An active control method for underwater vehicle propeller noise

Abstract

A method for actively controlling the propeller noise of an underwater vehicle relates to the field of underwater vehicle noise reduction. The method for actively controlling the propeller noise of an underwater vehicle comprises the following steps: analyzing the sound field of the propeller noise source of the underwater vehicle to determine the frequency range to be controlled; determining the specifications and dimensions of the transducer according to the frequency range to be controlled; setting the propeller position of the propeller of the underwater vehicle as the origin, and determining the placement position and number of the transducer and the hydroacoustic signal sensor through simulation optimization according to the structural characteristics of the stern of the underwater vehicle and the size of the selected transducer; arranging the transducer and the hydroacoustic signal sensor at the stern of the underwater vehicle according to the determined number and position, and detecting the far-field sound source control effect of the underwater vehicle to determine the active noise control effect. The method for actively controlling the propeller noise of the underwater vehicle can effectively control the low-frequency line spectrum noise of the propeller of the underwater vehicle.

Description

Technical Field

[0001] The present application relates to the field of underwater vehicle noise reduction, and in particular, to a method for active control of underwater vehicle propeller noise. Background Art

[0002] At present, the main methods for underwater vehicles to control underwater noise are: reducing drag and noise, using low-noise equipment or reducing noise sources, using isolation means such as vibration isolation devices and rafts to reduce the transmission of vibration to the hull, using equipment sound insulation covers to isolate air noise, and using pipeline silencers and flexible pipes to reduce pipeline noise. These passive noise reduction methods have achieved significant results in reducing high-frequency noise. The above-mentioned passive control technology can also achieve good control effects on medium and high-frequency noise, but the passive control means are not obvious for low-frequency line spectrum noise.

[0003] Currently, active control technology is beginning to be applied to deal with the low-frequency line spectrum noise of underwater vehicles. In fact, the secondary sound source sends vibration or sound signals to interfere with the primary sound source to offset it. For example, active noise reduction equipment such as intelligent shock absorbers and active and passive airbag vibration isolation devices are used to control the low-frequency line spectrum of equipment vibration. However, in some cases, due to the particularity of the noise source, the internal active control means cannot achieve the ideal noise reduction effect, such as the noise generated by the operation of external components such as propellers that are in contact with seawater.

[0004] Therefore, a method is needed to actively control and reduce the noise of the low-frequency line spectrum generated outside the underwater vehicle cabin. Summary of the invention

[0005] The purpose of the present application is to provide a method for actively controlling the noise of an underwater vehicle propeller, which can effectively control the low-frequency line spectrum noise of the underwater vehicle propeller.

[0006] The embodiment of the present application is implemented as follows:

[0007] The present application provides a method for actively controlling the noise of an underwater vehicle propeller, which comprises the following steps:

[0008] Analyze the sound field of the propeller noise source of the underwater vehicle and determine the frequency range of active noise control based on the measured or calculated values ​​of the noise source sound field;

[0009] Determine the specifications and dimensions of the transducer according to the frequency range of active noise control;

[0010] The propeller position of the underwater vehicle's thruster is set as the origin, and the placement position and number of the transducers are determined according to the structural characteristics of the stern of the underwater vehicle and the size of the selected transducers, and the placement position and number of the hydroacoustic signal sensors are determined;

[0011] The transducers and hydroacoustic signal sensors are arranged at the stern of the underwater vehicle in a determined number and position, and the far-field sound source control effect of the underwater vehicle is detected to determine the active noise control effect.

[0012] In some optional implementation schemes, after determining the placement position of the transducer, optimizing the placement position of the transducer includes the following steps:

[0013] Through simulation, the sound pressures P0 and P1 at the position error point and the sound pressure information [p0] and [p1] on the far-field spherical surface are obtained when the propeller and the transducer work separately.

[0014] From the sound pressures P0 and P1 at the position error point, the coefficient α is obtained so that the sound pressure value at the position error point when the propeller and the transducer are working at the same time is P=P0+(α×P1)=0;

[0015] The far-field sound pressure is linearly superimposed using the calculated coefficient α to obtain the sound pressure at the far-field spherical surface in the interference sound field [p] = [p0] + (α × [p1]);

[0016] The value of the total radiated sound power change dW is calculated from the obtained sound pressure data, and the dW of the position error point at different locations is analyzed. The position of the position error point corresponding to the minimum dW is the optimal transducer placement position.

[0017] In some optional implementations, detecting the far-field sound source control effect of the underwater vehicle includes the following steps:

[0018] A point in the near field is selected as a test error point, and the sound field and sound pressure time domain signals in the near field are read as test error signals. The test error signals are band-pass filtered from 20 Hz to 100 Hz and low-frequency signals are retained.

[0019] The adaptive LMS algorithm is used to calculate the transmission signal form of the transducer using the acoustic field and sound pressure time domain signals in the near field;

[0020] Combined with the positional relationship between the transducer and each point in the far field, the far-field sound pressure generated by the transducer is calculated according to the attenuation law of spherical waves;

[0021] The calculation results of the propeller dynamic model are interfered with the far-field sound pressure generated by the transducer to obtain the total sound pressure of the far-field measurement point after control;

[0022] Compare the far-field sound pressure levels before and after using the transducer, and analyze the control effects in different situations.

