What is the disadvantage of over-relaxation?(a) Stability is decreased(b) Divergence is increased(c) Oscillations are increased(d) Convergence is increasedThis question was addressed to me at a job interview.My doubt is from Under-Relaxation topic in portion Discretization of the Source Term & Relaxation of Computational Fluid Dynamics

What is the disadvantage of over-relaxation?(a) Stability is decreased

1.	What is the disadvantage of over-relaxation?(a) Stability is decreased(b) Divergence is increased(c) Oscillations are increased(d) Convergence is increasedThis question was addressed to me at a job interview.My doubt is from Under-Relaxation topic in portion Discretization of the Source Term & Relaxation of Computational Fluid Dynamics
Answer» Right answer is (a) STABILITY is DECREASED The EXPLANATION: When the relaxation factor is more than one, the PROCESS is called over-relaxation. This will lead to a higher rate of convergence and leads to faster convergence. But, the disadvantage is that stability will be decreased.

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