CN112116901A - Method for improving acoustic subjective evaluation index of medium-low pressure gas pressure regulating tank - Google Patents
Method for improving acoustic subjective evaluation index of medium-low pressure gas pressure regulating tank Download PDFInfo
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Abstract
The application relates to a method for improving acoustic subjective evaluation indexes of a medium and low pressure gas pressure regulating tank, relating to the technical field of sound absorption and noise reduction of the medium and low pressure gas pressure regulating tank, and comprising the following steps: s1, acquiring noise data radiated by the gas pressure regulating box; s2, acquiring subjective evaluation indexes of the sound quality of the noise data; s3, optimizing the sound quality of the gas pressure regulating box, analyzing the subjective evaluation index of the noise data of the gas pressure regulating box, grading the noise energy, and optimizing the structure of the gas pressure regulating box according to different noise emission energies after grading so as to improve the sound quality of the gas pressure regulating box. The application has the effect of improving the acoustic subjective evaluation index of the medium and low pressure gas pressure regulating tank with different noise pollution levels.
Description
Technical Field
The application relates to the technical field of sound absorption and noise reduction of medium and low pressure gas pressure regulating boxes, in particular to a method for improving acoustic subjective evaluation indexes of the medium and low pressure gas pressure regulating boxes.
Background
In recent years, with the increasing execution of environmental protection policies, clean energy is more and more widely used in China. The use amount and the popularization rate of natural gas serving as a main force of clean energy also rise year by year, so that the high-speed development of the urban gas industry is brought. The large number of medium-low pressure gas pressure regulating boxes are indispensable parts of each urban gas operation network, and most of the medium-low pressure gas pressure regulating boxes are distributed in noise-sensitive areas such as residential districts, business and residential mixed areas and the like. The areas belong to the type 1 area and the type 2 area according to the acoustic environment function classification, and the noise emission in the areas has strict limit requirements and is particularly easy to be subjected to related complaints, so that the reduction of the noise related complaints becomes one of the problems faced by many urban gas operators.
The prior relevant research mainly focuses on noise problem treatment of urban gas high-pressure regulating station boxes or door stations with more serious noise pollution, and the research on the emission noise of medium-pressure and low-pressure gas pressure regulating boxes is almost limited to the emission total sound pressure level or simple spectrum analysis, but more and more complaint records show that the type of pressure regulating box which is up to the emission standard or partially up to the emission standard (up to the daytime) is also complained by nearby residents and the like.
Through data statistics and special research of the inventor, the acoustic quality parameter of the noise is a key factor of complaint of the noise. Sound quality can be defined as how well an auditory event satisfies various needs of an individual, with influencing factors including physics (sound field), physiology (auditory perception) and psychology (auditory evaluation). The sound quality is actually an evaluation index combining objective evaluation and subjective evaluation, parameters widely applied to describing noise attributes in the sound quality at present comprise loudness, roughness, jitter degree, sharpness and annoyance degree, and an effective mode for reducing the complaint rate not only reduces the total sound pressure level of noise emission, but also improves the subjective evaluation index of the noise more importantly, so that nearby noise receivers can subjectively feel the influence change of the noise.
Disclosure of Invention
In order to improve the acoustic subjective evaluation indexes of the medium and low pressure gas pressure regulating tank with different noise pollution levels, the application provides a method for improving the acoustic subjective evaluation indexes of the medium and low pressure gas pressure regulating tank.
The application provides a method for improving the acoustic subjective evaluation index of a medium-low pressure gas pressure regulating tank, which adopts the following technical scheme:
a method for improving acoustic subjective evaluation indexes of a medium-low pressure fuel gas pressure regulating tank comprises the following steps:
s1, acquiring noise data of the gas pressure regulating box on external radiation, acquiring a noise signal of the gas pressure regulating box in a working state by utilizing manpower, processing the noise signal to obtain a noise sample, and classifying the noise according to a main noise generation source, wherein the main noise generation source is divided into noise generated by a gas pressure regulating pipeline system in the gas pressure regulating box and noise generated by rigid connection among the gas pressure regulating pipeline system, the gas pressure regulating pipeline system and a gas pressure regulating box structure and a pressure regulating pipeline in the gas pressure regulating box;
s2, acquiring subjective evaluation indexes of the sound quality of the noise data, wherein the attribute parameters of the subjective evaluation indexes of the sound quality comprise loudness, roughness, jitter degree, sharpness and annoyance degree;
s3, optimizing the sound quality of the gas pressure regulating box, analyzing the subjective evaluation index of the noise data of the gas pressure regulating box, grading the noise energy, and optimizing the structure of the gas pressure regulating box according to different noise emission energies after grading so as to improve the sound quality of the gas pressure regulating box.
By adopting the technical scheme, the noises of different gas pressure regulating boxes are collected, classified and classified, and then different noise reduction methods are adopted for the gas pressure regulating boxes with different noise pollution characteristics respectively, so that the improvement of the acoustic subjective evaluation indexes of the middle and low pressure gas pressure regulating boxes with different noise pollution levels is realized, and the complaints are effectively reduced.