[0023] In some optional embodiments, at least two transducers are symmetrically arranged in the tail tip tank of the underwater vehicle.

[0024] In some optional embodiments, at least one hydroacoustic signal sensor is arranged directly above the propeller or in a YOZ plane with the propeller position as the origin.

[0025] In some optional embodiments, at least one hydroacoustic signal sensor is arranged in an axial plane of the propeller.

[0026] In some optional embodiments, the aft peak tank, the stern ballast water tank or the trim water tank of the underwater vehicle is provided with at least one transducer.

[0027] The beneficial effects of the present application are as follows: the method for active control of underwater vehicle propeller noise provided by the present application comprises the following steps: analyzing the sound field of the propeller noise source of the underwater vehicle, determining the frequency range of active noise control according to the measured value or calculated value of the noise source sound field; determining the specifications and dimensions of the transducer according to the frequency range of active noise control; setting the propeller position of the underwater vehicle propeller as the origin, determining the placement position and number of the transducer according to the structural characteristics of the stern of the underwater vehicle and the size of the selected transducer, and determining the placement position and number of the hydroacoustic signal sensor; arranging the transducer and the hydroacoustic signal sensor at the stern of the underwater vehicle according to the determined number and position, and detecting the far-field sound source control effect of the underwater vehicle to judge the active noise control effect. The method for active control of underwater vehicle propeller noise provided by the present application can effectively control the low-frequency line spectrum noise of the propeller of the underwater vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of the structure in which a transducer and a hydroacoustic signal sensor are installed on an underwater vehicle in the method for active control of propeller noise of an underwater vehicle provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the simulation of the radiated sound field of the propeller of the underwater vehicle in the method for active control of the underwater vehicle propeller noise provided in an embodiment of the present application;

[0031] Figure 3 A schematic diagram of the radiated sound field simulation of the transducer in the method for active control of underwater vehicle propeller noise provided in an embodiment of the present application;

[0032] Figure 4A schematic diagram of the interference sound field after the initial sound field of the propeller calculated in the active control method for underwater vehicle propeller noise provided in an embodiment of the present application and the sound field applied by the transducer are superimposed;

[0033] Figure 5 A schematic diagram of the change in sound pressure level of the far-field sound field after active control is applied in the method for active control of underwater vehicle thruster noise provided in an embodiment of the present application.

[0034] In the figure: 100, underwater vehicle; 110, propeller; 200, transducer; 210, hydroacoustic signal sensor. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0039] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0040] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0042] The features and performance of the underwater vehicle propeller noise active control method of the present application are further described in detail below in conjunction with the embodiments.

[0043] The present application provides a method for actively controlling the noise of an underwater vehicle propeller, which comprises the following steps:

[0044] S1, analyzing the sound field of the propeller noise source of the underwater vehicle 100, and determining the frequency range of active noise control according to the measured value or calculated value of the sound field of the noise source;

[0045] S2. Determine the specification and size of the transducer 200 according to the frequency range of active noise control;

[0046] S3, setting the position of the propeller 110 of the propeller of the underwater vehicle 100 as the origin, determining the placement position and the number of the transducers 200 according to the structural characteristics of the stern of the underwater vehicle 100 and the size of the selected transducers 200, and determining the placement position and the number of the hydroacoustic signal sensors 210; after determining the placement position of the transducers 200, optimizing the placement position of the transducers 200, and optimizing includes the following steps:

[0047] A. Figure 2 and Figure 3 As shown, the sound pressures P0 and P1 at the position error point and the sound pressure information [p0] and [p1] on the far-field spherical surface (300m) are obtained through simulation when the propeller 110 and the transducer 200 work separately;

[0048] B. Figure 4 As shown, the coefficient α is obtained from the sound pressures P0 and P1 at the position error point so that the sound pressure value at the position error point when the propeller 110 and the transducer 200 work simultaneously is P=P0+(α×P1)=0;

[0049] C. Figure 5 As shown, the far-field sound pressure is linearly superimposed using the calculated coefficient α to obtain the sound pressure at the far-field spherical surface in the interference sound field [p] = [p0] + (α × [p1]);

[0050] D. Calculate the value of the total radiated sound power change dW from the obtained sound pressure data, analyze the dW at different positions of the position error point, and the position of the position error point corresponding to the minimum dW is the optimal transducer 200 placement position.

