RU2307048C1 - Aircraft - Google Patents

Abstract

FIELD: aviation industry.

SUBSTANCE: proposed aircraft contains fuselage, wing and engine. Fuselage and wing are built using two parabolas. Wing is provided with rods with damping devices in units of fastening to aerodynamic center of fuselage.

EFFECT: improved aerodynamic properties of aircraft.

2 cl, 11 dwg

Description

The invention relates to aviation, to the design of an aircraft with enhanced aerodynamic characteristics due to:

- designing the aircraft fuselage in the form of two parabolas:

Y ₁ = K ₁ X ^1/2 ; Y ₂ = 2R ₀ + K ₂ X ^1/2 ;

touching a circle of radius R≥R ₀ for a transport aircraft and R≤R ₀ for a fighter;

- design of the wing of the aircraft of small elongation, a larger area.

Known aircraft with a carrier fuselage containing a wing, an engine, a fuselage whose width is significantly greater than its height, has a concave cross-sectional shape of the fuselage, its lower surface of the flattened part of the fuselage is set at an angle to the longitudinal plane equal to or more than 4 °, preferably 7 ° [one].

The disadvantage of this design is the gutter, which creates turbulence leading to vibration. The upper and lower surfaces of the fuselage are linear and have little participation in the formation of lifting force, and the deviation of the fuselage from the annular shape reduces its strength.

A known propeller / wing blade, ... / [2, 3], where the front and rear edges are formed in the form of two parabolas:

Y ₁ = K ₁ X ^1/2 ; Y ₂ = 2R ₀ + K ₂ X ^1/2 . The profile of the lower and upper lobes is formed by the intersection of two parabolas:

Y ₃ = K ₃ X ^1/2 ; Y ₄ = 2R ₀ + K ₄ X ^1/2 , while the planes intersect at an acute angle at the leading edge.

The disadvantage of this design is that the blade is designed for rotation, which imposes on it individual design differences from a fixed wing.

SUMMARY OF THE INVENTION

The aircraft fuselage is little involved in creating lift, although its area is commensurate with the area of the wings. To increase the lifting force, the lower and upper surfaces of the fuselage are designed according to the formulas of two parabolas:

Y ₁ = K ₁ X ^1/2 ; Y ₂ = 2R ₀ + K ₂ X ^1/2 ;

tangent to a circle of radius R≥2R ₀ for a transport aircraft / FIG.1/ and R≤2R ₀ for a fighter / FIG.4/, the center of which is located at a distance R = 2 / 3L, where L is the projection of the fuselage length on the X coordinate The coefficients K ₁ and K _{2 are} calculated by the formulas:

K ₁ = Y ₁ A / X _1A ^1/2 ; K ₂ = (Y _2B -2R ₀ ) / X _2B ^1/2 ;

where point A is the intersection point of the perpendicular reconstructed from point l with the line of angle of attack α. Point A is the bottom point of a circle of radius R, which is deposited on the restored perpendicular; the top point of intersection of a circle of radius R with a perpendicular will be point B - the point of intersection of the parabola U ₂ with the circle. To find the points of tangency of parabolas U ₁ , U ₂ with a circle of radii R, the initial data for constructing the fuselage are set:

- angle of attack α≥7 °;

- radii R ₀ and R;

- projection of the length of the fuselage on the X-L coordinate;

- the projection value l≤2 / 3L.

Determining the coefficients K ₁ and K ₂ conduct parabolas U ₁ and U ₂ : this will be the fuselage profile / FIG. 1, FIG. 4 /, which resembles the wing profile.

The wing plays a major role in aircraft lift; its length, area, shape affect the lifting force and determine the cost [3].

When designing an airplane wing, a parabola is used. The leading edge of the wing is formed by a parabola:

Y ₁ = K ₁ X ² ; or Y ₂ = K ₂ X ^1/2 ; touching a circle of radius R / FIG.7, FIG.8 /, or an ellipse [4] with the parameters of the major and minor axis 2A, 2B, respectively / FIG.9, FIG.10 /; the center of the circle and the center of the ellipse in this case are separated from the origin by an amount l≤2 / 3L, where

L is the projection of the wing length on the X coordinate.

Initially, the following values are set:

- L - projection of the length of the wing on the coordinate X;

- α is the angle of attack; for high-speed aircraft - α≥35 °, for low-speed - α≥10 °;

- R is the radius of the circle;

- 2A, 2B - parameters of the ellipse / main axis parallel to the axis of the fuselage /;

- projection value l≤2 / 3L;

- M - the length of the wing at the junction with the fuselage.

We find the values of the coefficients K ₁ and K ₂ according to the formulas:

