Aircraft nose noise reduction vortex generator device

Abstract

The invention belongs to the technical field of aircraft aerodynamic design, and relates to an aircraft nose noise reduction vortex generator device. The device comprises 13 vortex generators, the seventh vortex generator is positioned right behind the central circular light window of the spherical machine head pod; the 13 vortex generators are arranged towards the two sides along the rear edge of the central circular light window of the spherical machine head pod by taking the seventh vortex generator as the center; the two vortex generators which are symmetrically arranged are consistent in appearance, and the first vortex generator, the second vortex generator, the third vortex generator, the fourth vortex generator, the fifth vortex generator, the sixth vortex generator and the seventh vortex generator are sequentially arranged from the two sides to the middle. Wherein the seventh vortex generator is shortest in length, and the vortex generators arranged on the two sides of the seventh vortex generator are increased in sequence; a gap is formed between the front end of each vortex generator and the central circular light window; and each vortex generator is arranged along the heading direction.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft aerodynamic design, and relates to an aircraft nose noise reduction vortex generator device. Background Art

[0002] Aircraft noise is mainly the result of high-speed airflow and the turbulence and relative movement of objects in the airflow. The noise sources can be divided into power plant noise, aircraft system noise, body aerodynamic noise, etc.

[0003] Airframe aerodynamic noise is the air flow around the aircraft when it flies at high speed, producing a boundary layer. The higher the speed, the greater the boundary layer transition and separation phenomenon, and the higher the noise sound pressure level produced.

[0004] When air flows through a cavity, self-excited oscillations occur in the cavity. The aerodynamic noise generated by the coupling between the flow field and the acoustic field can cause vibration and fatigue damage to the structure, and even affect the service life of the structure. Therefore, how to control and reduce the aerodynamic noise of the cavity has become a focus of research for scholars at home and abroad. Summary of the invention

[0005] Purpose of the invention: The present invention aims at the aerodynamic noise impact caused by the spherical nose pod of the aircraft with a complex cavity, and provides a vortex generator device that can effectively reduce the noise level of the spherical nose pod with a complex cavity.

[0006] Technical solution:

[0007] An aircraft nose noise reduction vortex generator device, comprising: 13 vortex generators;

[0008] The seventh vortex generator is located directly behind the central circular light window of the spherical nose pod;

[0009] The 13 vortex generators are arranged on both sides along the rear edge of the central circular light window of the spherical nose pod with the seventh vortex generator as the center; the two symmetrically arranged vortex generators have the same appearance, and from both sides to the middle are the first vortex generator, the second vortex generator, the third vortex generator, the fourth vortex generator, the fifth vortex generator, the sixth vortex generator and the seventh vortex generator;

[0010] Among them, the seventh vortex generator is the shortest, and the vortex generators arranged on both sides thereof are longer in length; there is a gap between the front end of each vortex generator and the central circular light window; and each vortex generator is arranged along the heading.

[0011] Furthermore, the top shape of the first vortex generator is consistent with the curvature change of the spherical nose pod, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 57°; the bottom length of the first vortex generator is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0012] Furthermore, the top shape of the second vortex generator is consistent with the curvature change of the spherical nose pod shape, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 52°; the bottom length of the second vortex generator is 208mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0013] Furthermore, the top shape of the third vortex generator is consistent with the curvature change of the spherical nose pod, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 62°; the bottom length of the third vortex generator is 196mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0014] Furthermore, the top shape of the fourth vortex generator is consistent with the curvature change of the spherical nose pod shape, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 71°; the bottom length of the fourth vortex generator is 160mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0015] Furthermore, the top shape of the fifth vortex generator is consistent with the curvature change of the spherical nose pod shape, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 74°; the bottom length of the fifth vortex generator is 110mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0016] Furthermore, the top shape of the sixth vortex generator is consistent with the curvature change of the spherical nose pod shape, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 72°; the bottom length of the sixth vortex generator is 87mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0017] Furthermore, the top shape of the seventh vortex generator is consistent with the curvature change of the spherical nose pod, the leading edge profile is an arc-shaped smooth curve, and the leading edge angle is 57°; the bottom length of the seventh vortex generator is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

[0018] Beneficial Effects

[0019] The present invention designs a vortex generator for reducing noise in the aircraft nose that can effectively reduce aerodynamic noise. For the complex spherical pod in the aircraft nose, the CFD numerical simulation calculation method is used to improve the airflow separation of the spherical pod to a certain extent under most flight conditions such as different pod attitude angles, aircraft angles of attack, and sideslip angles, and has a significant effect on reducing noise in a larger range. The total sound pressure level is reduced by about 5dB to 8dB under different working conditions. In addition, the vortex generator device for reducing noise has the advantages of simple structure, light weight, and small workload for aircraft modification. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention includes 3 drawings, and the drawings and the descriptions of the drawings are as follows:

[0021] Figure 1a is an outline diagram of a first vortex generator;

[0022] Figure 1b is an outline diagram of a second vortex generator;

[0023] Figure 1c is an appearance diagram of a third vortex generator;

[0024] Figure 1d is an outline diagram of a fourth vortex generator;

[0025] Figure 1e is an outline diagram of a fifth vortex generator;

[0026] Figure 1f is an appearance diagram of a sixth vortex generator;

[0027] Figure 1g is an outline diagram of the seventh vortex generator;

[0028] Figure 2 This is a schematic diagram of the installation of a vortex generator device for reducing noise on the nose of an aircraft (top view);

[0029] Figure 3 This is a schematic diagram of the installation of a vortex generator device for reducing noise on the nose of an aircraft (side view);

[0030] Among them: 1-the first vortex generator, 2-the second vortex generator, 3-the third vortex generator, 4-the fourth vortex generator, 5-the fifth vortex generator, 6-the sixth vortex generator, 7-the seventh vortex generator, 8-the spherical nose pod. DETAILED DESCRIPTION

[0031] A head noise reduction vortex generator device of the present invention is described in detail with reference to the accompanying drawings:

[0032] With the development of computational fluid dynamics and aeroacoustics, the research on cavity noise suppression mechanism has become increasingly in-depth, and installing noise reduction devices to suppress noise has become an important measure.

