Which of these is correct for extra viscous terms in cylindrical coordinates?
(a) The implicit and explicit treatments do not depend on the sign of the coefficients
(b) It is treated implicitly when its contribution to the coefficient of the central node is negative
(c) It is treated implicitly when its contribution to the coefficient of the central node is positive
(d) It is treated explicitly when its contribution to the coefficient of the central node is positive
I got this question by my school principal while I was bunking the class.
The question is from Incompressible Flows topic in division Incompressible Flows & Compressible Flows of Computational Fluid Dynamics