Acoustic liner, manufacturing method, power propulsion system, noise reduction method and acoustic liner unit

Abstract

The invention relates to an acoustic liner, a manufacturing method, a power propulsion system, a noise reduction method and an acoustic liner unit. Wherein the acoustic liner unit comprises a plurality of acoustic liner units, and each acoustic liner unit comprises a shell which defines an accommodating cavity; the adjacent acoustic liner units can be connected through respective shells; one end of the accommodating chamber in the length direction is an open end for sound waves to enter, and the other end of the accommodating chamber is a closed end, so that the sound waves are processed in the acoustic liner unit; the acoustic lining element is arranged in the containing cavity, a first cavity is limited by the acoustic lining element, a first pore plate structure and a second pore plate structure are arranged at the two ends of the first cavity in the length direction respectively, the first pore plate structure is located on one side of the opening end of the containing cavity, and the second pore plate structure is located on the other side of the opening end of the containing cavity. The second pore plate structure is located on one side of the closed end of the containing cavity, and in the length direction of the containing cavity, the acoustic lining element and the shell can move relative to each other.

Description

Technical Field

[0001] The invention relates to an acoustic lining component, a manufacturing method, a power propulsion system, a noise reduction method and an acoustic lining unit. Background Art

[0002] Power propulsion systems, such as gas turbine engines, are common in civil aviation engines such as turbofan engines. Figure 1 As shown, the inlet airflow direction is O1. The outside atmosphere first passes through the air intake nacelle A equipped with the acoustic liner device A1, then flows through the large-sized fan 1000, and then is divided into two airflows, a and b. Part a is discharged through the outlet of the fan 1000; part b is the main channel airflow, which is pressurized by the supercharger stage 2000 and the high-pressure compressor 3000 in turn, and becomes high-temperature, high-pressure combustion gas after combustion in the combustion chamber 4000, and then expands and works in the high-pressure turbine 5000 and the low-pressure turbine 6000, and is discharged from the outlet 7000. The engine rotating shaft is 1500, the high-pressure compressor and the high-pressure turbine are connected by the shaft 8000, and the fan, the supercharger stage and the low-pressure turbine are connected by the shaft 9000.

[0003] The problem of civil aviation engine noise poses an important issue for the continuously growing air transport industry. The noise level is directly related to the acquisition of engine airworthiness certification. The noise level of large civil aircraft is one of the important contents of airworthiness certification. The noise certification standards are constantly changing over time. Annex 16 of the International Civil Aviation Organization (ICAO) has made detailed technical specifications for aircraft noise certification. This technical specification adopts the "Effective Perceived Noise Level" (EPNL) and considers three certification benchmark conditions: Sideline, Cutback, and Approach. EPNL is used to quantify aircraft noise and consider the perceived annoyance based on noise measurement. Approach: The state of the aircraft preparing to land on the runway. The airworthiness standards of different aircraft are different. The meaning of each condition is: flyover: the state of the aircraft taking off and rolling for a certain distance, and the airworthiness standards of different aircraft are different; sideline: the state of the aircraft with the highest noise level after leaving the ground, and the airworthiness standards of different aircraft are different; sound pressure level (Sound Power Level) refers to the logarithm of the ratio of sound power to reference sound power multiplied by 10, in decibels. Blade passing frequency (BPF): the noise frequency caused by the blade passing through the tongue of the volute, also known as the fundamental frequency. Figure 2 As shown in the figure, the fan is a typical fluid machine. The airflow flows between the rotating rotor and the stator blade row, generating strong single-tone noise and broadband noise. The fan blades of aircraft engines are widely designed with a small number of blades and a wide chord length. The working points that are most concerned about external field noise are approach landing and takeoff. The blade tip Mach number is at subsonic blade tip speed. The fan noise spectrum is characterized by the blade passing frequency single tone and its harmonics superimposed in the broadband noise spectrum.

