Question

Which of these statements is true?

(a) The standard k-ε model and the RNG k-ε model are realizable

(b) Neither the standard k-ε model nor the RNG k-ε model is realizable

(c) The standard k-ε model is realizable but not the RNG k-ε model

(d) The RNG k-ε model is realizable but not the standard k-ε model

This question was posed to me by my college director while I was bunking the class.

My doubt is from Turbulence Modelling in chapter Turbulence Modelling of Computational Fluid Dynamics

Answer 1

Correct choice is (b) Neither the standard k-ε model nor the RNG k-ε model is realizable

Easy explanation: Both the standard k-ε model and the RNG k-ε model are not realizable. They do not satisfy the mathematical condition of realizability. Only the realizable k-ε model is realizable.