Question

In a control volume adjacent to the boundary, the flux crossing the boundary is _______________ in the discretized equation.

(a) set to some arbitrary constant

(b) set to zero

(c) introduced as a source term

(d) introduced as a convective flux

This question was posed to me in examination.

This interesting question is from FVM for Multi-dimensional Steady State Diffusion in chapter Diffusion Problem of Computational Fluid Dynamics

Answer 1

The correct answer is:

(c) introduced as a source term

Explanation:

In the context of the Finite Volume Method (FVM) for multi-dimensional steady-state diffusion problems, when dealing with the boundary of a control volume, the flux crossing the boundary is typically introduced as a source term in the discretized equations. This is because boundary conditions often impose specific values or behaviors on the flux at the boundary (such as no flux or a specified flux), and these conditions are incorporated into the equation as source terms to ensure the correct behavior at the boundary.