K ₁ = Y _1A / X _1A ² ; K ₂ = Y _2A / X _2A ^1/2 ; where Y _1A , X _1A , Y _2A , X _2A are the coordinates of point A - the tangent points of the parabolas Y ₁ , Y ₂ with a circle or with an ellipse / FIG.7 ÷ FIG.9 /. In some cases, the large axis of the ellipse can be shifted forward by an amount c≤2 / 3a, to increase the wing area / FIG.6, FIG.10 /. The wing is equipped with flaps /FIG.3 - 3, FIG.6 - 3, FIG.7 ÷ FIG.10 - 1 /, and can be equipped with slats /FIG.9 - 2 /. The transverse profile of the wing is formed by the intersection of two parabolas: Y ₃ = K ₃ X ^1/2 ; Y ₄ = K ₄ X ^1/2 + 2R ₀ ; / FIG. 1, FIG. 4 /. The coefficients K ₃ , K ₄ are selected from the values of K ₃ ≥0.7; K ₄ ≥ / 0.2 ÷ 0.8 / K ₃ . The leading edge is rounded with a radius R≥R ₀ , to improve streamlining. To reduce longitudinal vibrations, the longitudinal profile of the wing is formed along a parabola: Y ₅ = K ₅ X ^1/2 ; where K ₅ ≥0.7; the end of the wing has a bend at an angle β = 60 ° to reduce inductive vibrations / FIG.2, FIG.5, FIG.11 /. The wing of the aircraft is equipped with rods / FIG.2-1, FIG.3-1, FIG.5-1, FIG.6-1 /, which enclose the end and middle of the wing with a triangle; the rods are connected to the fuselage with damping devices at point 2. This design allows you to:

- to compensate for the longitudinal vibrations of the wings;

- reduce longitudinal and transverse vibrations;

- transmit the impulse of lift to the aerodynamic center of the fuselage.

In FIG.1, FIG.4 shows the fuselage profile of a transport aircraft and a fighter, respectively. In FIG.2, FIG.5 shows the profile / front / aircraft transport and fighter, respectively. FIG.3, FIG.6 depicted in plan transport aircraft and fighter, respectively. FIG. 7 and FIG. 8, FIG. 9 and FIG. 10 show the principle of constructing a wing using a parabola: Y ₁ = K ₁ X ² ; and Y ₂ = K ₂ X ^1/2 tangent to a circle of radius R and an ellipse /FIG.9/ shifted forward by a value of c≤2 / 3a, /FIG.10/. Figure 11 shows the longitudinal profile of the wing.

CALCULATION OF THE FUSELAGE AND WING OF THE PLANE

The parabolic shape of the fuselage creates increased pressure on the lower edge of the fuselage and rarefaction on the upper edge when the angle of attack α≥7 °; as a result, an additional lifting force is created, proportional to the angle of attack, the length and diameter of the fuselage.

Comparative tests carried out on the fabricated model at R = 2R ₀ showed that the lifting force increases by about 10% compared to [1].

The lifting force of the wing is created by increasing the pressure on the lower edge of the wing and by vacuum on the upper edge of the wing. The lift is proportional to the angle of attack / α ⁷ ≥7 ° / of the wing, the elongation of the wing and its area.

Tests performed on the wing model at 2R = D showed that the lift increases by about 15% compared to [3], while reducing its length by 1/5.

Tests for measuring free wing vibrations using a longitudinal parabolic shape of the wing and the rod, covering the end and middle of the wing with a triangle, showed a decrease in longitudinal and transverse vibrations by more than 50% compared to [3].

INFORMATION SOURCES

1. Patent 20896455 of September 24, 1994

2. Patent 2228882 of May 20, 2004.

3. Wing - “The BIG Soviet Encyclopedia”, Volume 13. M .: Soviet Encyclopedia.

4. Handbook of mathematics. M .: State Publishing House. technical lit. 1987 year

Claims (2)

1. Aircraft containing a wing, an engine carrying the fuselage, characterized in that to increase the lifting force, the lower and upper surfaces of the fuselage of the aircraft are formed by parabolas according to two formulas Y ₁ = K ₁ X ^1/2 ; Y ₂ = K ₂ X ^1/2 + 2R ₀ , which touch a circle of radius R≥2R ₀ - for a transport aircraft and R≤2R ₀ - for a fighter, the center of which is located at a distance l≤2 / 3L, where L is the projection of length aircraft fuselage at coordinate X; initially set values: angle of attack α≥7 °; value l≤2 / 3L; radii R ₀ and R; L is the projection of the length of the fuselage of the aircraft on the X coordinate; the coefficients K ₁ and K _{2 are} calculated by the formulas K ₁ = Y _1A / X _1A ^1/2 ; K ₂ = (Y _2B -2R ₀ ) / X _2B ^1/2 , where X _1A , Y _1A , X _2B , Y _2B are the calculated coordinates of the points A and B of tangency of the parabola with a circle of radius R ₀ . 2. The aircraft according to claim 1, characterized in that the wing is made with a leading edge formed by a parabola Y ₁ = K ₁ X ² or Y ₂ = K ₂ X ^1/2 , tangent to a circle of radius R or an ellipse with parameters 2a, 2b; the centers of the circle and ellipse are located at a distance l≤2 / 3L, where L is the projection of the wing length on the X coordinate; while initially setting the following values: L is the projection of the wing length on the X coordinate; α is the angle of attack of the wing; M is the length of the junction of the wing with the fuselage; l≤2 / 3L - the value of the projection of the center of the circle, ellipse on the X coordinate; the coefficients K ₁ and K _{2 are} calculated by the formulas K ₁ = Y _1A / X _1A ² ; K ₂ = Y _2A / X _2A ^1/2 ; where A is the point of contact of the parabola with a circle or ellipse, the coordinates of which are calculated; the longitudinal profile of the wing is formed by the parabola Y = KX ^1/2 , where K≥0.7, and serves to reduce longitudinal vibrations; the end of the wing has a bend at an angle β≥60 ° to reduce inductive vibrations; end and middle of wing covered by rods; the rods of two wings have a joint mounting unit with damping devices and are attached to the fuselage at the point of the aerodynamic center of the aircraft to reduce longitudinal and transverse vibrations.

Images