A method of radiation sound field enhancement and interference reduction for a gas turbine

Abstract

A method for enhancing and reducing interference of a radiation sound field of a gas turbine is disclosed, in which a low-high pressure rotor of a gas turbine test bench is taken as a research object to simulate structural noise of the gas turbine; a sound pressure sensor is arranged to form a plane measurement surface to measure holographic sound pressure data; an equivalent wave model is solved based on the holographic sound pressure data and a sound source structure; a wave function radiation position is obtained according to position coordinates of a to-be-interpolated point; a statistical optimal near-field acoustic holography is used to expand a wave function matrix of an interpolation surface element to obtain a transfer matrix containing measurement points and interpolation points; interpolation data is obtained by in-situ reconstruction of a sound field by using the holographic sound pressure data and the transfer matrix, so that sound field data enhancement is realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of mechanical structure sound radiation signal processing, in particular to a gas turbine radiation sound field enhancement and interference reduction method. BACKGROUND

[0002] The gas turbine is an important power device, and its vibration exceeds the standard during operation, which affects the operation reliability and safety of the gas turbine, and its structural noise also directly affects the normal life of the workers and surrounding residents due to slow attenuation and long radiation distance. Therefore, the vibration reduction and noise reduction of the gas turbine are of great significance to improve its service life and improve the surrounding working environment, and the premise of accurately controlling the noise of the gas turbine is to obtain its effective radiation sound field.

[0003] Statistically Optimized Near-field Acoustic Holography (SONAH) is a very effective noise source identification, positioning and sound field visualization method, which obtains enough low spatial frequency propagation wave and high spatial frequency evanescent wave components near the noise source through near-field testing, and reconstructs the sound pressure on the surface of the sound source or predicts the sound pressure at each place in the entire three-dimensional sound field by using a spatial transformation algorithm.

[0004] Using SONAH to reconstruct or predict the three-dimensional sound field needs to test the two-dimensional sound field near the noise source. However, the volume of the gas turbine is huge, which leads to the need for a large number of microphones and matching parallel channels for sound field testing. Too few microphones cannot test enough information, which leads to the inability to perform subsequent sound field visualization. Too many microphones will sharply increase the cost, and the number of channels of the data acquisition instrument also limits the use of too many microphones.

[0005] Therefore, how to recover enough measurement point information under the condition of a small number of sensors, and use the recovered two-dimensional sound pressure to reconstruct or predict the entire three-dimensional sound field can reduce the sound field reconstruction error and improve the resolution of the spatial sound field.

[0006] The above information disclosed in the background section is only used to enhance the understanding of the background of the present application, and therefore can contain information that is not prior art known to those of ordinary skill in the art. SUMMARY

[0007] In view of the problems in the prior art, the present application proposes a gas turbine radiation sound field enhancement and interference reduction method, which recovers enough measurement point information under the condition of a small number of sensors, and uses the recovered two-dimensional sound pressure to reconstruct or predict the entire three-dimensional sound field, which can reduce the sound field reconstruction error and improve the resolution of the spatial sound field, and realizes sound field data enhancement.

[0008] The application aims at realizing the technical scheme, a gas turbine radiation sound field enhancement and interference reduction method comprises,

[0009] Step 1, using the low high-pressure rotor of the gas turbine experiment table as the research object to simulate the gas turbine structure noise;

[0010] Step 2, arranging the sound pressure sensor to constitute a plane measurement surface to measure the holographic sound pressure data;

[0011] Step 3, solving the equivalent wave model based on the holographic sound pressure data and the sound source structure;

[0012] Step 4, based on the equivalent wave model, obtaining the wave function radiation position according to the position coordinates of the to-be-interpolated point, using the statistical optimal near-field acoustic holography to expand the wave function matrix of the interpolation surface element, and obtaining the transfer matrix containing the measurement points and the interpolation points;

[0013] Step 5, using the holographic sound pressure data and the transfer matrix to perform in-situ reconstruction of the sound field to obtain the interpolation data.

[0014] In the gas turbine radiation sound field enhancement and interference reduction method, the low high-pressure rotor is a column.

[0015] In the gas turbine radiation sound field enhancement and interference reduction method, the column has an axial length of 0.8 m and a radius of 0.35 m.

