CN105197246A - Engine sector-shaped noise-reduction nozzle driven by piezoelectric fiber composite materials - Google Patents

Abstract

A fan-shaped noise-reducing nozzle for an engine driven by a piezoelectric fiber composite material, comprising a fan-shaped nozzle, a double-layer piezoelectric fiber composite material fixedly arranged on the upper and lower surfaces of the nozzle fan blade, and a cross section arranged on the upper and lower surfaces of each layer of piezoelectric fiber composite material. The control module of the finger electrode and the control power supply system; the aircraft applies a reverse voltage to the piezoelectric fiber composite material through the control module and the interdigitated electrode, and the deformed piezoelectric fiber composite material promotes the deformation of the nozzle fan; the invention can actively and quickly Change the penetration of the nozzle fan, reduce the jet noise and ensure a small thrust loss; and the piezoelectric fiber composite material has a fast response rate, small weight, and wear resistance, and can be actively adjusted according to the flight status to achieve effective noise reduction and reduction. Unity with little thrust loss.

Description

Fan-shaped noise-reducing nozzles for engines driven by piezoelectric fiber composites

technical field

The invention relates to a technology in the field of aerospace, in particular to a fan-shaped noise-reducing nozzle of an engine driven by a piezoelectric fiber composite material.

Background technique

Aircraft noise sources can be divided into power system noise, such as noise generated by engine fans, compressors, jets, etc., and non-powered noise, such as high-lift device noise, landing gear noise and auxiliary system noise.

Among them, for the engine, the high-speed airflow at the engine outlet mixes with the free airflow of the atmosphere to form a high-speed turbulent shear layer and generate high-intensity turbulent noise. During take-off and landing, engine jet noise will cause serious noise pollution to the airport and surrounding residents. Based on this, the International Civil Aviation Organization has formulated strict noise airworthiness standards; and in the cruising phase of the aircraft, the engine is required to provide high thrust to avoid thrust loss as much as possible to obtain higher fuel utilization. In the design of advanced aero-engines, it is expected to have a small noise index during the take-off and landing phase of the aircraft, and at the same time reduce the thrust loss of the engine as much as possible in the cruising state.

Using fan-shaped nozzles to replace traditional circular nozzles is a passive engine noise control technology that can increase the turbulent mixing of engine core airflow and atmospheric free airflow to reduce noise, but additional thrust loss will occur. Moreover, conventional fan-shaped nozzles are mostly a compromise design between noise reduction effect and thrust loss, and it is difficult to achieve optimal noise control.

The penetration of the fan-shaped nozzle (the difference between the radius of the tangent circle at the tip of the fan lobe and the tangent circle at the bottom of the fan lobe) is a key parameter for engine noise control, which directly affects the noise control effect. Due to the fixed structure of conventional fan-shaped nozzles, the penetration cannot be adjusted actively, which limits the optimal realization of the noise reduction effect; and the design of fan-shaped nozzles with high penetration will increase the thrust loss of the aircraft in the cruising state, making it difficult to obtain better cruising performance .

After searching the prior art, it was found that Chinese Patent Document No. CN103171757A, published on June 26, 2013, discloses an adaptive trailing edge drive device using piezoelectric fiber composite materials. The piezoelectric fiber composite materials are arrayed through epoxy resin. The piezoelectric fiber composite materials are respectively connected to an independent high-voltage power supply, and the output range of the power supply is -500V～+1500V. However, this technology directly applies voltage to the piezoelectric fiber composite material through an additional power source. When the material size is large, the internal electric field distribution is not uniform, and simultaneous deformation cannot be achieved.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the present invention proposes an engine fan-shaped noise-reducing nozzle driven by a piezoelectric fiber composite material. The piezoelectric fiber composite material is applied to the engine fan-shaped nozzle to realize uniform deformation of the nozzle fan, which can be actively and quickly The penetration of the nozzle vane can be changed to reduce the jet noise while ensuring a small thrust loss.

The present invention is achieved through the following technical solutions:

The invention comprises: a fan-shaped nozzle and several driving devices fixedly arranged on the upper and lower surfaces of the fan petals of the nozzle.

