Significance of constants in Std.-ke and Realizable-ke turbulence models
 

Hello everybody,
I am working on heat transfer due to jet impingement in 2D domain. I am validating Holgar Martin's 1977 paper using Fluent 6.2. I was able to validate the results only after changing the value of constant C2=3 in epsilon equation for realizable-ke model. Can anybody say the significance of C2 and formula attached to it in epsilon equation?
thanks for reading...plz do reply:)