[0004] Acoustic lining is a common means of controlling turbine noise. The structure of acoustic lining can include single-degree-of-freedom acoustic lining, double-degree-of-freedom acoustic lining and multi-degree-of-freedom acoustic lining. Single-degree-of-freedom acoustic lining is the earliest form of honeycomb acoustic lining structure, which is composed of perforated plate, honeycomb layer core and rigid back plate. This structure has the advantages of simple process, small structure thickness, convenient structure layout, etc., and is widely used. Double-degree-of-freedom acoustic lining structure includes two honeycomb cores superimposed, that is, it is composed of perforated plate, honeycomb core, middle layer, honeycomb core and back plate. The middle layer can adopt perforated plate, metal mesh, sound-absorbing film with micro holes, embedded sound-absorbing structure and other structures. The embedded sound-absorbing structure can realize non-equal height design according to acoustic needs. Double-degree-of-freedom acoustic lining increases the weight and production cost of the acoustic lining, but the double-degree-of-freedom acoustic lining uses two resonators in series, which can broaden the sound absorption frequency band of the acoustic lining and significantly reduce noise. The multi-degree-of-freedom sound-absorbing structure is to change a single-layer honeycomb into a multi-layer honeycomb, and add a layer of porous plate between each honeycomb layer. However, this sound-absorbing structure has certain problems in use. For example, when the micro-perforated plate is bonded to the honeycomb core material, it is necessary to ensure that the holes are not blocked during the bonding process. In addition, the mechanical properties of the multi-degree-of-freedom sound-absorbing sound lining are greatly reduced during the design and preparation process. At the same time, the addition of the micro-perforated plate has greatly increased the weight of the material itself. Therefore, a porous material diaphragm intermediate layer can be set in the honeycomb core to avoid excessive weight and improve the acoustic performance of the sound lining. The sound-absorbing principle of the sound lining can be regarded as a combination of a large number of Helmholtz resonance cavities, taking the simplest degree-of-freedom sound lining as an example. The acoustic resistance is determined by the micropores, and the size of the resonance cavity determines its resonant frequency, that is, the acoustic reactance. After the sound wave of a specific frequency enters the honeycomb cavity through the small holes on the perforated plate, it will resonate, so that the sound energy is converted into internal energy and consumed. In this way, the two cooperate to achieve the purpose of noise reduction at a specific frequency.

[0005] The schemes and concepts for improving the sound-absorbing effect of the sound lining include the panel hole structure design, the honeycomb core structure design and the addition of other sound-absorbing structures. It is also possible to set a porous material lining core and increase the layer structure in the honeycomb core to improve the noise reduction performance, as well as set a multi-section diaphragm structure, absorber, lining core inside the honeycomb core and set a perforated plate, cotton felt sound absorption and other layer structures between the panel and the core material.

[0006] However, the inventors have found that due to the existence of airworthiness noise regulations, the low-noise design of the fan is required to take into account as many operating conditions as possible, such as the aforementioned sideline, flyover, and approach conditions. However, the current sound lining design can only take one main fundamental frequency as the noise reduction target each time, and through forward optimization iterative design, take into account the fundamental frequencies corresponding to other operating conditions as much as possible to obtain a local optimal solution for the total noise. Such noise reduction effect needs to be improved.

[0007] Therefore, the art needs an acoustic lining component, a manufacturing method, a power propulsion system, a noise reduction method and an acoustic lining unit, so that the acoustic lining can take into account the noise reduction effect of the fundamental frequency corresponding to more working conditions. Summary of the invention

[0008] An object of the present invention is to provide an acoustic lining.

[0009] Another object of the present invention is to provide a manufacturing method.

[0010] Another object of the present invention is to provide a power propulsion system.

[0011] Another object of the present invention is to provide a noise reduction method.

[0012] Another object of the present invention is to provide a sound liner unit.

[0013] According to one aspect of the present invention, a sound lining component includes a plurality of sound lining units, each of which includes: an outer shell defining a accommodating chamber; adjacent sound lining units can be connected through their respective outer shells; one end of the accommodating chamber in the length direction is an open end for sound waves to enter, and the other end is a closed end so that the sound waves are processed inside the sound lining unit; a sound lining element is arranged in the accommodating chamber, the sound lining element defines a first chamber, and the first chamber is respectively provided with a first orifice plate structure and a second orifice plate structure at both ends in the length direction, the first orifice plate structure is located on one side of the open end of the accommodating chamber, and the second orifice plate structure is located on one side of the closed end of the accommodating chamber, wherein the sound lining element and the outer shell can be relatively displaced in the length direction of the accommodating chamber.

