Rectangular wings

Fig. 6.1. Pressure distribution On a surface of a wing

The leading edge and trailing edge - supersonic, lateral edges and - subsonic on a wing (Fig. 6.1). The influence of lateral edges (pressure equalization between the lower and upper surface) has an effect only in areas and , limited by Mach cones, in difference from subsonic flow where the pressure equalization (influence of lateral edges) occurs all spanwise. Outside of area of influence (surface of a wing ) the flow is similar to flow about flat plate in two-dimensional flow. The pressure factor in any point of wing surface outside of areas of influence of lateral edges is equal

. (6.1)

In the field of influence of lateral edges the factor of pressure is determined

Fig. 6.2.

. (6.2)

(Here wing is considered as a flat plate). The last formula is recorded for case when there is no mutual influence of the right-hand and left-hand lateral edges (Fig. 6.2). This influence appears at such Mach numbers, when the Mach cone of the left-hand (or the right-hand) lateral edge crosses the right-hand (left-hand) lateral edge.

Limit case of mutual influence absence is determined by a condition . Fig. 6.3. shows probable cases of lateral edges mutual influence.

Fig. 6.3.

The factor of pressure in the field of mutual influence of lateral edges is determined by more complex formulae; they are shown in the special literature.

Summarizing distributed pressure we shall define the aerodynamic characteristics.

The following formulas are received for the case when :

; (6.3)

; (6.4)

; (6.5)

; (6.6)

; (6.7)

. (6.8)

At equations for the aerodynamic characteristics for rectangular wings become considerably complicated.

Let's analyze the aerodynamic characteristics.

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