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Read the file into FLUENT and repeat step 4 and step 5 of this tutorial to set up and solve the problem in FLUENT. The solution should converge in approximately 115 iterations. Plot y+ at the plate as explained in step 6.

(click picture for larger image)

https://confluence.cornell.edu/download/attachments/90745545/07_50yplus3.jpg?version=1

y+ ranges from 29 to 50 in this plot. This is (mostly) outside of the ill-defined Buffer region (5 < y+ < 30) and is thus acceptable.

Now use the Total Surface Heat Flux plot to determine Nu _x . Plot Re vs. Nu and compare with the 30x100 mesh results.

(click picture for larger image)

https://confluence.cornell.edu/download/attachments/90745545/07_gridconv100.jpg?version=1

We can see that the courser mesh produces slightly different results, although they are still reasonable. Some numerical error is introduced when the less-refined 30x50 mesh is used. As one would expect, resolving the boundary layer to the laminar sublayer, which we did with the orignial mesh, produces more accurate results than resolving only to the turbulent region. Resolving to the laminar sublayer is not always a reasonable thing to do, especially at high Reynolds numbers. The results from using the 30 x 50 grid show that a reasonable solution can still be obtained without resolving down to the laminar sublayer.

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Read the file into FLUENT and repeat step 4 and step 5 of this tutorial to set up and solve the problem in FLUENT. The solution should converge in approximately 4550 iterations. Plot y+ at the plate.

(click picture for larger image)

https://confluence.cornell.edu/download/attachments/90745545/07_150yplus2.jpg?version=1

y+ ranges from 0.14 to 0.25 in this plot, well within the laminar sublayer.

Now use the Total Surface Heat Flux plot to determine Nu _x . Plot Re vs. Nu and compare with the 30x100 mesh results.

(click picture for larger image)

https://confluence.cornell.edu/download/attachments/90745545/07_gridconv200.jpg?version=1

This plot shows that the results did not change by increasing the fineness of the mesh. Thus, we can conclude that our 30x100 mesh was good enough. It is also important to verify that the solution does not change by refining the mesh in the streamwise direction. In this case, the mesh in the streamwise direction is already fine enough to eliminate mesh-dependent numerical error.

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