[0014] In the scheme of the sound lining parts introduced above, the outer shell of the sound lining unit and the sound lining element can be relatively displaced in the length direction, so that the cavity depth of the resonance cavity that plays a sound-absorbing role can be adjusted according to different working conditions, so that different cavity depths correspond to different working conditions, thereby corresponding to different target noise reduction frequencies. In this way, the same sound lining can achieve targeted noise reduction processing for specific noise frequencies under different working conditions, so that the sound lining can take into account the fundamental frequencies corresponding to various working conditions, thereby improving the noise reduction effect.

[0015] In one or more embodiments of the acoustic lining component, the acoustic lining unit provides an acoustic channel including from the first orifice plate structure through the first chamber, the second orifice plate structure to the closed end of the accommodating chamber. In the length direction of the accommodating chamber, the acoustic lining element and the outer shell can be relatively displaced, and the first orifice plate structure of the acoustic lining element can be displaced to the outside of the open end of the outer shell, so that the distance between the second orifice plate structure and the closed end of the outer shell can be variable to change the length of the acoustic channel.

[0016] In one or more embodiments of the acoustic liner member, the acoustic liner unit further comprises a base, wherein the base is located outside one side of the closed end of the shell, and adjacent acoustic liner units can be connected via their respective bases.

[0017] In one or more embodiments of the acoustic lining member, the base is provided with a driving portion, and the driving portion is connected to the acoustic lining element to drive the acoustic lining element and the shell to be able to move relative to each other.

[0018] In one or more embodiments of the acoustic liner, the driving portion comprises a driving rod, one end of which is connected to the second orifice plate structure of the acoustic liner element.

[0019] In one or more embodiments of the acoustic liner, the base is provided with a first magnetic member, and adjacent acoustic liner units can be magnetically connected via the first magnetic member of the respective bases.

[0020] In one or more embodiments of the acoustic lining component, an elastic member is further included, wherein the elastic member is respectively connected to the outer shell and the acoustic lining element, and when the acoustic lining element and the outer shell are relatively displaced in the length direction of the accommodating chamber, the elastic member can provide a buffering effect.

[0021] In one or more embodiments of the acoustic liner, the shell is provided with a second magnetic member, and adjacent acoustic liner units can be magnetically connected via the second magnetic members of their respective shells.

[0022] In one or more embodiments of the acoustic liner, the cross-sections of the shell and the acoustic liner element are both hexagonal.

[0023] According to another aspect of the present invention, a method for manufacturing an acoustic lining member is provided to manufacture an acoustic lining member as described in any one of the above items.

[0024] In one or more embodiments of the manufacturing method, the manufacturing method comprises: manufacturing the plurality of independent acoustic lining units; and assembling and connecting the plurality of acoustic lining units to form the acoustic lining member.

[0025] A power propulsion system according to another aspect of the present invention comprises any one of the above-mentioned acoustic lining components.

[0026] In one or more embodiments of the power propulsion system, the power propulsion system is a gas turbine engine, and the acoustic lining is disposed in a nacelle of the gas turbine engine.

[0027] According to another aspect of the present invention, a noise reduction method for a power propulsion system adopts the sound lining member described above, and the noise reduction method includes: in a first operating condition of the power propulsion system, the relative position of at least a part of the sound lining elements of the sound lining unit and the outer shell in the length direction of the accommodating chamber is set to a first position; in a second operating condition of the power propulsion system, the relative position of at least a part of the sound lining elements of the sound lining unit and the outer shell in the length direction of the accommodating chamber is set to a second position.

[0028] In one or more embodiments of the noise reduction method, the sound lining unit where the sound lining element which is set to the second position in the second working condition is located is the same sound lining unit as the sound lining unit where the sound lining element which is set to the first position in the first working condition is located.