[0016] In the gas turbine radiation sound field enhancement and interference reduction method, the interpolation surface element wave function matrix expansion comprises,

[0017] The space contains L coherent sources which are relatively independent in structure, L wave function sets are selected, and the value of each element wave function at the M measurement points on the holographic surface is expressed as a holographic surface element wave function matrix in the form of a matrix:

[0018]

[0019] In the formula, Ф(k j , r H ) is the j-order element wave function, k j is the sampling point, j=1, 2,..., N, r H represents the spatial position of the holographic surface, r HM represents the grid point position on the holographic surface, and the superscript l represents the lth structural sound source, l=1, 2,..., L.

[0020] The interpolation of holographic data requires that the reconstruction plane is also set at the same position as the holographic plane. Generally, there are only M = m x n reconstruction points on the reconstruction plane. To keep the area of the reconstruction plane unchanged, the m x n grid points are equally divided into Q = (2m-1) x (2n-1) grid points, and the wave function radiation position is obtained.

[0021] The unit wave function matrix of the reconstruction plane (i.e. the interpolation plane) and the unit wave function matrix of the holographic plane are of the same form, only r H is replaced by r S . For double interpolation of data, Q = (2m-1) x (2n-1) interpolation grid points are substituted into the unit wave function matrix of the reconstruction plane to obtain the expanded unit wave function matrix of the interpolation plane:

[0022]

[0023] In the formula, r S represents the spatial position of the interpolation plane, r SQ represents the grid point position on the interpolation plane.

[0024] L unit wave function vectors are combined in order to obtain a matrix, and the transfer matrix of the wave function set is obtained. The formula can be written in the following form respectively

[0025] A(r H ) = [A 1 (r H ), A 2 (r H ), …, A L (r H )] T (3)

[0026] α(r S ) = [α 1 (r S ), α 2 (r S ), …, α L (r S )] T (4)

[0027] In the formula, A(r H ) is the combined unit wave function matrix of the holographic plane, and α(r S ) is the expanded unit wave function matrix of the interpolation plane.

[0028] The gas turbine radiation sound field enhancement and interference reduction method uses the holographic sound pressure data and the transfer matrix to perform in-situ reconstruction of the sound field to obtain interpolation plane data:

[0029]

[0030] where p H is the holographic sound pressure data, the superscript T denotes matrix transposition, the superscript + denotes the generalized inverse of a matrix, C(r S ) is an extended transfer matrix.

[0031] Compared with the prior art, the gas turbine radiation sound field enhancement and interference reduction method has the following advantages: the gas turbine radiation sound field enhancement and interference reduction method is suitable for interpolating gas turbine structural noise sound field data with slow attenuation and long radiation distance, sufficient information of measuring points can be recovered under the condition of a small number of sensor tests, the entire three-dimensional sound field can be reconstructed or predicted by using the recovered two-dimensional sound pressure, the sound field reconstruction error can be reduced, and the resolution of the spatial sound field can be improved. The statistical optimal near-field sound holography is used to interpolate point data, the window effect and winding error caused by the prior method are overcome, and the large-volume gas turbine sound field test can be realized by using a small-area test array and step-by-step multiple tests. The equivalent wave model is used to fit the actual gas turbine noise source distribution, the complex operation of setting a large number of equivalent sources in the equivalent source method of the prior art is improved, the sound field propagation model is more in line with the actual gas turbine structural noise radiation rule, and then the interpolated sound field information is closer to the real sound field information. The gas turbine structural noise sound field is interpolated, sufficient information of measuring points can be recovered under the condition of a small number of sensor tests, the entire three-dimensional sound field can be reconstructed or predicted by using the recovered two-dimensional sound pressure, the sound field reconstruction error can be reduced, the resolution of the spatial sound field can be improved, the sound field data can be enhanced, and the function of automatically reducing interference is also provided, which is helpful for locating the internal noise source of the gas turbine and obtaining the spatial radiation sound field of the gas turbine. BRIEF DESCRIPTION OF DRAWINGS

[0032] Various other advantages and benefits of the present application will become apparent to those of ordinary skill in the art, upon reading the following detailed description of the preferred embodiment. The accompanying drawings are intended to only illustrate preferred embodiments of the application, and are not intended to limit the application thereto. Obviously, other drawings than those shown below can be derived from the drawings shown below without paying any creative effort, and the drawings shown below are only some embodiments of the present application. Moreover, the same reference numerals are used to denote the same components throughout the drawings.