The driving device includes: double-layer piezoelectric fiber composite materials, interdigitated electrodes arranged on the upper and lower surfaces of each layer of piezoelectric fiber composite materials, and a control module connected with the interdigitated electrodes and located at the root of the nozzle fan.

The double-layer piezoelectric fiber composite material includes piezoelectric ceramics and organic polymer materials, wherein the thickness of any layer of piezoelectric fiber composite material is equal to 1/4 to 1/3 of the overall maximum thickness of the nozzle fan.

The width of the double-layer piezoelectric fiber composite material is equal to 1/5-1/4 of the length from the tip to the root of the fan leaf of the nozzle.

The overall area of the double-layer piezoelectric fiber composite material is greater than or equal to 1/3 of the area of the fan petals of the nozzle.

The double-layer piezoelectric fiber composite material is fixedly connected with the nozzle leaf by means of rivets, fastening and bonding.

The piezoelectric ceramics and organic polymer materials satisfy any combination of the following:

1) 1-3 structure, that is, piezoelectric ceramics are one-dimensionally connected, and organic polymer materials are three-dimensionally connected;

2) 2-2 structure, that is, both piezoelectric ceramics and organic polymer materials are two-dimensionally connected.

The fiber cross-section of the piezoelectric ceramic can be round, oval, square or irregular.

The fibers of the piezoelectric ceramics are parallel to the nozzle fan-lobe and point from the root of the nozzle fan-lobe to the tip, so that the nozzle fan-lobe produces an ideal deformation result in the working state to drive the nozzle fan-lobe to deflect.

The fiber length of the piezoelectric ceramic is consistent with the overall length of the double-layer piezoelectric fiber composite material, and the fiber distance is 1/6-1/5 of the fiber length.

The organic polymer material can be selected from high temperature resistant epoxy resin and related suitable polymers, and the length, thickness and width of the material are the same as the whole of the piezoelectric fiber composite material.

The interdigitated electrodes are arranged symmetrically along two directions on the upper and lower surfaces of the piezoelectric fiber composite material, including a pair of opposite-sex main electrodes and several opposite-sex branch electrodes, wherein: a pair of main electrodes are arranged along the double-layer piezoelectric fiber composite material. The branch electrodes are arranged along the width direction of the double-layer piezoelectric fiber composite material, and the electrodes at corresponding positions on the upper and lower surfaces of each layer of piezoelectric fiber composite material are of the same polarity.

The control module applies driving voltages in opposite directions to the double-layer piezoelectric fiber composite materials respectively located on the upper and lower surfaces of the nozzle fan flaps to form opposite electric fields.

The driving voltage range is -500V～+500V.

The drive device produces bending deformation along the fiber length direction of the piezoelectric ceramic under voltage control, drives the nozzle fan flap to bend and deflect outward (inward), and generates radial outward (inward) displacement along the nozzle cross section. Active control changes the penetration of the nozzle fan blade, intensifies the strong mixing of fan flow, core flow and free flow, and reduces the low-frequency noise generated when the airflow is ejected at high speed, so as to reduce noise during take-off and landing and reduce thrust loss during cruise.

technical effect

Compared with the prior art, the present invention applies the piezoelectric fiber composite material to the fan-shaped nozzle of the engine, which can actively and quickly change the permeability of the nozzle fan, reduce the jet noise and ensure a small thrust loss; and the pressure The electric fiber composite material has fast response rate, small weight and wear resistance, and can be actively adjusted according to the flight state to achieve the unity of effective noise reduction and thrust loss reduction.

Description of drawings

Figure 1 is a schematic diagram of the installation of the nozzle fan on the engine;

Figure 2 is a schematic diagram of the installation of the drive device on the nozzle fan;

Figure 3 is a schematic diagram of the orientation of the fiber length of the piezoelectric fiber composite material;

Fig. 4 is a sectional view of a unit piezoelectric fiber composite material;

Figure 5 is a sectional view of interdigitated electrode installation;

Fig. 6 is a working schematic diagram of the driving device when the fan lobe is deflected inward;

Fig. 7 is a working schematic diagram of the driving device when the fan lobe interval is deflected inward and outward;

In the figure: 1 is a fan flap, 2 is a driving device, 3 is a piezoelectric ceramic fiber, 4 is an organic polymer material, 5 is an interdigitated electrode, and 6-9 are electrodes.

