fluid Dynamics

Answer 1

Correct answer is (d) less than 10^-5

For explanation I would say: The common range of the vanishing value is from 10^-3 to 10^-5 for the scaled residuals. I can also range below this level. The integrated quantities are also used to ensure the convergence of the solution.