Optionally, the step S3 includes a step S31: when the equivalent continuous A sound level is less than 60dBA, the noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating tankThe noise energy is deviated to a middle-high frequency range, namely more than one third octave of 1000Hz, five surfaces of the inner wall of the gas pressure regulating box are fully adhered with a first sound absorbing material, the ground in the box is fully adhered with a second sound absorbing material, the first sound absorbing material is crushed into sizes of 2mm, 3mm and 4mm by utilizing a synthetic polymer foaming material, glue is mixed and added according to the proportion of 30 percent, 30 percent and 40 percent, a new material with the density of 220-300Kg/m3 is prepared in a mould pressing mode, and the using thickness is 15-20 mm; the second sound absorbing material is composed of a crushed stone combined with a polyurethane adhesive and has a density of 1600kg/m2The sound absorption floor of (2) is used with a thickness of 30-35 mm.
By adopting the technical scheme, when the equivalent continuous A sound level is less than 60dBA, the noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-high frequency band, namely more than one third octave of 1000Hz, the energy of the noise is biased to the middle and high frequency band, after the first sound absorption material and the second sound absorption material are adopted to process the air pressure regulating tank, wherein the first sound-absorbing material is made of artificially synthesized high-molecular foaming material, is crushed into particles with different particle sizes, is mixed by adopting three particle size compositions, so that more proper sound-absorbing gaps are formed among the first sound-absorbing materials, when noise passes through the first sound absorption material, vibration is transmitted to the interior of the first sound absorption material, and the vibration rubs with the complex inner foam holes of the first sound absorption material to be blocked, so that energy is attenuated, and therefore, noise sound waves are weakened, and the sound wave absorption effect of the first sound absorption material is shown; the sound absorption ground made of the polyurethane macadam has high strength, meanwhile, the porosity of the sound absorption ground made of the polyurethane macadam can reach 20-30%, further, noise energy can be absorbed to a large extent after passing through the polyurethane macadam ground, and the first sound absorption material and the second sound absorption material are matched with each other, so that the subjective evaluation index of external radiation noise of the gas pressure regulating box, namely loudness change, is improved by more than 4, sharpness change is more than 3, and the annoyance change is more than 15.
Optionally, the first sound absorbing material comprises at least one of FEF foaming, PE foaming, and epdm foaming.
By adopting the technical scheme, the FEF foaming, the PE foaming and the epdm foaming are adopted, so that the material taking and the material placing are convenient, the sound absorption effect is good, the heat resistance, the weather resistance and other aging resistance performance are excellent, the service life is long, and the cost performance is high.
Optionally, in step S3, the method further includes step S32: when the equivalent continuous A sound level is less than 60dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-low frequency band, namely below 1000Hz one-third octave, five surfaces of the inner wall of the gas pressure regulating tank are fully adhered with a third sound absorbing material, the ground in the tank is fully adhered with a fourth sound absorbing material, wherein the third sound absorbing material comprises a synthetic polymer foaming material, the synthetic polymer foaming material comprises at least one of FEF foaming, PE foaming and epdm foaming, the materials are crushed into 6mm, glue is mixed and added, a new material with the density of 180-260Kg/m3 is prepared in a mould pressing mode, and the use thickness is 25-30 mm; the fourth sound absorbing material composition comprises crushed stone and polyurethane binder, and is prepared to have a density of 1800kg/m2The sound absorption floor of (2) is used with a thickness of 35-50 mm.
By adopting the technical scheme, the noise energy is lower, the noise is biased to the middle and low frequency bands, and the transmission loss of the noise in the middle and low frequency bands is less in the transmission process, so that the synthetic polymer foam material with the particle size of 6mm is adopted in the third sound absorption material to prepare the sound absorption material of 180-260Kg/m3, the density is reduced, the void ratio is improved, the use thickness is increased, the use thickness is 25-30mm, meanwhile, the fourth sound absorption material adopts the sound absorption ground with the density of 1800Kg/m2, and the use thickness is 35-50mm, so that the absorption path of the noise in the middle and low frequency bands is prolonged, and the sound quality can be effectively improved. By adopting the scheme, the subjective evaluation index of the external radiation noise of the gas pressure regulating box, namely, the loudness is changed by about more than 4, the roughness is changed by about more than 0.5, and the annoyance is changed by about more than 10.
Optionally, in step S3, the method further includes step S33: when noise is generated by rigid connection between a fuel gas pressure regulating pipeline system and a fuel gas pressure regulating box structure and a pressure regulating pipeline in the fuel gas pressure regulating box, firstly, heavy materials are fully adhered to five surfaces of the inner wall of the fuel gas pressure regulating box, then, according to the frequency distribution of the noise, the first sound absorbing material or the third sound absorbing material is selected and adhered to the surface of the outer wall surface of the fuel gas pressure regulating box by adopting the steps S31 and S32; the heavy material is vinyl heavy rubber, the bulk density of the heavy material is not less than 2000 Kg/m3, and the thickness of the heavy material is not less than 2 mm.