[0033] In the drawings:

[0034] Figure 1 is a theoretical sound pressure graph of a low-pressure rotor holographic measurement surface of a gas turbine radiation sound field enhancement and interference reduction method according to one embodiment of the present application (f = 100 Hz);

[0035] Figure 2This is a low-pressure rotor holographic measurement surface extracted sound pressure map (f = 100Hz) of a gas turbine radiated sound field enhancement and interference reduction method according to an embodiment of the present invention;

[0036] Figure 3 This is a low-pressure rotor holographic measurement surface interpolated sound pressure map (f = 100Hz) of a gas turbine radiated sound field enhancement and interference reduction method according to an embodiment of the present invention;

[0037] Figure 4 This is a theoretical sound pressure map (f = 115 Hz) of a high-pressure rotor holographic measurement surface of a gas turbine radiated sound field enhancement and interference reduction method according to an embodiment of the present invention.

[0038] Figure 5 This is a high-pressure rotor holographic measurement surface extracted sound pressure map (f = 115Hz) of a gas turbine radiated sound field enhancement and interference reduction method according to an embodiment of the present invention;

[0039] Figure 6 This is an interpolated sound pressure map (f = 115 Hz) of the high-pressure rotor holographic measurement surface of a gas turbine radiated sound field enhancement and interference reduction method according to an embodiment of the present invention.

[0040] The present invention will be further explained below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0041] The following will refer to the appendix. Figures 1 to 6 Specific embodiments of the invention will be described in more detail below. While specific embodiments of the invention are shown in the accompanying drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0042] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions are preferred embodiments for carrying out the invention; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of the invention. The scope of protection of this invention is determined by the appended claims.

[0043] In order to facilitate the understanding of the embodiments of the present application, specific embodiments will be further explained and described below with reference to the accompanying drawings, and each drawing does not constitute a limitation on the embodiments of the present application.

[0044] In order to better understand, as Figures 1 to 6 shown, the gas turbine radiation sound field enhancement and interference reduction method comprises:

[0045] Step 1, using the low high pressure rotor of the gas turbine test bench as the research object to simulate the gas turbine structural noise;

[0046] Step 2, arranging the sound pressure sensor to constitute a plane measurement surface to measure the holographic sound pressure data;

[0047] Step 3, solving the equivalent wave model based on the holographic sound pressure data and the sound source structure;

[0048] Step 4, based on the equivalent wave model, obtaining the wave function radiation position according to the position coordinates of the to-be-interpolated point, expanding the wave function matrix of the interpolation surface element by using the statistical optimal near-field acoustic holography, and obtaining the transfer matrix containing the measurement points and the interpolation points at the same time;

[0049] Step 5, using the holographic sound pressure data and the transfer matrix to reconstruct the sound field in situ to obtain the interpolation data.

[0050] The present application sets up an equivalent wave model and expands the wave function, combines the statistical optimal near-field acoustic holography algorithm, calculates the complex sound pressure values of more space positions, improves the complex operation of setting a large number of equivalent sources in the traditional equivalent source method, and makes the sound field propagation model more consistent with the actual gas turbine structural noise radiation rule, so that the interpolated sound field information is closer to the real sound field information, and the function of reducing noise interference is also achieved. It has the characteristics of less microphone number, low measurement cost, high sound field interpolation precision, automatic noise reduction and the like. The method provided by the present application can restore enough measurement point information under the condition of a small number of sensors, reconstruct or predict the entire three-dimensional sound field by using the restored two-dimensional sound pressure, can reduce the sound field reconstruction error, improve the spatial sound field resolution, realize sound field data enhancement, and is helpful for positioning the internal noise source of the gas turbine and obtaining the spatial radiation sound field of the gas turbine.

[0051] In the preferred embodiment of the gas turbine radiation sound field enhancement and interference reduction method, the low high pressure rotor is a column.

[0052] In the preferred embodiment of the gas turbine radiation sound field enhancement and interference reduction method, the axial length of the column is 0.8m, and the radius is 0.35m.

[0053] In the preferred embodiment of the gas turbine radiation sound field enhancement and interference reduction method, the interpolation surface element wave function matrix expansion includes,

[0054] There are L coherent sources in the space, and L sets of wave functions are selected. The value of each unit wave function at M = m x n measuring points on the holographic surface is expressed in matrix form as (unit wave function matrix of the holographic surface):

[0055]

[0056] In the formula, Φ(k j , r H ) is a unit wave function of j order, k j is a sampling point, j = 1, 2,..., N, r H represents the spatial position of the holographic surface, r HM represents the grid point position on the holographic surface, the superscript indicates the lth structural sound source, and l = 1, 2,..., L.

