Hi. I'm running axisymmetric round jet into an otherwise stagnant surrounding - incompressible constant temperature with standard k-eps with 2nd order discretuzation and double precision. The jet isssuing from a long (>100 DIA) tube having a fully-developed flow towards the end of it. Jet Re=10^5. I'm getting self-similar solution but it is pretty different from the one suggested in e.g. Schlichting (BL theory) chapter XXIV, i.e. book - b1/2=0.0848x, while I have something about 20% higher. Does anybody have an experience with modelling such free jets? Any suggestions on turb. model? Something?

Standard k-eps give wrong results for round jet (see "Turbulence modeling for CFD" of Wilcox on page 99). For better results you can try to calculate your task with realizable k-eps or k-omega.

thanx