By adopting the technical scheme, when the gas pressure regulating tank structure is in rigid connection with a pressure regulating pipeline in the gas pressure regulating tank, the propagation path of noise is solid propagation and air propagation, at this time, on the basis of the step S31 or the step S32, a heavy material is pasted on the side wall of the gas pressure regulating tank on the basis of the first sound absorption material or the second sound absorption material, wherein the heavy material is vinyl heavy rubber, the vinyl heavy rubber is a homogeneous and dense heavy material, and the vinyl heavy rubber is a flexible material which can effectively block the solid vibration propagation of noise, and on the basis of keeping the subjective evaluation index of noise improved in the step S31 or the step S32, the jitter degree is changed to be about 0.3 or more.
Optionally, in step S3, the method further includes step S34: when the equivalent continuous A sound level is in a gas pressure regulating box in the range of 60-70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating box, the noise energy is biased to a middle-high frequency range, namely more than 1000Hz one-third octave, a sixth sound absorbing material and an outer protective material are covered and installed on the outer wall surface of the gas pressure regulating box, wherein the sixth sound absorbing material comprises a light elastic artificially synthesized high polymer foaming material, the light elastic artificially synthesized high polymer foaming material comprises at least one of melamine foam and polyurethane sponge, the density is in the range of 10-50Kg/m3, and the use thickness is 30-40 mm; the outer protective material is a flexible outer protective material for protecting the sixth sound-absorbing material, and the sixth sound-absorbing material is wrapped when the sound-absorbing material is used.
By adopting the technical scheme, for the gas pressure regulating box with the equivalent continuous A sound level within the range of 60-70dBA, the outer side of the gas pressure regulating box is wrapped with the sixth sound-absorbing material which is a light elastic artificial synthetic polymer foam material and adopts melamine foam and polyurethane sponge, and the open-cell three-dimensional net structure ensures that the gas pressure regulating box has good sound absorption property, so that the sixth sound-absorbing material can absorb the noise energy generated in the gas pressure regulating box, and the sound quality of the gas pressure regulating box is improved; and outer protective material itself has the weatherability good, and intensity is fit for outdoor environment and frequent dismantlement, can stabilize the parcel to sixth sound absorbing material, prolongs sixth sound absorbing material's practical life. By adopting the scheme, the subjective evaluation index of the external radiation noise of the gas pressure regulating box, namely loudness change is about 6 or more, sharpness change is about 5 or more, and annoyance change is about 25 or more, can be effectively improved.
Optionally, in step S3, the method further includes step S35: when the equivalent continuous A sound level is in the range of 60-70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-low frequency band, namely below 1000Hz one-third octave, an outer protecting sound insulation material is covered on the outer side of the sixth sound absorption material, the outer protecting sound insulation material is a flexible outer protecting material for protecting the sixth sound absorption material, meanwhile, the bulk density is not lower than 1600Kg/m 3, the using thickness is not lower than 1mm, and the sixth sound absorption material is wrapped when the gas pressure regulating tank is used.
By adopting the technical scheme, for sound absorption and noise reduction with noise energy biased to a medium-low frequency band, an outer protecting and sound insulating material is additionally arranged on the basis of the outer side of the sixth coated fuel gas pressure regulating box, and the bulk density of the outer protecting and sound insulating material is not lower than 1600Kg/m3And the flexible outer protective material with the thickness not less than 1mm is used, so that the absorption path of noise is further improved on the basis of protecting the sixth sound absorption material, and the sound quality can be effectively improved. By adopting the scheme, the change of loudness, roughness and annoyance of the subjective evaluation index of external radiation noise is improved by about more than 5, 0.7 and 15.
Optionally, in step S3, the method further includes step S36: when the equivalent continuous A sound level of the gas pressure regulating tank is in the range of 60-70dBA, and noise is generated by the gas pressure regulating pipeline system and rigid connection between the structure of the gas pressure regulating tank and a pressure regulating pipeline in the gas pressure regulating tank, so that the radiation noise of the gas pressure regulating tank becomes a part which is not negligible in external radiation noise, heavy materials are required to be additionally installed according to the requirements in the steps S34 and S35.
By adopting the technical scheme, the number of layers of heavy materials can be selectively added according to the specific size of noise energy, so that the sound quality of the gas pressure regulating box is effectively improved.
Optionally, in step S3, the method further includes step S37: when the equivalent continuous A sound level is larger than 70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, and the combination of the steps S31 and S34 and the combination of the steps S32 and S35 are selected according to the frequency distribution of the noise to realize the subjective evaluation index for effectively improving the sound quality of the gas pressure regulating tank.
By adopting the technical scheme, the combination of the steps S31 and S34 and the combination of the steps S32 and S35 are selected to realize that the subjective evaluation indexes for effectively improving the sound quality of the gas pressure regulating tank, namely, the loudness is changed by about 5 or more, the sharpness is changed by about 4 or more, the roughness is changed by about 0.7 or more, the jitter degree is changed by about 0.3 or more, and the annoyance is changed by about 15 or more.
