CN108045555B

CN108045555B - Spoiler arranged on front edge of deep open type embedded article cabin

Info

Publication number: CN108045555B
Application number: CN201711237895.0A
Authority: CN
Inventors: 管德会; 张来; 张沛良; 陈振龙; 衣然
Original assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Current assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Priority date: 2017-11-30
Filing date: 2017-11-30
Publication date: 2021-01-19
Anticipated expiration: 2037-11-30
Also published as: CN108045555A

Abstract

The invention relates to a spoiler arranged at the front edge of a deep open type embedded article cabin, and belongs to the technical field of aviation tests. According to the invention, the spoiler is designed, two surfaces of the spoiler are combined by an axis, two ends of the spoiler are provided with relatively sharp end points, one end point is arranged at the front edge of the article cabin at a certain deflection angle, incoming flow in front is supported after impacting the windward surface of the spoiler, and the air flow is far away from the cabin body to reduce the air flow in the cabin, so that the impact force of the air flow and the rear wall of the article cabin is reduced, and the noise reduction effect is achieved; the leeward side of the spoiler should generate a good low-pressure area to attract the high-pressure air in the cabin to flow towards the leeward side of the spoiler and then flow out of the cabin body, a large-scale vortex is formed in the cabin, the stable flowing of the rear wall surface of the object cabin is ensured, and the aerodynamic noise is reduced. The design principle of the invention is clear and easy to realize, the reliability of the design is improved, and the design cost of the turbulence device is greatly reduced.

Description

Spoiler arranged on front edge of deep open type embedded article cabin

Technical Field

The invention belongs to the technical field of aviation tests, and particularly relates to a spoiler arranged at the front edge of a deep open type embedded article cabin.

Background

With the development of aviation technology, some aircraft article equipment needs to be buried. After the cabin door is opened, the rear wall of the object cabin generates serious pneumatic noise, so that the rear wall structure of the object cabin is easy to fatigue damage, and the economic service life of the airplane is seriously shortened. For this reason, it is necessary to design a flow control device that effectively reduces the aerodynamic noise of the rear wall of the product compartment.

The length-depth ratio of the deep open type embedded article cabin is less than or equal to 8.

A great deal of research work is carried out at home and abroad from the viewpoint of raising a shear layer (namely, supporting airflow) to prevent the airflow from impacting the rear wall of an article cabin so as to reduce aerodynamic noise, and the results are applied to several types of airplanes. However, no one has proposed the principle of controlling the flow in the suction-supporting type so far, and no one has summarized the functional relationship of the design of the suction-supporting type spoiler, but the method of designing a large number of samples according to the multi-parameter change rule to perform CFD simulation or wind tunnel test optimization is adopted, so that the workload and the cost are huge.

Disclosure of Invention

The invention aims to provide a spoiler arranged at the front edge of a deep-open type embedded article cabin, which is used for reducing the impact of airflow on the rear edge of the article cabin.

In order to achieve the purpose, the invention adopts the technical scheme that: the spoiler is provided with two smooth curved surfaces which are symmetrical by an axis, is arranged outside the article cabin and is arranged according to spoiler position parameters so as to form a large-scale vortex in the article cabin, wherein the spoiler position parameters comprise a deflection angle theta formed by the spoiler and an air flow direction, a spoiler length L, a spoiler and article cabin front wall distance X, and a spoiler and article cabin exit opening plane height H.

Further, the deflection angle θ formed by the spoiler and the airflow satisfies: theta is 20-30 degrees.

Further, the spoiler length L satisfies: l ═ 1.5 to 2.5 δ/sin θ

Wherein δ is the boundary layer thickness.

Further, the distance X of the front wall of the article compartment satisfies the following condition: x is 0.015 to 0.05a,

wherein a is the length of the goods cabin.

Further, the spoiler and the plane height H of the hatch of the goods cabin meet the following requirements: h ═ 0.43X + 0.46.

After the spoiler of the invention is used for the spoiler with reasonable parameters, a large-scale vortex is formed in the article bin, so that the rear wall flow is stable and easy to realize, the reliability of the design is improved, and the design cost of the spoiler device is greatly reduced.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a schematic view showing a positional relationship between a spoiler and a cargo compartment in the present invention.

Fig. 2 is a diagram showing the effect that the vertical distance H and the lateral distance X of the spoiler do not satisfy the functional relationship of the invention.

Fig. 3 is an effect diagram of the spoiler with an excessively large deflection angle θ.

Fig. 4 is a diagram showing the effect of flow control after the spoiler is properly installed according to the method of the present invention.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the accompanying drawings in the embodiments of the present invention.