[0029] According to another aspect of the present invention, a sound lining unit is used for a sound lining member, and the sound lining unit includes: an outer shell, which defines a accommodating chamber; adjacent sound lining units can be connected through their respective outer shells; one end of the accommodating chamber in the length direction is an open end for sound waves to enter, and the other end is a closed end so that the sound waves are processed inside the sound lining unit; a sound lining element is arranged in the accommodating chamber, and the sound lining element defines a first chamber, and the first chamber is respectively provided with a first orifice plate structure and a second orifice plate structure at both ends in the length direction, the first orifice plate structure is located on one side of the open end of the accommodating chamber, and the second orifice plate structure is located on one side of the closed end of the accommodating chamber.

[0030] Wherein, in the length direction of the accommodating chamber, the acoustic lining element and the shell can be relatively displaced. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0032] Figure 1 It is a schematic diagram of the structure of a gas turbine engine.

[0033] Figure 2 It is a schematic diagram of the fan subsonic noise characteristics of a turbofan engine.

[0034] Figure 3 It is a schematic diagram of a top view of an acoustic lining member according to an embodiment.

[0035] Figure 4 It is a schematic diagram of a side view of an acoustic lining member according to an embodiment.

[0036] Figure 5A , Figure 5B It is a schematic structural diagram of a single acoustic lining unit of an acoustic lining member according to an embodiment.

[0037] Fig. 6A , Figure 6B It is a structural schematic diagram showing that the relative position of the acoustic lining element of a single acoustic lining unit of an acoustic lining member of an embodiment and the outer shell is in a first position.

[0038] Fig. 7A , Figure 7B It is a structural schematic diagram of a single acoustic lining unit of an acoustic lining member in an embodiment in which the relative position of the acoustic lining element and the shell is in the second position.

[0039] Figure 8 It is a flow chart of a noise reduction method for a power propulsion system according to an embodiment.

[0040] Fig. 9 It is a schematic block diagram of closed-loop control of a noise reduction method according to an embodiment.

[0041] Fig.10 It is a schematic structural diagram of an actuator cylinder that drives a driving rod of an acoustic lining member according to an embodiment.

[0042] Fig.11 It is a flow chart of a noise reduction method for a power propulsion system according to another embodiment.

[0043] Reference numerals:

[0044] 10- Acoustic Lining

[0045] 1- Acoustic Liner Unit

[0046] 11- Shell

[0047] 111-Accommodation chamber

[0048] 1111-Open end

[0049] 1112-Closed end

[0050] 112-Second magnetic member

[0051] 12- Acoustic lining element

[0052] 121-First Chamber

[0053] 1211-First orifice plate structure

[0054] 1212-Second orifice plate structure

[0055] 13- Base

[0056] 131-first magnetic member

[0057] 14-Driver

[0058] 141-Drive rod

[0059] 15-Elastic parts

[0060] 20-Actuator. DETAILED DESCRIPTION

[0061] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0062] At the same time, the present application uses specific words to describe the embodiments of the present application, such as "one embodiment", "an embodiment", and / or "some embodiments" to refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" mentioned twice or more in different locations in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0063] It is understood that flow charts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that, according to the actual situation, the previous or following operations are not necessarily performed precisely in order. Other operations may also be added to these processes, or one or more operations may be removed from these processes.

[0064] The acoustic lining components described in the following embodiments are applied to gas turbine engines, specifically, the nacelle of a turbofan engine as an example, but are not limited to this. They are applicable to all power propulsion systems, including power propulsion systems with fans, blades, propeller fans, etc., and are not limited to gas turbine engines. For example, they may be a hybrid propulsion system including a gas turbine engine, or a purely electrically driven power propulsion system with fans, blades, and propeller fans to reduce fan noise and / or intake noise.

[0065] refer to Figure 3 , Figure 4 as well as FIG. 5A to FIG. 7B As shown, in some embodiments, the acoustic lining member 10 may include a plurality of acoustic lining units 1 assembled together.