[0051] S4, such as Figure 1 As shown, two transducers 200 simulating dipole sources are symmetrically arranged in the tail tip cabin of the underwater vehicle 100, and a hydrophone is arranged as an acoustic signal sensor 210 in the axial plane of the propeller 110, and the far-field sound source control effect of the underwater vehicle 100 is detected to determine the active noise control effect; the detection of the far-field sound source control effect of the underwater vehicle 100 includes the following steps:

[0052] a. Select a point in the near field as the test error point, read the sound field and sound pressure time domain signals in the near field as the test error signal, perform a 20Hz to 100Hz bandpass filter on the test error signal and retain the low-frequency signal;

[0053] b. Calculating the transmission signal form of the transducer 200 by using the acoustic field and acoustic pressure time domain signals in the near field using an adaptive LMS algorithm;

[0054] c. Calculate the far-field sound pressure generated by the transducer 200 according to the spherical wave attenuation law based on the positional relationship between the transducer 200 and each point in the far field;

[0055] d. Perform interference processing on the calculation results of the propeller dynamic model and the far-field sound pressure generated by the transducer 200 to obtain the total sound pressure of the far-field measurement point after control;

[0056] e. Compare the far-field sound pressure levels before and after using the transducer 200, and analyze the control effects under different conditions.

[0057] The active control method of underwater vehicle propulsion noise provided by the embodiment of the present application uses the non-watertight space at the stern of the underwater vehicle 100 to arrange the dipole source transducer 200 as the secondary sound source of active control, and sets the hydroacoustic signal sensor 210 as the error sensor, and controls the transducer 200 to emit the secondary sound with the opposite phase to the sound field signal of the propeller 110 to offset the original sound field, thereby realizing active control. When the transducer 200 is arranged, the radiation sound field of the propeller 110 itself and the radiation sound field of the secondary sound source under different conditions are calculated, and the sound pressure signal of the hydroacoustic signal sensor 210 is used to analyze the source level and phase information of the secondary sound source, and then the sound pressure level distribution of the sound field after the coupling interference of the radiation noise of the propeller 110 itself and the secondary sound source is calculated, and the square sum of the sound pressure at the finite point position in the far field is selected as the objective function of active control according to the far field noise reduction amount (wherein the far field sound pressure is obtained according to numerical simulation), and the optimal placement position of the secondary sound source and the error sensor is selected, thereby improving the active noise reduction effect.

[0058] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A method for active control of underwater vehicle propeller noise, It is characterized in that It includes the following steps: Analyzing the acoustic field of the propeller noise source of the underwater vehicle, and determining the frequency range of active noise control according to the measured value or calculated value of the acoustic field of the noise source; Determining the specifications and dimensions of the transducer according to the frequency range of the active noise control; The propeller position of the propeller of the underwater vehicle is set as the origin, and the placement position and the number of the transducers are determined according to the structural characteristics of the stern of the underwater vehicle and the size of the selected transducers, and the placement position and the number of the hydroacoustic signal sensors are determined; Arranging transducers and hydroacoustic signal sensors at a determined number and position at the stern of the underwater vehicle, and detecting the far-field sound source control effect of the underwater vehicle to determine the active noise control effect; After determining the placement position of the transducer, optimizing the placement position of the transducer includes the following steps: Through simulation, the sound pressures P0 and P1 at the position error point and the sound pressure information [p0] and [p1] on the far-field spherical surface are obtained when the propeller and the transducer work separately. From the sound pressures P0 and P1 at the position error point, the coefficient α is obtained so that the sound pressure value at the position error point when the propeller and the transducer are working at the same time is P=P0+(α×P1)=0; The far-field sound pressure is linearly superimposed using the calculated coefficient α to obtain the sound pressure at the far-field spherical surface in the interference sound field [p] = [p0] + (α × [p1]); The value of the total radiated sound power change dW is calculated from the obtained sound pressure data, and the dW of the position error point at different locations is analyzed. The position of the position error point corresponding to the minimum dW is the optimal transducer placement position.

2. The method for active control of underwater vehicle propeller noise according to claim 1, It is characterized in that Testing the far-field sound source control effect of the underwater vehicle includes the following steps: A point in the near field is selected as a test error point, and the sound field and sound pressure time domain signals in the near field are read as test error signals. The test error signals are band-pass filtered from 20 Hz to 100 Hz and low-frequency signals are retained. The adaptive LMS algorithm is used to calculate the transmission signal form of the transducer using the acoustic field and sound pressure time domain signals in the near field; Combined with the positional relationship between the transducer and each point in the far field, the far-field sound pressure generated by the transducer is calculated according to the attenuation law of spherical waves; The calculation results of the propeller dynamic model are interfered with the far-field sound pressure generated by the transducer to obtain the total sound pressure of the far-field measurement point after control; Compare the far-field sound pressure levels before and after using the transducer, and analyze the control effects in different situations.

3. The method for active control of underwater vehicle propeller noise according to claim 1, It is characterized in that At least two of the transducers are symmetrically arranged in the tail peak compartment of the underwater vehicle.

4. The method for active control of underwater vehicle propeller noise according to claim 1, It is characterized in that At least one of the hydroacoustic signal sensors is arranged directly above the propeller or in a YOZ plane with the propeller position as the origin.

5. The method for active control of underwater vehicle propeller noise according to claim 1, It is characterized in that At least one of the hydroacoustic signal sensors is arranged in an axial plane of the propeller.

6. The method for active control of underwater vehicle propeller noise according to claim 1, It is characterized in that The aft peak tank, the stern ballast water tank or the trim adjustment water tank of the underwater vehicle is provided with at least one of the transducers.

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