Tj. Craft et al., IMPINGING JET STUDIES FOR TURBULENCE MODEL ASSESSMENT .2. AN EXAMINATION OF THE PERFORMANCE OF 4 TURBULENCE MODELS, International journal of heat and mass transfer, 36(10), 1993, pp. 2685-2697
Four turbulence models are applied to the numerical prediction of the
turbulent impinging jets discharged from a circular pipe measured by C
ooper et al. [Int. J. Heat Mass Transfer 36, 2675-2684 (1993)], Baughn
and Shimizu [ASME J. Heat Transfer 11 1, 1096-1098 (1986)] and Baughn
et al. [ASME Winter Annual Meeting, November 1992]. They comprise one
k-epsilon eddy viscosity model and three second-moment closures. In t
he test cases selected, the jet discharge was two and six diameters ab
ove a plane surface orthogonal to the jet's axis. The Reynolds numbers
were 2.3 x 10(4) and 7 x 10(4), the flow being fully developed at the
discharge plane. The numerical predictions, obtained with an extended
version of the finite-volume TEAM code, indicate that the k-epsilon m
odel and one of the Reynolds stress models lead to far too large level
s of turbulence near the stagnation point. This excessive energy in tu
rn induces much too high heat transfer coefficients and turbulent mixi
ng with the ambient fluid. The other two second-moment closures, adopt
ing new schemes for accounting for the wall's effect on pressure fluct
uations, do much better though one of them is clearly superior in acco
unting for the effects of the height of the jet discharge above the pl
ate. None of the schemes is entirely successful in predicting the effe
cts of Reynolds number. It is our view, however, that the main cause o
f this failure is the two-equation eddy viscosity scheme adopted in al
l cases to span the near-wall sublayer rather than the outer layer mod
els on which the present study has focused.