Detailed ways

The embodiments of the present invention are described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following implementation example.

Example 1

As shown in FIG. 1 and FIG. 2 , the present invention includes a fan-shaped nozzle and several driving devices 2 fixedly arranged on the upper and lower surfaces of the fan flap 1 of the nozzle.

As shown in Figure 3, the drive device 2 includes: double-layer piezoelectric fiber composite materials, interdigitated electrodes 5 arranged on the upper and lower surfaces of each layer of piezoelectric fiber composite materials, and connected to the interdigitated electrodes 5 and positioned at The control module at the root of the nozzle fan flap 1.

The double-layer piezoelectric fiber composite material includes piezoelectric ceramics 3 and organic polymer materials 4 .

The piezoelectric ceramic 3 and the organic polymer material 4 adopt a 1-3 structure, that is, the piezoelectric ceramic 3 is one-dimensionally connected, and the organic polymer material 4 is three-dimensionally connected.

The fiber section of the piezoelectric ceramic 3 is square.

The fibers of the piezoelectric ceramic 3 are parallel to the nozzle fan 1 and point from the root of the nozzle fan 1 to the tip, and the fiber length of the piezoelectric ceramic 3 is consistent with the overall length of the double-layer piezoelectric fiber composite material.

The length, thickness and width of the organic polymer material 4 are the same as the whole of the piezoelectric fiber composite material.

As shown in Figures 4 and 5, the interdigitated electrodes 5 are symmetrically arranged in two directions on the upper and lower surfaces of the piezoelectric fiber composite material, including a pair of opposite main electrodes 6 and 7 and two opposite branch electrodes 8 and 9, wherein: main electrodes 6 and 7 are arranged along the length direction of the double-layer piezoelectric fiber composite material, branch electrodes 8 and 9 are arranged along the width direction of the double-layer piezoelectric fiber composite material, and each layer of piezoelectric fiber composite material The electrodes at the corresponding positions on the upper and lower surfaces are of the same polarity.

The control module applies driving voltages in opposite directions to the double-layer piezoelectric fiber composite materials respectively located on the upper and lower surfaces of the nozzle fan 1 to form opposite electric fields.

As shown in FIG. 6 , the initial state of the fan lobe permeability of the engine nozzle in this embodiment is 0. When the aircraft takes off and lands, the control module controls the power supply system, and applies voltage to the piezoelectric fiber composite material through the interdigitated electrodes on each fan blade to form an electric field, which makes the piezoelectric fiber composite material bend and deform, and drives the engine fan blade inward. Bending, so that the fan lobe produces a permeability greater than 0, increases the mixing rate of the core flow and the free flow, and reduces the low-frequency noise generated by the jet flow.

When the aircraft is in the cruising state, the control module controls the power supply system to remove the electric field generated by the interdigitated electrodes, so that the piezoelectric fiber composite material does not generate strain, and the nozzle flaps return to the initial state to ensure the thrust requirements in the cruising state.

Example 2

As shown in FIG. 1 and FIG. 2 , the present invention includes: a fan-shaped nozzle and several driving devices 2 fixedly arranged on the upper and lower surfaces of the fan flap 1 of the nozzle.

As shown in Figure 3, the drive device 2 includes: double-layer piezoelectric fiber composite materials, interdigitated electrodes 5 arranged on the upper and lower surfaces of each layer of piezoelectric fiber composite materials, and connected to the interdigitated electrodes 5 and positioned at The control module at the root of the nozzle fan flap 1.

The double-layer piezoelectric fiber composite material includes piezoelectric ceramics 3 and organic polymer materials 4 .

The piezoelectric ceramic 3 and the organic polymer material 4 adopt a 1-3 structure, that is, the piezoelectric ceramic 3 is one-dimensionally connected, and the organic polymer material 4 is three-dimensionally connected.

The fiber section of the piezoelectric ceramic 3 is square.

The fibers of the piezoelectric ceramic 3 are parallel to the nozzle fan 1 and point from the root of the nozzle fan 1 to the tip, and the fiber length of the piezoelectric ceramic 3 is consistent with the overall length of the double-layer piezoelectric fiber composite material.