[0057] Interpolation of the holographic data requires that the reconstruction surface also be set at the same position as the holographic surface. In general, there are only M = m x n reconstruction points on the reconstruction surface. To keep the area of the reconstruction surface unchanged, the m x n grid points are equally divided into Q = (2m-1) x (2n-1) grid points, and the wave function radiation position is obtained.

[0058] The unit wave function matrix of the reconstruction surface (i.e., the interpolation surface) is the same as that of the holographic surface, and r H is replaced by r S . For double interpolation data, Q = (2m-1) x (2n-1) interpolation grid points are substituted into the unit wave function matrix of the reconstruction surface to obtain the expanded interpolation surface unit wave function matrix:

[0059]

[0060] In the formula, r S represents the spatial position of the interpolation surface, and r SQ represents the grid point position on the interpolation surface.

[0061] L unit wave function vectors are combined in order to form a matrix, and the transfer matrix of the set of wave functions is obtained. The formula can be written in the following form, respectively

[0062] A(r H ) = [A 1 (r H ), A 2 (r H ),..., A L (r H )] T (3)

[0063] α(r S ) = [α1 (r S ), α 2 (r S ), …, α L (r S )] T (4)

[0064] wherein A(r H ) is the combined holographic surface element wave function matrix, and α(r S ) is the combined interpolation surface extended element wave function matrix.

[0065] The gas turbine radiation sound field enhancement and interference reduction method uses the holographic sound pressure data and the transfer matrix to obtain interpolation surface data by in-situ reconstruction of the sound field:

[0066]

[0067] wherein p H is the holographic sound pressure data, the superscript T represents matrix transposition, the superscript + represents the generalized inverse of the matrix, C(r S ) is the extended transfer matrix.

[0068] In one embodiment, the method comprises the following steps:

[0069] Step 1, for simulating the structural noise of a gas turbine, a low-high pressure rotor part (cylindrical) of a gas turbine test bench with an axial length of 0.8 m and a radius of 0.35 m is taken as the research object;

[0070] Step 2, a plane measurement surface composed of microphones is used, reasonable measurement parameters are selected, sound pressure sensors are arranged, and efficient holographic sound pressure data are obtained;

[0071] Step 3, according to the holographic sound pressure data tested in Step 2, an equivalent wave model is solved in combination with the actual sound source structure;

[0072] Step 4, according to the position coordinates of the required interpolation points, the wave function radiation position is set, the interpolation surface element wave matrix is extended, and a transfer matrix containing the measurement points and the interpolation points is obtained;

[0073] Step 5, the holographic sound pressure data tested in Step 2 and the interpolation point transfer matrix in Step 4 are used to perform in-situ reconstruction of the sound field, and interpolation data are obtained. The interpolation process is as follows:

[0074] The core idea of the holographic surface sound pressure interpolation technique based on the equivalent source method is that the radiation superposition of orthogonal spherical wave sources of different orders can restore any sound field distribution, and the sound field reconstruction can be completed as long as the parameters of the orthogonal spherical wave sources are determined. This idea is applied to the SONAH algorithm to propose an interpolation method based on the SONAH algorithm. Once the equivalent wave model of the given field is determined, the sound pressure value at any point in space can be calculated. Since the equivalent wave model (EWM) of all given fields can be formulated as a combination of plane, cylindrical, spherical or other basic wave functions, the sound pressure information of the reconstruction surface can be calculated by using the equivalent wave model to determine the corresponding transfer matrix and combining the measured data. Using a limited subset of functions to provide an approximation of the sound field, using the equivalent wave model of different basic wave function combinations can reduce the need for high-order functions, reduce the number of measurements, and reduce errors. Thus, when calculating the spatial sound field generated by the actual sound source, the specific form of the actual sound source can be ignored, and the spatial sound field generated by the equivalent wave model equivalent to it can be directly calculated.

