SUAVE Taper

[Yiren Aaron Shen]

Hello Folks,

I wonder for the SUAVE wing component. Is is possible to define a wing segment that has consistent thickness throughout the span despite width taper? It seems that the width and thickness taper is coupled. There is no way of adding a segmented wing that for example at taper ratio of 0.5 from root to tip for chord, but with consistent thickness? I tried to double the thickness_to_chord ratio for the tip section than that of the root but there is still thickness taper applied. 

Thank you!

Yiren

[Yiren Aaron Shen]

I am appending my script for wing platform definition here. The issue is that it seems that the wing components does not take in the secondary airfoil profile 'nasa-tm4645-tip.dat' and used the root airfoil profile throughout the span. I checked the debugger and I am sure that the airfoil data is loaded correctly. For some reason, the secondary airfoil segment definition did not take in this segment dat file. 

# ------------------------------------------------------------------

# Main Wing

# ------------------------------------------------------------------

wing = SUAVE.Components.Wings.Main_Wing()

wing.tag = 'main_wing'

LE_SWEEP = 65.0

wing.aspect_ratio = 1.8648018648

wing.sweeps.leading_edge = 65.0 * Units.deg #openvsp output65.0

wing.thickness_to_chord = 0.0170008 * 2 # semi-thickness * 2

wing.taper = 0.0

wing.spans.projected = 24.0 * Units.inches

wing.chords.root = 25.734 * Units.inches

wing.total_length = 25.734 * Units.inches

wing.chords.tip = 0.0 * Units.inches

wing.chords.mean_aerodynamic = 17.156 * Units.inches

wing.areas.reference = 0.19927702 * Units['meters**2'] # 2.145 ft2

wing.areas.wetted = 2 * 0.19927702 * Units['meters**2'] # 2.145 ft2

wing.origin = [[0.0, 0.0, 0.0]]

wing.aerodynamic_center = [0.4357624, 0.0, 0.0]

wing.vertical = False

wing.symmetric = True

wing.high_lift = False

wing.vortex_lift = True

wing.high_mach = True

wing.dynamic_pressure_ratio = 1.0

# convert LE Sweep to quarter chord sweep

wing.sweeps.quarter_chord = convert_sweep(wing, old_ref_chord_fraction=0.0, new_ref_chord_fraction=0.25)

# Wing Segments

## segment 1

root_airfoil = SUAVE.Components.Airfoils.Airfoil()

root_airfoil.coordinate_file = './nasa-tm4645-root.dat'

segment = SUAVE.Components.Wings.Segment()

segment.tag = 'Root'

segment.percent_span_location = 0.0

segment.twist = 0.0 * Units.deg

segment.root_chord_percent = 1.0

segment.dihedral_outboard = 0.0 * Units.deg

segment.sweeps.quarter_chord = wing.sweeps.quarter_chord

segment.thickness_to_chord = 0.0170008 * 2

segment.append_airfoil(root_airfoil)

wing.append_segment(segment)

## second

airfoil = SUAVE.Components.Airfoils.Airfoil()

airfoil.coordinate_file = './nasa-tm4645-tip.dat'

segment = SUAVE.Components.Wings.Segment()

segment.tag = 'second'

segment.percent_span_location = 0.75

segment.twist = 0.0 * Units.deg

segment.root_chord_percent = 0.25

segment.thickness_to_chord = 0.0170008 * 2

segment.dihedral_outboard = 0.0 * Units.degrees

segment.sweeps.quarter_chord = wing.sweeps.quarter_chord

segment.append_airfoil(airfoil)

wing.append_segment(segment)

## tip

airfoil = SUAVE.Components.Airfoils.Airfoil()

airfoil.coordinate_file = './nasa-tm4645-tip.dat'

segment = SUAVE.Components.Wings.Segment()

segment.tag = 'tip'

segment.percent_span_location = 1.0

segment.twist = 0.0 * Units.deg

segment.root_chord_percent = 0.0

segment.thickness_to_chord = 0.0170008 * 2

segment.dihedral_outboard = 0.0 * Units.degrees

segment.sweeps.quarter_chord = 0.0 * Units.degrees

segment.append_airfoil(airfoil)

wing.append_segment(segment)

# add to vehicle

wing = wing_segmented_planform(wing)

vehicle.append_component(wing)

Thank you!

Best,

Yiren