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Different turbulence model were also employed for comparing the effect of different turbulence model. Standard K-ε, K-ε Realizable and K-ω turbulence model were used and the results were compared.
3. Results and Discussions
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Contours of turbulent dissipation rate shows about the same trend as the contours the strain rate right after the turning. The region of high turbulence dissipation after the turn is about twice the length of baffle spacing (research literature). The high dissipation rate after the turn is because of the expansion of the fluid.
Figure 10. Wall Yplus
Figure 10 shows the yplus at wall was consistently less than 5. FLUENT documentations mentioned that "the mesh should be made either coarse or fine enough to prevent the wall-adjacent cells from being placed in the buffer layer (yplus = 5~30)". Since the yplus from the model was consistenly less than zero and was in the region of viscous sublayer, the turbulence flow near the wall was resolved properly.
