Technology innovation
Noise control technology
Source：original
Editor：富生源
Release time：2017-09-01 16:29
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Introduction to Noise Control Technology
Physical definition
Noise is the sound that is emitted when the body is made irregular.
Physiological definition
Those who hinder the normal rest, learning and working voice, as well as people to listen to the voice of the sound of interference. In this sense, there are many sources of noise. The sound of the car on the street, the sound of the quiet library, the sound of the building site, and the loud noise of the neighbor's TV.
The overall noise is the object of vibration production.
First, the harm of noise
Noise gives a physical and psychological harm, the noise of the malignant stimulus, seriously affect our sleep quality, and will lead to dizziness, headache, insomnia, dreams, memory loss, inattention and other symptoms of neurasthenia and nausea , To spit, stomach pain, abdominal distension, loss of appetite and other gastrointestinal symptoms. Nutritionists found that the noise can also make the body of vitamins, trace elements nitrogen acid, glutamic acid, lysine and other essential nutrients consumption increased, affecting health; noise is the increase in adrenal secretion increased heart rate, Blood pressure rise, easily lead to heart disease; the same time, noise can make people saliva, gastric juice secretion decreased gastric acid, resulting in gastric ulcer and duodenal ulcer.
Second, the basic principles of noise control
Environmental noise pollution is generally composed of sound source, transmission and acceptance of the three basic links. Therefore, the noise control must be the three links as a system for research.
The sound source can be a single, it can be a number of simultaneous role; transmission is often more than one, and not fixed; the recipient may be a person, it may be a number of sensitive equipment, the noise response is also different. Therefore, in considering the issue, it is necessary to pay attention to this statistical nature, but also consider the individual characteristics.
1, reduce the noise of the sound source is the most fundamental control of noise control measures. Through the in-depth study of sound source sound mechanism and operation of machinery and equipment, the development of new low-noise equipment to reduce the excitation force, or change the operating procedures and improve the processing technology, can significantly reduce the environmental noise.
2, the sound transmission path control is commonly used noise reduction means. In the path of noise transmission, set the obstacles to prevent the spread of sound waves, laying sound absorption material to increase the sound energy loss, or by reflection, refraction to change the direction of propagation of sound waves. In the noise control project often used in the effective technology of sound absorption, sound insulation, damping and vibration isolation and so on. Common sound-absorbing walls, sound-absorbing ceilings, sound insulation barriers, sound barriers, sound insulation windows, muffler and vibration isolation floor, etc., is the specific application of these technologies.
3, in some cases, the noise is particularly strong, in the use of these measures, still can not meet the requirements, or work process, inevitably there is noise, you need to take measures from the recipient control point of view. For people, you can wear earplugs, earmuffs, active muffler helmets, etc .; for precision instruments and equipment, can be placed in the sound insulation or vibration isolation platform.
Third, the general principles of noise control
Noise control design should generally adhere to the scientific, advanced and economic principles.
1, scientific: first of all should correctly analyze the sound mechanism and sound source characteristics, is aerodynamic noise, mechanical noise or electromagnetic noise; or high frequency noise or low frequency noise. The sound source for a detailed spectrum analysis, according to the spectral characteristics to determine the corresponding measures.
2, advanced: This is the design of the pursuit of important goals, but should be based on the possible implementation. Control technology can not affect the technical performance and process requirements of the original equipment, and to meet the equipment for maintenance and ventilation cooling requirements.
3, economy: economic rationality is also one of the objectives of the pursuit of design. Noise pollution is physical pollution, that is, sound energy pollution, control objectives in order to achieve the allowable standard value, but the national standard has its stage, we must consider the economic capacity at that time. The sound source for spectrum analysis after symptomatic treatment, and strive to the lowest capital investment and get the most satisfactory governance effect.
Fourth, the noise prevention method
China's psychology that the control of the noise environment, in addition to taking into account the human factors, but also take into account the economic and technical feasibility. Full noise control, must consider the noise source, acoustic way, by the sound of the entire system. Measures to control noise may be directed to the above three parts or any part thereof.
Noise control includes:
(1) reduce the noise of the sound source, industry, transportation can choose low noise production equipment and improve the production process, or change the noise source movement (such as damping, vibration and other measures to reduce the vibration of solid body).
