Blade Definition

In NuMAD, a blade is uniquely defined with the BladeDef object, or blade object for short. As defined in source\numadObjects\BladeDef.m, many of the properties are parameterized by spanwise location. Refer to Blade Class for a complete listing of BladeDef properties.

First and foremost there are stations. A station is an airfoil at a specified span location. The airfoil is partitioned by keypoints, shown in Fig. 1. Various blade properties such as blade.leband, blade.teband, blade.sparcapwidth, and blade.sparcapoffset help to position the keypoints precisely. For example, blade.leband is the arclength from the le keypoint to the keypoint a. Regions are defined between the keypoints as listed in Table 2. An adjacent station helps define these regions as areas. Spanwise lines emanating from each keypoint are connected to the corresponding keypoints on an adjacent station; thus bounding the region with four curves. A suffix of either HP or LP is added to each region name to distinguish regions on the high pressure surface verses the low pressure surface. Other airfoil properties and external blade shape data are defined with the AirfoilDef class and the StationDef object respectively. Usually, the number of stations defined needs to be supplemented for with interpolated stations.

Material properties, layup information, and thicknesses and widths are additionally defined in the MaterialDef, StackDef, and ComponentDef respectively. Refer to the Object Classes, Properties, and Methods for more information.

Fig. 1 Relative locations of the blade keypoints.

Table 2 Region definition by keypoints (TE-Trailing edge, LE-leading edge)

Region Name	Bounding Keypoints
LE	le & a
LE Panel	a & b
Spar	b & c
TE Panel	c & d
TE REINF	d & e
TE Flatback	e & te

Terminology

Term or Variable	Definition
HP	High Pressure
LE	Leading Edge
LP	Low Pressure
TE	Trailing Edge