Analysing a ##C_M## graph (pitching moment data)

[SymNeric]

TL;DR

I need advice on how to compare pitching moment data

Hi guys, I hope everyone is safe and well.

I'm currently nearing the end of my third year dissertation, and I'm looking at analysing pitching moment coefficient (C_M) data over a full range of angles of attack for airfoils with different serrations on the trailing edge. What are things to look for and what would, for instance, a lower value mean? I am aware that a C_M of 0 is a symmetric airfoil and that negative is a nose-down moment etc. but I am unsure how to compare the results from different trailing edges to each other? Attached is one set of data, as an example.

Any and all help/insight is appreciated.

 

[Lnewqban]

Welcome, symneric
Sorry, I can't fully understand your question.
Are you asking about the influence of the pitching moment of a wing over the location of the aerodynamic center of and airfoil or the stability of an airplane?
Are you selecting the best serration option among several types?

Here you can read more about the subject:
https://www.grc.nasa.gov/WWW/K-12/airplane/ac.html

https://en.wikipedia.org/wiki/Pitching_moment

https://www.sciencedirect.com/topics/engineering/pitching-moment

 

[FactChecker]

Just a simple comparison, supposing that the lifts are equal, would say that the more negative pitching moment is a disadvantage since it would require more downward torque from the tail. The graphs you show seem strange to me. They change a lot at both AOA extremes and are flat or slightly increasing over most of the AOA range. That doesn't seem right. I would have expected a more linear, smooth downward slope.