[0066] refer to Figure 5A , Figure 5B as well as Fig. 6A , Figure 6BAs shown, each acoustic liner unit 1 may include a shell 11 and an acoustic liner element 12. The shell 11 defines a accommodating chamber 111; adjacent acoustic liner units 1 can be connected through their respective shells 11; one end of the accommodating chamber 111 in the length direction is an open end 1111 for sound waves to enter, and the other end is a closed end 1112, so that the sound waves are processed inside the acoustic liner unit 1. The acoustic liner element 12 is arranged in the accommodating chamber 111, and the acoustic liner element 12 defines a first chamber 121. The first chamber 121 is provided with a first orifice plate structure 1211 and a second orifice plate structure 1212 at both ends in the length direction, respectively. The first orifice plate structure 1211 is located on one side of the open end 1111 of the accommodating chamber 111, and the second orifice plate structure 1212 is located on one side of the closed end 1112 of the accommodating chamber 111. The closed end here refers to a basic closure. For example, as shown in the figure, a hole for a rod to enter can be provided at the closed end, but generally the gap between the rod and the hole is small and can be ignored here.

[0067] refer to Fig. 6A , Figure 6B as well as Fig. 7A , Figure 7B As shown, in the length direction of the accommodating chamber 111 , the acoustic lining element 12 and the housing 11 can be relatively displaced.

[0068] In some embodiments, for the structure in which the acoustic liner element 12 and the shell 11 can be relatively displaced, specifically, the acoustic liner unit 1 provides an acoustic channel including from the first orifice plate structure 1211 through the first chamber 121, the second orifice plate structure 1212 to the closed end 1112 of the accommodating chamber 111. In the length direction of the accommodating chamber 111, the acoustic liner element 12 and the shell 11 can be relatively displaced, and the first orifice plate structure 1211 of the acoustic liner element 12 can be displaced to the outside of the open end 1111 of the shell 11, so that the distance between the second orifice plate 1212 structure and the closed end 1112 of the shell 11 can be variable to change the length of the acoustic channel.

[0069] In some embodiments, the connection between the shells 11 can be a magnetic connection. For example, the shell 11 is provided with a second magnetic member 112, and the adjacent sound liner units 1 can be magnetically connected through the second magnetic member 112 of the respective shells 11. For a hexagonal shell, each surface is provided with a magnetic member. This makes disassembly and maintenance convenient and saves material costs. It has a wide range of applicability through splicing. However, this is not limited to other structures, and it can also be a fixed connection with a mortise and tenon structure, for example.

[0070] As shown in the figure, the cross-sections of the shell 11 and the acoustic lining element 12 are both hexagonal, that is, a columnar hexagonal honeycomb shape. The honeycomb-shaped acoustic lining unit is light in weight, high in strength, high in rigidity, good in stability, and has the advantages of good sound insulation and noise reduction effects. However, this is not a limitation, and other structures may also be used.

[0071] The manufacturing process and materials of the acoustic lining unit can be manufactured by additive manufacturing, using lightweight materials such as resin and paraffin, which is easy to implement. The manufacturing method of the acoustic lining member 10 can be to first manufacture multiple independent acoustic lining units 1, for example, by the above-mentioned additive manufacturing process, and then assemble and connect the multiple acoustic lining units 1 to form the acoustic lining member 10.

[0072] The meaning of acoustic channel is explained here, which refers to the acoustic path along which noise propagates after entering the noise reduction lining.

[0073] Specific comparison can be Fig. 6A , Figure 6B as well as Fig. 7A , Figure 7B ,exist Fig. 6A , Figure 6B In the structure shown, the relative position of the acoustic lining element 12 and the housing 11 in the length direction of the accommodating chamber 111 is located at a first position, which may be an initially set position. Fig. 7A , Figure 7B In the structure shown, the relative position of the acoustic lining element 12 and the housing 11 in the length direction of the accommodating chamber 111 is located at the second position. Fig. 6A , Figure 6B In the structure shown, the length of the acoustic channel is approximately equal to the length x of the acoustic lining element 12 itself. Fig. 7A , Figure 7B In the structure shown, since the acoustic lining element 12 is relatively unique to the housing 11, the length of the acoustic channel is the length x of the acoustic lining element 12 plus the displacement Delt h, that is, Fig. 7A , Figure 7B Zhongyu Fig. 6A , Figure 6B The difference in h0.

[0074] Fig. 6A , Figure 6B In this state, the length of the rod exposed outside the cavity is h0, and the volume of the entire cavity is V0≈S0x, where S0 and x represent the hexagonal cross-sectional area of ​​the acoustic lining element 12 and the length of the acoustic lining element 12 respectively.

