I'm trying to graph the average shear stress in a smooth line as shown in the left graph in the image, but the graph needs to be shear stress x distance, not iterations, like the graph on the right in the image. How do I average the data to get a smoother graph?

I think there are some things I'm not understanding about how solidworks performs flow simulations. For the Iterations graph, why does it take ~80 iterations for the data to level out? And why does my stress at each distance graph report such different numbers at each distance point? I'd say it was due to eddy currents but the flow trajectory views don't show anything but nearly perfect laminar flow

Regarding the iterations, Flow Simulation is an iterative solver. If you were to do a Cut Plot in the preview mode while the solver is running you will see the process of iteration and the flow fields developing, as well as the results eventually stabilizing and converging.

It's an oversimplification of the process but with any iterative solver the process looks like this:

-initial "guesses" for the starting values of each cell are input

-boundary conditions are enforced,

-the solution is performed over and over again (while preserving certain rules like conservation of mass/energy)

It continues to repeat this process until your target goals have reached their convergence tolerance or the solution hits some other arbitrary stop (like a number of iterations limit or calculation time limit) - these can be specified under the "Calculation Control Options"

Assuming this is a steady state analysis then you do not want any of the data before the final iteration. That "vs iterations" graph is simply showing you the history of how a goal converged to its final value.

The other plot looks like maybe an X-Y plot. If you are sampling individual points through space, there will inherently be some noise there. You could take the mean value in Excel if you expect it to be consistent.

If you want to do averaging within flow simulation you can do that. If you create a volume to represent the area you want to average, then you can define a volume goal and choose the "average" criteria for the parameter you want - which will report only the averaged value across that volume. Same can be done for surface goals across a face.

If you need to create some extra "dummy" body to represent a volume to average then you would need to also disable it in the Component Control (so the fluid flows through it as if it's not there)

You may also need additional mesh/cell refinement to smooth out your results, more info on your study setup would probably be necessary for anyone to help further.