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montagdude / Xoptfoil

Airfoil optimization with Xfoil
GNU General Public License v3.0
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Minimum / Maximum range for pitching moment? #3

Closed aeolus-aircraft closed 4 years ago

aeolus-aircraft commented 5 years ago

I don't know where else to leave this comment. Is there a way to restrict the range of pitching moments? My designs tend to be extremely low drag but over-optimized to the point that they are unstable in pitching moment at stall angles and Reynolds numbers.

montagdude commented 5 years ago

There are pitching moment constraints to take care of that. For each operating point, you set: moment_constraint_type(n) = setting where n is the operating point number and setting can be 'none', 'specify', or 'use_seed'. If you choose 'specify', then you also need to set the min_moment for that point: min_moment(n) = value where value is the pitching moment coefficient constraint.

By the way, there is a discussion thread on RCGroups. That's how most people ask for help. https://www.rcgroups.com/forums/showthread.php?2095696-XoptFoil-airfoil-optimization-with-XFoil