[0075] When the acoustic lining element 12 and the housing 11 are relatively displaced in the length direction of the accommodating chamber 111, this state can be Fig. 7A as well as Figure 7BThe second orifice plate structure 1212 allows the noise to be transmitted from the first cavity, i.e., the first cavity 121 of the acoustic liner element, to the second cavity, i.e., the space between the second orifice plate structure 1212 and the closed end 1112. At this time, the length of the rod exposed outside the cavity becomes h0'. Since the length of the acoustic liner element 12 in the accommodating cavity changes to Delt_h = h0-h0', it directly affects the change in its volume, i.e., Delt_V≈Delt_h·S0.

[0076] The mechanism of noise reduction can be simply summarized as the resonance between the sound-absorbing material and the sound wave. As the amplitude of the material increases, the damping heat becomes stronger and the sound absorption capacity becomes stronger, so that the energy of the sound wave is quickly dissipated, achieving the purpose of attracting noise reduction. The following formula gives the resonant frequency expression of the honeycomb sound lining in general:

[0077]

[0078] Where f is the resonance frequency, c is the speed of sound, σ is the perforation rate, h is the cavity depth, L is the cover thickness, and the perforation rate is the ratio of the perforation area to the total area, that is, The perforation rate σ and the cover thickness L can be designed according to the needs. After these two design parameters are fixed, the control variable for controlling the resonance frequency of the cavity is the cavity depth, which is the length of the acoustic channel introduced above. The target frequency can be adjusted by adjusting the length.

[0079] As mentioned above, the beneficial effect of this is that, by allowing the outer shell of the sound lining unit and the sound lining element to be relatively displaced in the length direction, the cavity depth of the resonance cavity that plays a sound-absorbing role can be adjusted according to different working conditions, so that different cavity depths correspond to different working conditions, thereby corresponding to different target noise reduction frequencies. In this way, the same sound lining can achieve targeted noise reduction processing for specific noise frequencies under different working conditions, so that the sound lining can take into account the fundamental frequencies corresponding to various working conditions, thereby improving the noise reduction effect.

[0080] Continue to refer Figure 3 , Figure 4 as well as FIG. 5A to FIG. 7B As shown, in some embodiments, a single acoustic liner unit 1 may further include a base 13, which is located outside one side of the closed end 1112 of the housing 11, and adjacent acoustic liner units 1 may be connected via their respective bases 13. Figure 3 as well as Figure 4 As shown, adjacent acoustic liner units 1 can also be connected through the base 13, that is, the base 13 is provided with a first magnetic member 131, and the adjacent acoustic liner units 1 can be magnetically connected through the first magnetic member 131 of each base 13. The beneficial effect is also easy to assemble and disassemble. However, it is not limited to the order, for example, mortise and tenon structure connection can also be adopted.

[0081] Continue to refer FIG. 5A to FIG. 7B As shown, in some embodiments, the structure for realizing the relative displacement of the acoustic lining element 12 and the shell 11 may be that the base 13 is provided with a driving part 14, the driving part 14 is connected to the acoustic lining element 12, so as to drive the acoustic lining element 12 and the shell 11 to be able to relative displacement, and the driving part 14 includes a driving rod 141, and one end of the driving rod 141 is connected to the second orifice plate structure 1212 of the acoustic lining element 12. Such a structure is simple and easy to implement. In addition, in some embodiments, the acoustic lining unit 1 may further include an elastic member 15, the elastic member 15 is respectively connected to the shell 11 and the acoustic lining element 12, and when the acoustic lining element 12 and the shell 11 are relatively displaced in the length direction of the accommodating chamber 111, the elastic member 15 can provide a buffering effect.

[0082] refer to Figure 8 As shown, the present application also provides a noise reduction method for a power propulsion system, characterized in that, using the sound lining member 10 as described above, the noise reduction method includes: in a first operating condition of the power propulsion system, the relative position of the sound lining element 12 of at least part of the sound lining unit 1 and the outer shell 11 in the length direction of the accommodating chamber 11 is set to a first position; in a second operating condition of the power propulsion system, the relative position of the sound lining element 12 of at least part of the sound lining unit 1 and the outer shell 11 in the length direction of the accommodating chamber 111 is set to a second position.

