Question

The second step of the ADI scheme is swept over __________ direction.

(a) both the x and y

(b) the x

(c) the y

(d) the time

This question was posed to me during an interview for a job.

My doubt is from CFD Techniques in division Some Simple CFD Techniques of Computational Fluid Dynamics

Answer 1

The correct choice is (c) the y

The best I can explain: The second step of the ADI scheme uses the time domain from t+\(\frac{\Delta t}{2}\)  to t+Δt. Here, the y-derivative is treated implicitly after replacing the derivatives with central differences. The solutions are swept in the y-direction here.