[0075] The space contains L structurally independent coherent sources, and L wave function sets are selected. The value of each unit wave function at M = m x n measurement points on the holographic surface is represented in matrix form as (holographic surface unit wave function matrix):

[0076]

[0077] In the formula, Ф(k j , r H ) is a j-order unit wave function, k j is a sampling point, j = 1, 2,..., N, r H represents the spatial position of the holographic surface, r HM represents the grid point position on the holographic surface, and the superscript l represents the lth structural sound source, l = 1, 2,..., L.

[0078] Interpolation of holographic data requires that the reconstruction surface also be placed at the same position as the holographic surface. In general, there are only M = m x n reconstruction points on the reconstruction surface, and the m x n grid points are equally spaced into Q = (2m-1) x (2n-1) grid points, obtaining the wave function radiation position.

[0079] The unit wave function matrix of the reconstruction surface (i.e., the interpolation surface) is the same as the unit wave function matrix of the holographic surface, and r H is replaced by r S . For double interpolation data, Q = (2m-1) x (2n-1) interpolation grid points are substituted into the unit wave function matrix of the reconstruction surface to obtain the expanded interpolation surface unit wave function matrix:

[0080]

[0081] wherein r S represents the interpolation surface spatial position, r SQ represents the grid point position on the interpolation surface;

[0082] L unit wave function vectors are combined in order to form a matrix, and a transfer matrix of the wave function set is obtained, which can be respectively simplified as the following forms

[0083] A(r H )=[A 1 (r H ),A 2 (r H ),…,A L (r H )] T (3)

[0084] α(r S )=[α 1 (r S ),α 2 (r S ),…,α L (r S )] T (4)

[0085] wherein A(r H ) is the combined holographic surface unit wave function matrix, and α(r S ) is the combined interpolation surface extended unit wave function matrix.

[0086] The gas turbine radiation sound field enhancement and interference reduction method uses the holographic sound pressure data and the transfer matrix to obtain interpolation surface data by in-situ reconstruction of the sound field:

[0087]

[0088] wherein p H is the holographic sound pressure data, the superscript T represents the matrix transpose, the superscript + represents the generalized inverse of the matrix, and C(r S ) is the extended transfer matrix.

[0089] To verify the effectiveness of the statistical optimal near-field sound holography-based gas turbine sound field data enhancement and interference reduction method for cylindrical and columnar gas turbine sound field interpolation, a shell structure with an axial length of 0.8 m and a diameter of 0.35 m is simulated. The coupled low-pressure rotor and high-pressure rotor are set inside the experimental table, and the rotational speeds are set to 6000 rpm and 6900 rpm, respectively.

[0090] Simultaneously, the high and low pressure rotors are turned on, and a 5×7 array (7 along the experimental stage axis) with a microphone spacing of 0.05m is used to scan and measure sound pressure data at a position 0.2m directly above the low pressure rotor and the high pressure rotor (holographic position), respectively, to obtain test data with 10×14 measuring points and an interval of 0.05m.

[0091] The holographic surface test results cover 9×13 data points covering either the low-pressure rotor or the high-pressure rotor. The complex acoustic pressure at each measurement point on the low-pressure rotor is obtained using the cross-spectral method. Figure 1 As shown, the complex acoustic pressure at each measuring point of the high-pressure rotor is as follows: Figure 4 As shown. Rows 1, 3, 5, 7, and 9, and columns 1, 3, 5, 7, 9, 11, and 13 of the low- and high-pressure rotor complex sound pressure matrix are extracted respectively to form a 5x7 matrix, resulting in the following... Figure 2 and Figure 5 The extracted sound pressure level is shown. According to... Figure 2 and Figure 5 Based on the holographic sound pressure distribution and the mechanism that the actual noise is mainly emitted by the vibration of the bearings connected to the rotor, it can be concluded that the equivalent wave model of the high and low pressure rotors is composed of two spherical sources with different volumes. The equivalent wave model is set in this way and the interpolation surface element wave function matrix is ​​obtained. Then the reconstruction surface position is set to 0.2m (the same as the holographic surface position). Finally, the sound field in-situ reconstruction is completed using equation (5). Figure 2 and Figure 5 The 5×7 data points were interpolated and extended to 9×13 data points, resulting in the following: Figure 3 and Figure 6 The interpolated sound pressure diagram of the low-pressure rotor is shown. Figure 3 and Figure 1 In comparison, the interpolation error was 4.92%. Figure 6 and Figure 4 In comparison, the interpolation error was 5.51%. It can be concluded that the sound pressure map interpolated using the method of this invention is basically consistent with the theoretical sound pressure map. At the same time, this method has an automatic noise reduction effect. Compared with the measured theoretical sound pressure map, the interpolated sound pressure map can more clearly and more easily locate the internal noise source. The internal noise source located is consistent with the noise source of the actual experimental platform.