[0033] The nose of the aircraft is a spherical pod with an irregular spherical shape and irregular concave cavities, and it needs to perform multi-axis movements such as roll / pitch during flight. The aerodynamic shape of the aircraft nose is complex. The spherical pod changes the original streamlined aerodynamic shape of the aircraft, has complex cavity flow characteristics, and has a potential threat of aerodynamic noise of the fuselage.

[0034] Therefore, the present invention aims at the spherical nose pod of the aircraft with a complex cavity, and designs a vortex generator that can effectively reduce aerodynamic noise through CFD numerical simulation calculation method in order to achieve the purpose of changing the flow field of the airflow and reducing noise.

[0035] like Figure 1a-1g , Figure 2 and Figure 3 As shown, a head noise reduction vortex generator device is provided, including 13 vortex generator components, the vortex generator is 2mm thick and 30mm high. Figure 2 As shown, the spanwise distance between every two vortex generators is 45 mm.

[0036] The top shape of the first vortex generator 1 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 57°. The bottom length of the first vortex generator 1 is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two first vortex generators 1 are installed symmetrically on the left and right.

[0037] The top shape of the second vortex generator 2 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 52°. The bottom length of the second vortex generator 2 is 208mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two second vortex generators 2 are installed symmetrically on the left and right.

[0038] The top shape of the third vortex generator 3 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 62°. The bottom length of the third vortex generator 3 is 196mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two third vortex generators 3 are installed symmetrically on the left and right.

[0039] The top shape of the fourth vortex generator 4 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 71°. The bottom length of the fourth vortex generator 4 is 160mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two fourth vortex generators 4 are installed symmetrically on the left and right.

[0040] The top shape of the fifth vortex generator 5 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 74°. The bottom length of the fifth vortex generator 5 is 110mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two fifth vortex generators 5 are installed symmetrically on the left and right.

[0041] The top shape of the sixth vortex generator 6 is basically consistent with the curvature change of the spherical nose pod 8, and the leading edge section is an arc-shaped smooth curve with a leading edge angle of 72°. The bottom length of the sixth vortex generator 6 is 87mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. Two sixth vortex generators 6 are installed symmetrically on the left and right.

[0042] The top shape of the seventh vortex generator 7 is basically consistent with the curvature change of the spherical nose pod 8. The leading edge section is an arc-shaped smooth curve with a leading edge angle of 57°. The bottom length of the seventh vortex generator 7 is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading. The seventh vortex generator 7 is located on the symmetry plane of the spherical nose pod 8, and there is only one.

[0043] The present invention is aimed at the complex spherical pod of the aircraft nose. Through the CFD numerical simulation calculation method, a vortex generator that can effectively reduce aerodynamic noise is used. Under most flight conditions such as different pod attitude angles, aircraft angles of attack, and sideslip angles, the airflow separation of the spherical pod is improved to a certain extent, and the noise in a larger range is significantly reduced. The total sound pressure level is reduced by about 5dB to 8dB under different working conditions. In addition, the noise reduction vortex generator device has the advantages of simple structure, light weight, and small workload for aircraft modification.

Claims

1. An aircraft nose noise reduction vortex generator device, characterized in that: include: 13 vortex generators; The seventh vortex generator is located directly behind the central circular light window of the spherical nose pod; The 13 vortex generators are arranged on both sides along the rear edge of the central circular light window of the spherical nose pod with the seventh vortex generator as the center; the two symmetrically arranged vortex generators have the same appearance, and from both sides to the middle are the first vortex generator, the second vortex generator, the third vortex generator, the fourth vortex generator, the fifth vortex generator, the sixth vortex generator and the seventh vortex generator; Among them, the seventh vortex generator is the shortest, and the vortex generators arranged on both sides thereof are longer in length; there is a gap between the front end of each vortex generator and the central circular light window; and each vortex generator is arranged along the heading.

2. The device according to claim 1, characterized in that The top shape of the first vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 57°. The bottom length of the first vortex generator is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

3. The device according to claim 1, characterized in that The top shape of the second vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 52°. The bottom length of the second vortex generator is 208mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

4. The device according to claim 1, characterized in that The top shape of the third vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 62°. The bottom length of the third vortex generator is 196mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

5. The device according to claim 1, characterized in that The top shape of the fourth vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 71°. The bottom length of the fourth vortex generator is 160mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

6. The device according to claim 1, characterized in that The top shape of the fifth vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 74°. The bottom length of the fifth vortex generator is 110mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

7. The device according to claim 1, characterized in that The top shape of the sixth vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 72°. The bottom length of the sixth vortex generator is 87mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

8. The device according to claim 1, characterized in that The top shape of the seventh vortex generator is consistent with the curvature change of the spherical nose pod. The leading edge profile is an arc-shaped smooth curve with a leading edge angle of 57°. The bottom length of the seventh vortex generator is 216mm, the tail height is 30mm, the thickness is designed to be 2mm, and the thickness is uniform along the heading.

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