Optionally, in step S3, the method further includes step S38: when the equivalent continuous a sound level is greater than 70dBA of the gas pressure regulating tank, and noise is generated by the gas pressure regulating pipeline system itself and rigid connection between the structure of the gas pressure regulating tank and the pressure regulating pipeline in the gas pressure regulating tank, so that the radiation noise of the gas pressure regulating tank becomes a non-negligible part of the external radiation noise, a heavy material needs to be additionally installed according to the requirement in step S37.
By adopting the technical scheme, the number of layers of heavy materials can be selectively added on the basis of the combination of the steps S31 and S34 and the combination of the steps S32 and S35 according to the specific size of noise energy, so that the sound quality of the gas pressure regulating tank is effectively improved.
In summary, the present application includes the following beneficial technical effects:
1. the acoustic subjective evaluation indexes of the medium and low pressure fuel gas pressure regulating box with different noise pollution levels are improved by installing materials with different performances and components on the inner wall, the ground and the outer wall of the pressure regulating box;
2. the first sound absorption material adopts FEF foaming, PE foaming and epdm foaming, so that the material taking and the material placing are convenient, the sound absorption effect is good, the heat resistance, the weather resistance and other aging resistance performance are excellent, the service life is long, and the performance-price ratio is high.
Drawings
Fig. 1 is a schematic view of a flow structure according to an embodiment of the present application.
Fig. 2 is a flowchart of an optimization process for embodying the sound quality of the gas surge tank in the embodiment of the present application.
Detailed Description
The present application is described in further detail below with reference to the attached drawings.
The embodiment of the application discloses a method for improving acoustic subjective evaluation indexes of a medium-low pressure gas pressure regulating tank. Referring to fig. 1, a method for improving the acoustic subjective evaluation index of a medium-low pressure gas pressure regulating tank comprises the following steps:
s1, acquiring noise data of the gas pressure regulating box on external radiation, acquiring noise signals of different gas pressure regulating boxes in a working state by manual collection, wherein the noise collection mode can be performed by adopting a microphone and a recording device or a multi-channel collection device, processing the noise signals to obtain noise samples, classifying the noise according to a main noise generation source, and the main noise generation source according to the gas pressure regulating box can be divided into noise generated by a gas pressure regulating pipeline system in the gas pressure regulating box and noise generated by rigid connection between a gas pressure regulating box structure and a pressure regulating pipeline in the gas pressure regulating box;
s2, acquiring subjective evaluation indexes of the sound quality of the noise data, and acquiring 5 objective acoustic parameters of the sound quality, wherein the attribute parameters of the subjective evaluation indexes of the sound quality comprise loudness, roughness, jitter degree, sharpness and annoyance degree; specifically, the sound quality can be obtained by, but not limited to, converting the collected noise samples into playable ". wav" sound files by using MATLAB software, or importing the sound files directly collected by a sound recording device into sound quality analysis software HEAD Analyzer arms;
s3, optimizing the sound quality of the gas pressure regulating box, analyzing the subjective evaluation index of the noise data of the gas pressure regulating box, grading the noise energy, and optimizing the structure of the gas pressure regulating box according to different noise emission energies after grading so as to improve the sound quality of the gas pressure regulating box.
Referring to fig. 2, in step S3, step S31 is included: when the equivalent continuous A sound level is less than 60dBA, noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is deviated to a middle-high frequency band (more than 1000Hz one-third octave), five surfaces of the inner wall of the gas pressure regulating tank are fully attached with a first sound absorbing material, and the ground in the tank is fully attached with a second sound absorbing material; the first sound absorbing material is made of a synthetic polymer foam material, in the embodiment, the first sound absorbing material is selected from three of FEF (FEF) -foaming, PE (polyethylene) foaming and epdm-foaming, the FEF-foaming, the PE-foaming and the epdm-foaming are crushed into particles with the sizes of 2mm, 3mm and 4mm respectively, glue is mixed and added according to the proportion of 30%, 30% and 40%, the first sound absorbing material with the density of 220-300Kg/m3 is prepared in a mould pressing mode, and the thickness is 15-20 mm; in this embodiment, the second sound absorption material is composed of a sound absorption ground made of crushed stone and polyurethane binder, and having a density of 1600kg/m2, wherein the crushed stone has a particle size of 3mm-5mm (specifically, the crushed stone may have a particle size of 3mm, 3.25mm, 3.5mm, 3.75mm, 4mm, 4.25mm, 4.5mm, 4.75mm, 5mm, or other particle sizes within a range of 3mm-5 mm), and the dust content is less than 0.4 ‰ of the total weight, because commercially available crushed stones have particle sizes classified according to a particle size range, are not classified according to particle sizes, and cannot be purchased crushed stones having particle sizes of 3mm or 5mm, but are purchased in a particle size range, and the particle size range is suitable for this embodiment, so the embodiment is not limited by specific particle size values, and the second sound absorption material has a thickness of 30-35 mm.