[0083] It can be understood that, in some embodiments, the acoustic lining unit 1 where the acoustic lining element 12 set to the second position in the second working condition is located is the same as the acoustic lining unit 1 where the acoustic lining element 12 set to the first position in the first working condition is located. That is, in the acoustic lining component 10, for the same acoustic lining unit 1, the relative movement of the acoustic lining element 12 and the outer shell 11 for each working condition can be achieved. However, this is not limited to the above. For example, it can be set that a part of the acoustic lining units in the acoustic lining component 10 specifically corresponds to one or more working conditions for the movement of the acoustic lining element 12 and the outer shell 11 in a certain stroke, while another part of the acoustic lining units specifically corresponds to another one or more working conditions for the movement of the acoustic lining element 12 and the outer shell 11 in another specific stroke. This makes it easier to achieve control in some cases, but it takes up more space.

[0084] like Fig. 9As shown, in some embodiments, the adjustment from the first position to the second position can be achieved through closed-loop control. It is mainly composed of a control plan, a controller, an actuator, a control object (acoustic liner unit), and an LVDT displacement sensor. The control plan is converted according to the airworthiness requirements. It is a set of expected values ​​of the relative displacement between the acoustic liner element and the shell under flight conditions (altitude, Mach number, percentage conversion speed, ambient temperature, etc.). It can be obtained according to the optimization algorithm offline in combination with the acoustic liner structure, which will not be repeated in this patent. The controller can select a robust LPV PID controller, which is essentially a PID controller with variable gain. It can also adjust the PID control parameters Kp, Ki, and Kd in real time according to the working conditions so that the closed-loop control accuracy of the entire displacement meets the requirements. The actuator can generally select an actuator cylinder 20, and its structure is as follows Fig.10 As shown, the input of the actuator can be the magnitude of the electric current, and different output currents correspond to different displacements of the push rod of the actuator. Of course, it is not necessary to use only the actuator here, and a flexible actuator (such as an inflation control) can also be used. The push rod of the actuator is directly connected to the base 13 to ensure that the displacement acts on the control object sound lining element 12. As a closed-loop control, a displacement sensor is also required to feedback the actual displacement h detected to the controller in real time. After that, the controller will control and adjust the difference between the expected value of the displacement and the actual measurement based on the flight conditions. The control actuator adjusts the control object in real time. The control accuracy depends on the control algorithm (control law), etc. This patent does not repeat this part. For a more intuitive description, the process of the engine controller adjusting the displacement in real time according to the flight conditions is given in the form of a flow chart. The logical sequence and content of this process are given. For details, please refer to see Fig.11 The content shown.

[0085] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A sound lining member (10), characterized in that: include: A plurality of sound lining units (1), each sound lining unit (1) comprising: The housing (11) defines a receiving chamber (111); adjacent sound liner units (1) can be connected via their respective housings (11); one end of the receiving chamber (111) in the length direction is an open end (1111) for sound waves to enter, and the other end is a closed end (1112) so that the sound waves are processed inside the sound liner unit (1); A sound lining element (12) is arranged in the accommodating chamber (111), the sound lining element (12) defines a first chamber (121), and the first chamber (121) is provided with a first orifice plate structure (1211) and a second orifice plate structure (1212) at two ends in a length direction, respectively; the first orifice plate structure (1211) is located on one side of an open end (1111) of the accommodating chamber (111), and the second orifice plate structure (1212) is located on one side of a closed end (1112) of the accommodating chamber (111); Wherein, in the length direction of the accommodating chamber (111), the acoustic lining element (12) and the housing (11) are capable of relative displacement.

2. The acoustic lining member (10) according to claim 1, characterized in that: The acoustic lining unit (1) provides an acoustic channel including from the first orifice plate structure (1211) through the first chamber (121), the second orifice plate structure (1212) to the closed end (1112) of the accommodating chamber (111); in the length direction of the accommodating chamber (111), the acoustic lining element (12) and the outer shell (11) are capable of relative displacement; the first orifice plate structure (1211) of the acoustic lining element (12) is capable of displacement to the outside of the open end (1111) of the outer shell (11), so that the distance between the second orifice plate (1212) structure and the closed end (1112) of the outer shell (11) is variable, thereby changing the length of the acoustic channel.