The length, thickness and width of the organic polymer material 4 are the same as the whole of the piezoelectric fiber composite material.

As shown in Figures 4 and 5, the interdigitated electrodes 5 are symmetrically arranged in two directions on the upper and lower surfaces of the piezoelectric fiber composite material, including a pair of opposite main electrodes 6 and 7 and two opposite branch electrodes 8 and 9, wherein: main electrodes 6 and 7 are arranged along the length direction of the double-layer piezoelectric fiber composite material, branch electrodes 8 and 9 are arranged along the width direction of the double-layer piezoelectric fiber composite material, and each layer of piezoelectric fiber composite material The electrodes at the corresponding positions on the upper and lower surfaces are of the same polarity.

The control module applies driving voltages in opposite directions to the double-layer piezoelectric fiber composite materials respectively located on the upper and lower surfaces of the nozzle fan 1 to form opposite electric fields.

As shown in FIG. 7 , the initial state of the fan lobe permeability of the engine nozzle in this embodiment is 0. When the aircraft takes off and lands, the control module controls the power supply system, and applies opposite voltages to the piezoelectric fiber composite material through the interdigitated electrodes on two adjacent fan lobes to form an opposite electric field, so that the piezoelectric fiber composite material bends and deforms, and the driving phase The fan lobes of the adjacent engines are respectively deflected outward and inward, thereby increasing the mixing rate of the core flow and the free flow, and reducing the low-frequency noise generated by the jet flow.

When the aircraft is in the cruising state, the control module controls the power supply system to remove the electric field generated by the interdigitated electrodes, so that the piezoelectric fiber composite material does not produce strain force, and the nozzle fan flap returns to the original state.

Claims (10)

1. the fan-shaped noise reduction nozzle of driving engine of a piezoelectric fibre composite material driving, it is characterized in that, comprise: fan nozzle and be fixedly installed on some actuating devices of nozzle fan lobe upper and lower surface, this actuating device comprises: the double-deck piezoelectric fibre composite material comprising piezoceramic and high-molecular organic material, the interdigital electrode being arranged in every layer of piezoelectric fibre composite material upper and lower surface and be connected with interdigital electrode and be positioned at the control module that described nozzle fans lobe root.

2. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, is characterized in that, the thickness in monolayer of described piezoelectric fibre composite material equals 1/4 ~ 1/3 of the overall maximum ga(u)ge of described nozzle fan lobe.

3. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, is characterized in that, the width of described piezoelectric fibre composite material equals described nozzle and fans the tip of lobe to 1/5 ~ 1/4 of root depth.

4. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, is characterized in that, the entire area of described piezoelectric fibre composite material is more than or equal to 1/3 of described nozzle fan lobe area.

5. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, is characterized in that, the fibers parallel of described piezoceramic points in described fan lobe and from fan lobe root and fans lobe tip.

6. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, it is characterized in that, the fibre length of described piezoceramic is consistent with the entire length of double-deck piezoelectric fibre composite material, and fiber spacing is 1/6 ~ 1/5 of fibre length.

7. the fan-shaped noise reduction nozzle of driving engine that drives of piezoelectric fibre composite material according to claim 1, is characterized in that, described interdigital electrode in the upper and lower surface of described piezoelectric fibre composite material along both direction symmetry arrangement.

8. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, it is characterized in that, described interdigital electrode comprises a pair different in nature beam electrode and some different in nature branch electrodes, wherein: a pair beam electrode is arranged along described piezoelectric fibre composite material length direction, some branch electrodes are along the arrangement of described piezoelectric fibre composite material Width, and every layer of piezoelectric fibre composite material upper and lower surface correspondence position electrode is homopolarity.

9. the fan-shaped noise reduction nozzle of driving engine of piezoelectric fibre composite material driving according to claim 1, it is characterized in that, described control module applies rightabout driving voltage to the two-layer piezoelectric fibre composite material laying respectively at described nozzle fan lobe upper and lower surface.

10. the fan-shaped noise reduction nozzle of driving engine that drives of piezoelectric fibre composite material according to claim 9, is characterized in that, described drive voltage range Wei ?500V ~+500V.