Referring to fig. 2, in step S3, the method further includes step S32: when the equivalent continuous A sound level is less than 60dBA, noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-low frequency band (below 1000Hz one-third octave), five surfaces of the inner wall of the gas pressure regulating tank are fully adhered with a third sound absorbing material, the ground in the tank is fully adhered with a fourth sound absorbing material, wherein the third sound absorbing material comprises a synthetic high polymer foaming material, in the embodiment, the synthetic high polymer foaming material comprises three of FEF foaming, PE foaming and epdm foaming, the three synthetic high polymer foaming materials are crushed into particles with the particle size of 6mm, glue is added for mixing again after mixing, a new material with the density of 180-260Kg/m3 is prepared in a mould pressing mode, and the use thickness is 25-30 mm; the fourth sound absorption material comprises crushed stone and polyurethane adhesive, wherein the crushed stone has a particle size of 3mm-5mm (the particle size of the crushed stone can be 3mm, 3.25mm, 3.5mm, 3.75mm, 4mm, 4.25mm, 4.5mm, 4.75mm, 5mm or other particle sizes within the range of 3mm-5 mm), and the dust content accounts for less than 0.4 per mill of the total weight, since commercially available crushed stone is classified by particle size range, not by particle size, it is impossible to obtain crushed stone with a particle size of all 3mm or 5mm, and it is within a particle size range, and this particle size range is suitable for the present embodiment, therefore, no specific particle size is defined in the examples, and the second sound absorbing material is used in a thickness of 30 to 35mm to make a sound absorbing floor having a density of 1800kg/m2 and in a thickness of 35 to 50 mm.
In step S3, the method further includes step S33: when noise is generated by rigid connection between a gas pressure regulating pipeline system and a gas pressure regulating box structure and a pressure regulating pipeline in the gas pressure regulating box, and radiation noise of the gas pressure regulating box becomes a part which is not negligible in external radiation noise, firstly, heavy materials are fully pasted on five surfaces of the inner wall of the gas pressure regulating box, and then, according to the frequency distribution of the noise, the first sound absorption material or the third sound absorption material in the steps S31 and S32 is pasted and installed on the outer surface of the gas pressure regulating box; when the equivalent continuous A sound level is less than 60dBA, the noise energy is biased to a middle-high frequency range (more than 1000Hz one-third octave), five surfaces of the inner wall of the gas pressure regulating box are fully attached with heavy materials, the outer wall surface of the gas pressure regulating box is fully attached with a first sound absorbing material, and the ground in the gas pressure regulating box is fully attached with a second sound absorbing material; when the equivalent continuous A sound level is less than 60dBA, the noise energy is biased to a middle-low frequency band (below 1000Hz one-third octave), five surfaces of the inner wall of the gas pressure regulating box are fully adhered with heavy materials, the outer wall surface of the gas pressure regulating box is fully adhered with a third sound absorbing material, and the ground in the gas pressure regulating box is fully adhered with a fourth sound absorbing material; wherein the heavy material is vinyl heavy rubber, the heavy material is not less than 2000 Kg/m3, and the thickness is not less than 2 mm.
In step S3, the method further includes step S34: when the equivalent continuous A sound level is in a gas pressure regulating box within the range of 60-70dBA, noise is mainly generated by a gas pressure regulating pipeline system inside the gas pressure regulating box, the noise energy is deviated to a middle-high frequency range (more than 1000Hz one-third octave), a sixth sound absorbing material and an outer protective material are covered and installed on the outer wall surface of the gas pressure regulating box, wherein the sixth sound absorbing material comprises a light elastic artificially synthesized high polymer foaming material, the light elastic artificially synthesized high polymer foaming material comprises at least one of melamine foam and polyurethane sponge, the density is in the range of 10-50Kg/m3, the using thickness is 30-40mm, the sixth sound absorbing material does not need to be bonded on the box body and only needs to cover the surface of the box body, and a gap is allowed between the sixth sound absorbing material and the box body; outer protective material is outer protective material for the flexibility of protection sixth sound absorbing material, and itself has the weatherability good, intensity be fit for outdoor environment with frequently dismantle can, particularly, outer protective material chooses for use fire canvas, during the use with sixth sound absorbing material parcel can.
In step S3, the method further includes step S35: when the equivalent continuous A sound level is in the range of 60-70dBA, noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating box, noise energy is deviated to a middle-low frequency band (below 1000Hz one-third octave), an outer protecting sound insulation material covers the outer side of the sixth sound absorption material, and the outer protecting sound insulation material has good weather resistance and is suitable for outdoor environment and frequent disassembly in strength; the outer sound insulation material is a flexible outer sound insulation material for protecting the sixth sound absorption material, specifically, the outer sound insulation material can be a high molecular outer sound insulation material such as epdm rubber or shoulong rubber, meanwhile, the density of the outer sound insulation material is not lower than 1600Kg/m 3, the using thickness is not lower than 1mm, and the sixth sound absorption material is wrapped when the sound insulation material is used.