[0092] The enormous size of gas turbines necessitates a large number of microphones and matching parallel channels for acoustic field testing. Insufficient microphones cannot capture enough information, hindering subsequent acoustic field visualization. This invention provides a method for interpolating the acoustic field of gas turbine structural noise. This method can recover sufficient measurement point information with a limited number of sensors. The recovered two-dimensional sound pressure can be used to reconstruct or predict the entire three-dimensional acoustic field, reducing acoustic field reconstruction errors and improving spatial acoustic field resolution. This enhances acoustic field data and helps locate internal noise sources within the gas turbine and acquire its spatial radiated acoustic field, possessing significant theoretical and engineering application value.

[0093] Although the embodiments of the present application have been described above with reference to the accompanying drawings, the present application is not limited to the above-described specific embodiments and areas of application, and the above-described specific embodiments are merely illustrative and instructive, but are not restrictive. Many modifications can be made by those skilled in the art under the teachings of the present specification and without departing from the scope of the present application as defined by the claims.

Claims

1. A method of gas turbine radiation sound field enhancement and interference reduction, characterized by, It comprises, Step 1, using the low high-pressure rotor of the gas turbine test bench as the research object to simulate the structure noise of the gas turbine; Step 2, arranging the sound pressure sensor to constitute a plane measurement surface to measure the holographic sound pressure data; Step 3, solving the equivalent wave model based on the holographic sound pressure data and the sound source structure; Step 4, based on the equivalent wave model, obtaining the wave function radiation position according to the position coordinates of the to-be-interpolated point, expanding the wave function matrix of the interpolation surface element by using the statistical optimal near-field acoustic holography, and obtaining the transfer matrix containing the measurement points and the interpolation points at the same time; Step 5, using the holographic sound pressure data and the transfer matrix to perform in-situ reconstruction of the sound field to obtain the interpolation data; Wherein, the interpolation surface element wave function matrix expansion includes, There are L coherent sources in the space, and L wave function sets are selected, and the value of each unit wave function at M measurement points on the holographic surface is expressed as a holographic surface unit wave function matrix in the form of a matrix: (1) wherein is a j-th order unit wave function, is a sampling point, j = 1, 2, …, N, denotes a spatial position of the holographic surface, denotes a grid point position on the holographic surface, the superscript l denotes the l-th structural sound source, l = 1, 2, …, L; The interpolation of the holographic data needs to set the reconstruction surface at the same position as the holographic surface, and there are only M=m x n reconstruction points on the reconstruction surface, the area of the reconstruction surface is kept unchanged, the m x n grid points are equally divided into Q=(2m-1) x(2n-1) grid points, and the wave function radiation position is obtained, The unit wave function matrix of the reconstruction surface, i.e. the interpolation surface, and the unit wave function matrix of the holographic surface are in the same form, only is replaced by , and the data is interpolated twice. Q= (2m-1) × (2n-1) interpolation grid points are substituted into the unit wave function matrix of the reconstruction surface to obtain the expanded unit wave function matrix of the interpolation surface: (2) wherein represents the interpolated surface space position, represents the interpolated surface grid point position; L unit wave function vectors are combined into a matrix in order to obtain the transfer matrix of the wave function set, which can be respectively simplified in the form of formula: (3) (4) wherein is the combined holographic facet elemental wave function matrix, is the combined interpolated facet extended elemental wave function matrix.

2. The gas turbine engine radiated sound field enhancement and interference reduction method of claim 1, wherein, The low high-pressure rotor is a cylinder.

3. The gas turbine engine radiated sound field enhancement and interference reduction method of claim 2, wherein, The axial length of the cylinder is 0.8m, and the radius is 0.35m.

4. The gas turbine engine radiated sound field enhancement and interference reduction method of claim 1, wherein, The interpolation surface data is obtained by using the holographic sound pressure data and the transfer matrix to perform in-situ reconstruction of the sound field: (5) where is the holographic sound pressure data, the superscript denotes the matrix transpose, the superscript denotes the generalized inverse of a matrix, is the extended transfer matrix.

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