3. The acoustic lining member (10) according to claim 1, characterized in that: The acoustic liner unit (1) further comprises a base (13), wherein the base (13) is located outside one side of the closed end (1112) of the shell (11), and adjacent acoustic liner units (1) can be connected via their respective bases (13).

4. The acoustic lining member (10) according to claim 3, characterized in that: The base (13) is provided with a driving part (14), and the driving part (14) is connected to the acoustic lining element (12) so as to drive the acoustic lining element (12) and the housing (11) to move relative to each other.

5. The acoustic lining member (10) according to claim 4, characterized in that: The driving part (14) comprises a driving rod (141), one end of which is connected to the second orifice plate structure (1212) of the acoustic lining element (12).

6. The acoustic lining member (10) according to claim 3, characterized in that: The base (13) is provided with a first magnetic member (131), and adjacent acoustic liner units (1) can be magnetically connected via the first magnetic members (131) of their respective bases (13).

7. The acoustic lining member (10) according to claim 1, characterized in that: It also includes an elastic member (15), wherein the elastic member (15) is respectively connected to the shell (11) and the acoustic lining element (12), and when the acoustic lining element (12) and the shell (11) are relatively displaced in the length direction of the accommodating chamber (111), the elastic member (15) can provide a buffering effect.

8. The acoustic lining member (10) according to claim 1, characterized in that: The shell (11) is provided with a second magnetic member (112), and adjacent acoustic liner units (1) can be magnetically connected via the second magnetic members (112) of their respective shells (11).

9. The acoustic lining member (10) according to claim 1, characterized in that: The cross-sections of the shell (11) and the acoustic lining element (12) are both hexagonal.

10. A method for manufacturing an acoustic lining member (10), characterized in that: Used to manufacture the acoustic lining member (10) as claimed in any one of claims 1 to 9.

11. The manufacturing method according to claim 10, characterized in that: The manufacturing method comprises: manufacturing the plurality of independent acoustic lining units (1); assembling and connecting the plurality of acoustic lining units (1) to form the acoustic lining member (10).

12. A power propulsion system, characterized in that: It comprises the acoustic lining member (10) as claimed in any one of claims 1 to 9.

13. The propulsion system according to claim 12, characterized in that: The power propulsion system is a gas turbine engine, and the acoustic lining component (10) is arranged in the nacelle of the gas turbine engine.

14. A noise reduction method for a power propulsion system, characterized in that: Using the acoustic lining member (10) according to any one of claims 1 to 9, the noise reduction method comprises: In a first operating condition of the power propulsion system, the relative position of at least part of the acoustic lining element (12) of the acoustic lining unit (1) and the outer shell (11) in the length direction of the accommodating chamber (111) is set to a first position; In the second operating condition of the power propulsion system, the relative position of the acoustic lining element (12) of at least part of the acoustic lining unit (1) and the outer shell (11) in the length direction of the accommodating chamber (111) is set to a second position.

15. The noise reduction method according to claim 14, characterized in that: The acoustic lining unit (1) where the acoustic lining element (12) is set to the second position in the second working condition is located, and the acoustic lining unit (1) where the acoustic lining element (12) is set to the first position in the first working condition is the same acoustic lining unit.

16. An acoustic lining unit (1), used for an acoustic lining member (10), characterized in that: The sound lining unit (1) comprises: The housing (11) defines a receiving chamber (111); adjacent sound liner units (1) can be connected via their respective housings (11); one end of the receiving chamber (111) in the length direction is an open end (1111) for sound waves to enter, and the other end is a closed end (1112) so that the sound waves are processed inside the sound liner unit (1); A sound lining element (12) is arranged in the accommodating chamber (111), the sound lining element (12) defines a first chamber (121), and the first chamber (121) is provided with a first orifice plate structure (1211) and a second orifice plate structure (1212) at two ends in a length direction, respectively; the first orifice plate structure (1211) is located on one side of an open end (1111) of the accommodating chamber (111), and the second orifice plate structure (1212) is located on one side of a closed end (1112) of the accommodating chamber (111), Wherein, in the length direction of the accommodating chamber (111), the acoustic lining element (12) and the housing (11) are capable of relative displacement.

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