In step S3, the method further includes step S36: when the equivalent continuous A sound level of the gas pressure regulating box is in the range of 60-70dBA, and noise is generated by the rigid connection between the gas pressure regulating pipeline system and the gas pressure regulating box structure and the pressure regulating pipeline in the gas pressure regulating box, so that the radiation noise of the gas pressure regulating box becomes a part which is not negligible in external radiation noise, heavy materials are required to be additionally arranged according to the requirements in the steps S34 and S35, the number of layers of the heavy materials can be selectively additionally arranged according to the specific size of noise energy, namely when the noise energy is biased to a middle-high frequency band (more than 1000Hz one-third octave), the heavy materials are fully attached and additionally arranged on five surfaces of the inner wall of the gas pressure regulating box, and a sixth sound absorbing material and an external protecting material are arranged on the outer wall surface of the gas pressure regulating box in a covering manner; when the noise energy is deviated to a middle-low frequency range (below 1000Hz one-third octave), five surfaces of the inner wall of the gas pressure regulating box are fully adhered and additionally provided with heavy materials, and the outer wall surface of the gas pressure regulating box is covered and provided with a sixth sound absorbing material and an outer protecting and sound insulating material, so that the sound quality of the gas pressure regulating box is effectively improved.
In step S3, the method further includes step S37: when the equivalent continuous A sound level is larger than the gas pressure regulating tank with 70dBA, noise is mainly generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, and then the combination of the steps S31 and S34 is selected according to the frequency distribution of the noise energy; when the noise energy is deviated to a middle-high frequency range (more than 1000Hz one third octave), the five surfaces of the inner wall of the gas pressure regulating box are fully attached with a first sound absorbing material, the ground in the gas pressure regulating box is fully attached with a second sound absorbing material, and the outer wall surface of the box body is covered and installed with a sixth sound absorbing material and an outer protecting material; when the noise energy is deviated to a middle-low frequency range (below 1000Hz one-third octave), the fifth surface of the inner wall of the gas pressure regulating box is fully adhered with the third sound absorbing material, the ground in the gas pressure regulating box is fully adhered with the fourth sound absorbing material, and the outer wall surface of the gas pressure regulating box is covered and installed with the sixth sound absorbing material and the outer protecting sound insulating material, so that the subjective evaluation index of the sound quality of the gas pressure regulating box is effectively improved.
In step S3, the method further includes step S38: when the equivalent continuous a sound level is greater than 70dBA of the gas pressure regulating tank, and noise is generated by the gas pressure regulating pipeline system itself and rigid connection between the gas pressure regulating tank structure and the pressure regulating pipeline in the gas pressure regulating tank, so that the radiation noise of the gas pressure regulating tank becomes a part with non-negligible external radiation noise, heavy materials need to be additionally installed according to the requirements in step S37; when the noise energy is deviated to a middle-high frequency range (more than 1000Hz one third octave), heavy materials and first sound absorption materials are fully attached to five surfaces of the inner wall of the gas pressure regulating box, a second sound absorption material is fully attached to the ground in the gas pressure regulating box, and a sixth sound absorption material and an outer protection material are covered and installed on the outer wall surface of the box body; when the noise energy is deviated to a middle-low frequency range (below 1000Hz one-third octave), heavy materials and third sound absorbing materials are fully adhered to five surfaces of the inner wall of the gas pressure regulating box, a fourth sound absorbing material is fully adhered to the ground in the gas pressure regulating box, and a sixth sound absorbing material and an outer protecting and sound insulating material are covered and installed on the outer wall surface of the gas pressure regulating box, so that the subjective evaluation index of the sound quality of the gas pressure regulating box is effectively improved.
The implementation principle of the method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank in the embodiment of the application is as follows: the method has the advantages that different noise of the gas pressure regulating boxes is collected, classified and graded, and then different noise reduction methods are adopted for the gas pressure regulating boxes with different noise pollution characteristics respectively, so that the acoustic subjective evaluation indexes of the medium and low pressure gas pressure regulating boxes with different noise pollution levels are improved, and complaints are effectively reduced.
The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.
Claims (10)
1. A method for improving acoustic subjective evaluation indexes of a medium-low pressure fuel gas pressure regulating tank is characterized by comprising the following steps: the method comprises the following steps:
s1, acquiring noise data of the gas pressure regulating box on external radiation, acquiring a noise signal of the gas pressure regulating box in a working state by utilizing manpower, processing the noise signal to obtain a noise sample, and classifying the noise according to a main noise generation source, wherein the main noise generation source is divided into noise generated by a gas pressure regulating pipeline system in the gas pressure regulating box and noise generated by rigid connection among the gas pressure regulating pipeline system, the gas pressure regulating pipeline system and a gas pressure regulating box structure and a pressure regulating pipeline in the gas pressure regulating box;
s2, acquiring subjective evaluation indexes of the sound quality of the noise data, wherein the attribute parameters of the subjective evaluation indexes of the sound quality comprise loudness, roughness, jitter degree, sharpness and annoyance degree;
s3, optimizing the sound quality of the gas pressure regulating box, analyzing the subjective evaluation index of the noise data of the gas pressure regulating box, grading the noise energy, and optimizing the structure of the gas pressure regulating box according to different noise emission energies after grading so as to improve the sound quality of the gas pressure regulating box.
2. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 1 is characterized in that: in step S3, step S31 is included: when the equivalent continuous A sound level is less than 60dBA, noise is mainly generated by a gas pressure regulating pipeline system in a gas pressure regulating tank, the noise energy is deviated to a middle-high frequency range, namely more than 1000Hz one-third octave, five surfaces of the inner wall of the gas pressure regulating tank are fully attached with a first sound absorbing material, the ground in the tank is fully attached with a second sound absorbing material, the first sound absorbing material is crushed into sizes of 2mm, 3mm and 4mm by utilizing a synthetic polymer foaming material, glue is mixed and added according to the proportion of 30%, 30% and 40%, a new material with the density of 220-300Kg/m3 is prepared in a mould pressing mode, and the thickness is 15-20 mm; the second sound absorbing material is composed of a crushed stone combined with a polyurethane adhesive and has a density of 1600kg/m2The sound absorption floor of (2) is used with a thickness of 30-35 mm.
3. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 2 is characterized in that: the first sound absorbing material includes at least one of FEF foaming, PE foaming, and epdm foaming.
4. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 3 is characterized in that: in step S3, the method further includes step S32: when the equivalent continuous A sound level is less than 60dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-low frequency band, namely below 1000Hz one-third octave, five surfaces of the inner wall of the gas pressure regulating tank are fully attached with a third sound absorbing material, the ground in the tank is fully attached with a fourth sound absorbing material, wherein the third sound absorbing material comprises a synthetic high polymer foaming material, and the synthetic high polymer foaming material is artificially synthesizedThe molecular foaming material comprises at least one of FEF foaming, PE foaming and epdm foaming, is crushed into 6mm, is mixed with glue, is prepared into a new material with the density of 180-260Kg/m3 in a mould pressing mode, and has the use thickness of 25-30 mm; the fourth sound absorbing material composition comprises crushed stone and polyurethane binder, and is prepared to have a density of 1800kg/m2The sound absorption floor of (2) is used with a thickness of 35-50 mm.
5. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 4 is characterized in that: in step S3, the method further includes step S33: when noise is generated by rigid connection between a fuel gas pressure regulating pipeline system and a fuel gas pressure regulating box structure and a pressure regulating pipeline in the fuel gas pressure regulating box, firstly, heavy materials are fully adhered to five surfaces of the inner wall of the fuel gas pressure regulating box, then, according to the frequency distribution of the noise, the first sound absorbing material or the third sound absorbing material is selected and adhered to the surface of the outer wall surface of the fuel gas pressure regulating box by adopting the steps S31 and S32; the heavy material is vinyl heavy rubber, the bulk density of the heavy material is not less than 2000 Kg/m3, and the thickness of the heavy material is not less than 2 mm.
6. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 5 is characterized in that: in step S3, the method further includes step S34: when the equivalent continuous A sound level is in a gas pressure regulating box in the range of 60-70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating box, the noise energy is biased to a middle-high frequency range, namely more than 1000Hz one-third octave, a sixth sound absorbing material and an outer protective material are covered and installed on the outer wall surface of the gas pressure regulating box, wherein the sixth sound absorbing material comprises a light elastic artificially synthesized high polymer foaming material, the light elastic artificially synthesized high polymer foaming material comprises at least one of melamine foam and polyurethane sponge, the density is in the range of 10-50Kg/m3, and the use thickness is 30-40 mm; the outer protective material is a flexible outer protective material for protecting the sixth sound-absorbing material, and the sixth sound-absorbing material is wrapped when the sound-absorbing material is used.
7. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 6 is characterized in that: in step S3, the method further includes step S35: when the equivalent continuous A sound level is in the range of 60-70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, the noise energy is biased to a middle-low frequency band, namely below 1000Hz one-third octave, an outer protecting sound insulation material is covered on the outer side of the sixth sound absorption material, the outer protecting sound insulation material is a flexible outer protecting material for protecting the sixth sound absorption material, meanwhile, the bulk density is not lower than 1600Kg/m 3, the using thickness is not lower than 1mm, and the sixth sound absorption material is wrapped when the gas pressure regulating tank is used.
8. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 7 is characterized in that: in step S3, the method further includes step S36: when the equivalent continuous A sound level of the gas pressure regulating tank is in the range of 60-70dBA, and noise is generated by the gas pressure regulating pipeline system and rigid connection between the structure of the gas pressure regulating tank and a pressure regulating pipeline in the gas pressure regulating tank, so that the radiation noise of the gas pressure regulating tank becomes a part which is not negligible in external radiation noise, heavy materials are required to be additionally installed according to the requirements in the steps S34 and S35.
9. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 8 is characterized in that: in step S3, the method further includes step S37: when the equivalent continuous A sound level is larger than 70dBA, noise is generated by a gas pressure regulating pipeline system in the gas pressure regulating tank, and the combination of the steps S31 and S34 and the combination of the steps S32 and S35 are selected according to the frequency distribution of the noise to realize the subjective evaluation index for effectively improving the sound quality of the gas pressure regulating tank.
10. The method for improving the acoustic subjective evaluation index of the medium-low pressure gas pressure regulating tank according to claim 8 is characterized in that: in step S3, the method further includes step S38: when the equivalent continuous a sound level is greater than 70dBA of the gas pressure regulating tank, and noise is generated by the gas pressure regulating pipeline system itself and rigid connection between the structure of the gas pressure regulating tank and the pressure regulating pipeline in the gas pressure regulating tank, so that the radiation noise of the gas pressure regulating tank becomes a non-negligible part of the external radiation noise, a heavy material needs to be additionally installed according to the requirement in step S37.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4755416A (en) * | 1986-05-16 | 1988-07-05 | Matec Holding Ag | Process for constructing a structural element that absorbs airborne sound |
| JPH1173190A (en) * | 1997-08-29 | 1999-03-16 | Japan Aviation Electron Ind Ltd | Silencer |
| US20090038881A1 (en) * | 2007-08-06 | 2009-02-12 | Mazda Motor Corporation | Sound-absorbing material, production method for sound-absorbing material, and sound-absorbing structure |
| US20090180627A1 (en) * | 2007-12-21 | 2009-07-16 | Airbus Deutschland Gmbh | Active sound blocker |
| EP2570664A2 (en) * | 2011-09-13 | 2013-03-20 | Black & Decker Inc. | Air Ducting Shroud for Cooling an Air Compressor Pump and Motor |
| CN203532189U (en) * | 2013-08-22 | 2014-04-09 | 广东美的制冷设备有限公司 | Low-noise variable frequency air conditioner compressor |
| CN103826183A (en) * | 2014-02-24 | 2014-05-28 | 东莞凤合凰电声科技有限公司 | Band-pass type bass loudspeaker box and adjusting method thereof |
| CN106558302A (en) * | 2015-09-29 | 2017-04-05 | 国网智能电网研究院 | A kind of sound source device noise-reduction method |
| CN108074560A (en) * | 2018-01-22 | 2018-05-25 | 深圳可朗声科技有限公司 | Sound absorber and its noise reduction furniture in a kind of broadband room |
| CN110688712A (en) * | 2019-10-11 | 2020-01-14 | 湖南文理学院 | Evaluation index for objective annoyance degree of automobile wind vibration noise sound quality and calculation method thereof |
-
2020
- 2020-09-18 CN CN202010985186.6A patent/CN112116901B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4755416A (en) * | 1986-05-16 | 1988-07-05 | Matec Holding Ag | Process for constructing a structural element that absorbs airborne sound |
| JPH1173190A (en) * | 1997-08-29 | 1999-03-16 | Japan Aviation Electron Ind Ltd | Silencer |
| US20090038881A1 (en) * | 2007-08-06 | 2009-02-12 | Mazda Motor Corporation | Sound-absorbing material, production method for sound-absorbing material, and sound-absorbing structure |
| US20090180627A1 (en) * | 2007-12-21 | 2009-07-16 | Airbus Deutschland Gmbh | Active sound blocker |
| EP2570664A2 (en) * | 2011-09-13 | 2013-03-20 | Black & Decker Inc. | Air Ducting Shroud for Cooling an Air Compressor Pump and Motor |
| CN203532189U (en) * | 2013-08-22 | 2014-04-09 | 广东美的制冷设备有限公司 | Low-noise variable frequency air conditioner compressor |
| CN103826183A (en) * | 2014-02-24 | 2014-05-28 | 东莞凤合凰电声科技有限公司 | Band-pass type bass loudspeaker box and adjusting method thereof |
| CN106558302A (en) * | 2015-09-29 | 2017-04-05 | 国网智能电网研究院 | A kind of sound source device noise-reduction method |
| CN108074560A (en) * | 2018-01-22 | 2018-05-25 | 深圳可朗声科技有限公司 | Sound absorber and its noise reduction furniture in a kind of broadband room |
| CN110688712A (en) * | 2019-10-11 | 2020-01-14 | 湖南文理学院 | Evaluation index for objective annoyance degree of automobile wind vibration noise sound quality and calculation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 颜丹平;高顺利;朱凌;于燕平;韩颐军;赵欣;: "天然气调压站的噪声控制实践", 煤气与热力, no. 12, 15 December 2008 (2008-12-15) * |
| 高春梅;乔斌;李清;颜丹平;: "天然气调压站噪声分析与降噪措施", 煤气与热力, no. 12, 15 December 2019 (2019-12-15) * |
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