We check mass conservation and boundary conditions. We can check mass conservation by going into Fluent under fluxes and selecting mass flow rate.
For mass conservation to be satisfied, we expect the mass flow rate to be 0. The net mass flow rate here is negligibly small and so mass is conserved.
We now compare the results of the original coarse mesh to a more refined mesh. The refined mesh has 900901 cells. The sizing near the leading and trailing edges has been decreased to 5e-3 ft and 7.5e-3 ft respectively. The face sizing on the middle top of the wing and the bottom is .01 ft.The pressure distribution over the wing is shown below.
We can qualitatively compare the pressure coefficient contours from Fluent (right) with those from NASA. Our mesh is somewhat less refined away from the wing, made clear by the rough contours of pressure on the symmetry plane.
We compare the drag coefficient and lift coefficient to those from NASA's WIND simulation:
For refined mesh 2 the grid was changed from coarse relevance center to medium relevance center with the leading edge face and trailing edge face cell sizes further refined. The middle face on the top wing surface and the bottom wing surface sizings were also refined. The body of influence's size was changed to be .0075 ft.
Note: You can improve the results by accounting for the variation in the viscosity of air with temperature using the Sutherland model.