Question

For fluid flows, which expression does not characterize the slow flow of a viscous and incompressible fluid in a closed domain?

(a) v.∇v=0

(b) μ≠0

(c) =0

(d) =0

The question was asked in final exam.

Query is from Governing Equations topic in chapter Flows of Viscous Incompressible Fluids of Finite Element Method

Answer 1

Correct answer is (d) =0

The explanation: The slow flow of a viscous and incompressible fluid in a closed domain is characterized by the following expressions:

Slow (inertial effects are negligible): v.∇v=0.

Viscous: μ≠0.

Incompressible: =0.

It is not a uniform flow; thus, ≠0.