As shown in fig. 1, which is a parameter description of the relative position between the spoiler 3 and the cargo compartment in the present invention, the length of the spoiler 3 is defined as L, the deflection angle relative to the exit plane 2 of the cargo compartment is defined as θ, the end points of the spoiler 3 near the front wall 1 of the cargo compartment and the cargo compartment opening are defined as a, the lateral distance between the end point a and the front wall 1 of the cargo compartment is defined as X, and the vertical distance between the end point a and the cargo compartment opening is defined as H. The turbulent boundary layer thickness of the product compartment leading edge 1 is δ, which is known data.

The principle of the suction type flow control generated by the spoiler 3 of the invention is as follows: the design is one spoiler 3, the spoiler 3 is formed by combining two surfaces by one axis, two ends of the spoiler 3 are provided with relatively sharp end points, one end point is arranged at the front edge 1 of the article cabin at a certain deflection angle theta, the front incoming flow is supported after impacting the windward surface (lower surface) of the spoiler 3, and the air flow is far away from the cabin body to reduce the air flow in the cabin, so that the impact force of the air flow and the rear wall of the article cabin is reduced, and the noise reduction effect is achieved. The leeward side (upper surface) of the spoiler 3 should generate a good low-pressure area to attract the high-pressure air in the cabin to flow towards the leeward side of the spoiler 3 and then flow out of the cabin body, a large-scale vortex is formed in the cabin, the stable flowing of the rear wall surface of the object cabin is ensured, and the aerodynamic noise is reduced.

For the design of the position of the spoiler 3 in the invention, the design comprises the following steps:

first, the deflection angle θ is determined. In the control principle of the invention, the suction effect of the leeward side of the spoiler 3 is taken as the main factor, the influence of the spoiler 3 on the aerodynamic characteristics of the whole machine is considered, and the final design is as follows: theta is 20-30 degrees.

In a second step, the length L of the spoiler 3 is determined. In the control principle of the invention, the effect of the suction force of the leeward side and the influence of the spoiler on the aerodynamic characteristics of the whole machine are taken as main factors, and the control principle is finally designed as follows according to the boundary layer thickness delta: l is (1.5-2.5) delta/sin theta.

And thirdly, determining the position relation between the vertical distance H and the transverse distance X. In the control principle of the invention, the suction effect of the leeward side is taken as the main, and the functional relation of the two is finally determined as follows: h is-0.43X +0.46, and assuming that the length of the embedded goods compartment is a, X is preferably 0.015a to 0.05 a.

After the spoiler 3 is arranged according to the principle, the test is carried out on the object cabin of a certain type of airplane, and the effect is very ideal.

As shown in fig. 2, which is a graph showing the adverse effect of the fact that the vertical distance H and the lateral distance X of the spoiler 3 do not satisfy the functional relationship of the present invention, it can be seen that a complex vortex system having two larger vortex systems and one smaller vortex system in the tank is unstable to the flow of the rear wall of the cargo tank.

As shown in fig. 3, which is an adverse effect diagram of the excessive deflection angle θ of the spoiler 2, it can be seen that a plurality of vortex systems are formed in the tank and are distributed unevenly, and a vortex system is also formed at the rear wall of the product tank, and the flow of the vortex system is unstable.

Fig. 4 shows that after the spoiler with reasonable parameters is installed according to the method of the invention, stable lifting vortex is formed in the front edge part of the goods cabin and a large-scale vortex is formed in the goods cabin, so that the rear wall flow of the goods cabin is finally stable.

The design principle of the invention is clear and easy to realize, the reliability of the design is improved, and the design cost of the turbulence device is greatly reduced.

The above description is only for the best mode of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. The utility model provides a set up in spoiler of buried article cabin leading edge in degree of depth open, its characterized in that, the spoiler has two slick and sly curved surfaces symmetrical with the axis and both ends have sharp-pointed extreme point, the spoiler sets up in the outside in article cabin, sets up the spoiler according to spoiler position parameter so that article under-deck forms the major scale swirl, spoiler position parameter includes:

the deflection angle theta formed by the spoiler and the airflow direction satisfies the following conditions: theta is 20-30 degrees;

a length L of the spoiler that satisfies: l is (1.5-2.5) delta/sin theta, wherein delta is the thickness of the turbulent boundary layer at the front edge of the article cabin;

a distance X between the spoiler and the front wall of the goods compartment, the distance X satisfying: x is 0.015-0.05 a, and a is the length of the goods cabin; and

the plane height H between the spoiler and the goods cabin exit port satisfies the following conditions:

H＝-0.43X+0.46。