BWB Updates - #1259
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…wo fuselage points, which are overwritten anyway.
…they may not be there.
| historical_name={ | ||
| 'GASP': 'INGASP.CROOTW', | ||
| 'FLOPS': 'WTIN.XLW', | ||
| 'FLOPS': 'WTIN.XLOUT', |
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XLOUT isn't a FLOPS input, but instead an intermediate calculated value (not part of WTIN namelist). Put "XLOUT" as a comment here for now
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| ref_diameter = 0.5 * (max_height + max_width) | ||
| planform_area = max_width * (length + root_chord / rear_spar_percent_chord) / 2.0 | ||
| planform_area = max_width * (length + root_chord) / 2.0 |
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This change means that Aviary doesn't match the FLOPS equations directly anymore, and messes up converting FLOPS files. root_chord, previously XLW (and a FLOPS input) has been redefined to match XLOUT (an intermediate FLOPS calculation) which makes replicating a FLOPS case require hand-calculating this new value and adding it to the CSV. Why?
| add_aviary_input(self, Aircraft.Fuselage.MAX_WIDTH, units='ft') | ||
| add_aviary_input(self, Aircraft.Fuselage.MAX_HEIGHT, units='ft') | ||
| add_aviary_input(self, Aircraft.Wing.ROOT_CHORD, units='ft') | ||
| self.add_input( |
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Why add a variable for RSPSOB to the hierarchy if we are simplifying the equations to no longer use it?
This was motivated by a confusion about Aircraft.Wing.ROOT_CHORD as defined for the BWB, which was not the root chord because it stopped at the rear spar instead of the trailing edge, meaning it is not the chord at that location. I just took another look at these variables in the Fortran code, and I think the correct way to address this is to add WTIN.XLW as a new separate variable in the hierarchy. This is defined in FLOPS as the "Side Wall Length". It is computed by both simple and detailed cabin design. I should restore the output there to XLW, and then compute root chord in a separate simple component (XLOUT, not a FLOPS input). This will restore the ability to specify XLW (which would become |
| add_meta_data( | ||
| Aircraft.Fuselage.CABIN_SIDEWALL_LENGTH, | ||
| meta_data=_MetaData, | ||
| historical_name={ | ||
| 'GASP': None, | ||
| 'FLOPS': 'WTIN.XLW', | ||
| }, | ||
| units='ft', | ||
| desc='Outboard wall of the passenger cabin in a BWB.', | ||
| default_value=0.0, | ||
| ) |
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It doesn't look like this variable gets used anywhere? Having a variable in the hierarchy that does nothing is worse than not having it at all in my opinion
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It doesn't look like this variable gets used anywhere? Having a variable in the hierarchy that does nothing is worse than not having it at all in my opinion
Done. I forgot to remove that when we decided to postpone supporting this way f specifying the model.
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Summary
Aircraft.Wing.ROOT_CHORDto go from leading edge to trailing edge instead of ending at the rear spar.Aircraft.BWB.REAR_SPAR_PERCENT_CHORD_ROOTandAircraft.BWB.REAR_SPAR_PERCENT_CHORD_CENTERLINE.Aircraft.BWB.WING_ROOT_INDEX.Related Issues
Backwards incompatibilities
None
AI Usage
Disclose any AI usage in this PR, including models used and files affected.