wingSegmentType

A segment connects the airfoil of its start element (fromElementUID) with the airfoil of its end element (toElementUID), and the surface of the wing is lofted between them. The segments of a wing follow each other from root to tip; usually, each segment starts at the element at which the previous one ends. Guide curves (guideCurveType) can shape the surface between the airfoils.

Segment coordinates

Positions on a segment, e.g. of spars, ribs or control surfaces, are given in the relative coordinates η (eta) along the span and ξ (xsi) along the chord. They are defined on the chord surface of the segment, the surface between the chord lines of its start and end element. A chord line runs from the leading to the trailing edge of the airfoil as it is placed in the wing, so that a point with the coordinates η and ξ lies at

P(eta, xsi) = (1 - eta) [(1 - xsi) P_LE,from + xsi P_TE,from] + eta [(1 - xsi) P_LE,to + xsi P_TE,to]

where P_LE and P_TE are the leading and trailing edge points of the start element (from) and the end element (to). η runs from 0 at the start element to 1 at the end element, and ξ from 0 at the leading edge to 1 at the trailing edge. Lines of constant η and lines of constant ξ are straight. The points lie on the chord surface, not on the upper or lower surface of the wing; guide curves do not change them. Component segments (componentSegmentType) combine the coordinates of several segments.

Top view of a wing with two segments, each with its own lines of constant eta and xsi in steps of 0.25, eta running along each segment from its start element and xsi from the leading to the trailing edge, and the point eta 0.5, xsi 0.75 in segment 1

The figure shows the coordinates of the two segments of the example below in the top view. Each segment has its own coordinates from 0 to 1. The marked point lies halfway between the root and the kink element (η = 0.5) at three quarters of the chord (ξ = 0.75) of segment 1.

Example

The segments of the wing shown in wingType, from the root to the kink section and from the kink to the tip section:

<segments>
    <segment uID="Wing_segment1">
        <name>Segment 1</name>
        <fromElementUID>Wing_root_element</fromElementUID>
        <toElementUID>Wing_kink_element</toElementUID>
    </segment>
    <segment uID="Wing_segment2">
        <name>Segment 2</name>
        <fromElementUID>Wing_kink_element</fromElementUID>
        <toElementUID>Wing_tip_element</toElementUID>
    </segment>
</segments>

Wing segments from root to tip

Attributes

Name	Type	Use	Description
`@externalDataDirectory`	`xsd:string`	optional	Directory of the external data file
`@externalDataNodePath`	`xsd:string`	optional	Path of the node inside the external data file
`@externalFileName`	`xsd:string`	optional	Name of the external data file
`@uID`	`xsd:ID`	required	UID

Child elements

Name	Type	OccurrenceHow often the element may appear at this place. The schema writes it as minOccurs and maxOccurs on the declaration.	Description
allThe children below may appear in any order. Each may appear at most once.
`name`	`stringBaseType`	[1..1] required	Name
`description`	`stringBaseType`	[0..1] optional	Description
`fromElementUID`	`stringUIDBaseType`	[1..1] required	Element at which the segment starts
`toElementUID`	`stringUIDBaseType`	[1..1] required	Element at which the segment ends
`guideCurves`	`guideCurvesType`	[0..1] optional	Guide curves shaping the surface between the airfoils

wingSegmentType

Attributes

Child elements

Used by

In a dataset · 4 paths

In the schema · 1 declaration