(2) to reduce noise in the acoustic way, to control the spread of noise, to change the sound source has been issued by the noise transmission, such as the use of sound-absorbing, noise, sound barrier, vibration isolation and other measures, and rational planning of urban and architectural layout.
(3) the noise of the speaker or the sound organ, the sound source and the means of transmission can not take measures, or take the acoustics measures still can not achieve the desired effect, the need for the sound or the sound organ to take protective measures , Such as long-term occupational noise exposure workers can wear earplugs, earmuffs or helmets and other ear protectors.
Some ways to prevent and control noise pollution
(1) to create a noise forest
(2) the noise pollution of the enterprise removed from the urban areas
(3) the source of prevention, transmission process to reduce
Fifth, the basic procedures of noise control
The basic program of noise control should start from the sound source characteristic investigation, through the spectrum analysis of the sound source, the transmission route analysis, the determination of noise reduction and a series of steps and then select the best program, and finally the noise control project evaluation.
Physical definition
Noise is the sound that is emitted when the body is made irregular.
Physiological definition
Those who hinder the normal rest, learning and working voice, as well as people to listen to the voice of the sound of interference. In this sense, there are many sources of noise. The sound of the car on the street, the sound of the quiet library, the sound of the building site, and the loud noise of the neighbor's TV.
The overall noise is the object of vibration production.
First, the harm of noise
Noise gives a physical and psychological harm, the noise of the malignant stimulus, seriously affect our sleep quality, and will lead to dizziness, headache, insomnia, dreams, memory loss, inattention and other symptoms of neurasthenia and nausea , To spit, stomach pain, abdominal distension, loss of appetite and other gastrointestinal symptoms. Nutritionists found that the noise can also make the body of vitamins, trace elements nitrogen acid, glutamic acid, lysine and other essential nutrients consumption increased, affecting health; noise is the increase in adrenal secretion increased heart rate, Blood pressure rise, easily lead to heart disease; the same time, noise can make people saliva, gastric juice secretion decreased gastric acid, resulting in gastric ulcer and duodenal ulcer.
Second, the basic principles of noise control
Environmental noise pollution is generally composed of sound source, transmission and acceptance of the three basic links. Therefore, the noise control must be the three links as a system for research.
The sound source can be a single, it can be a number of simultaneous role; transmission is often more than one, and not fixed; the recipient may be a person, it may be a number of sensitive equipment, the noise response is also different. Therefore, in considering the issue, it is necessary to pay attention to this statistical nature, but also consider the individual characteristics.
1, reduce the noise of the sound source is the most fundamental control of noise control measures. Through the in-depth study of sound source sound mechanism and operation of machinery and equipment, the development of new low-noise equipment to reduce the excitation force, or change the operating procedures and improve the processing technology, can significantly reduce the environmental noise.
2, the sound transmission path control is commonly used noise reduction means. In the path of noise transmission, set the obstacles to prevent the spread of sound waves, laying sound absorption material to increase the sound energy loss, or by reflection, refraction to change the direction of propagation of sound waves. In the noise control project often used in the effective technology of sound absorption, sound insulation, damping and vibration isolation and so on. Common sound-absorbing walls, sound-absorbing ceilings, sound insulation barriers, sound barriers, sound insulation windows, muffler and vibration isolation floor, etc., is the specific application of these technologies.
3, in some cases, the noise is particularly strong, in the use of these measures, still can not meet the requirements, or work process, inevitably there is noise, you need to take measures from the recipient control point of view. For people, you can wear earplugs, earmuffs, active muffler helmets, etc .; for precision instruments and equipment, can be placed in the sound insulation or vibration isolation platform.
Third, the general principles of noise control
Noise control design should generally adhere to the scientific, advanced and economic principles.
1, scientific: first of all should correctly analyze the sound mechanism and sound source characteristics, is aerodynamic noise, mechanical noise or electromagnetic noise; or high frequency noise or low frequency noise. The sound source for a detailed spectrum analysis, according to the spectral characteristics to determine the corresponding measures.
2, advanced: This is the design of the pursuit of important goals, but should be based on the possible implementation. Control technology can not affect the technical performance and process requirements of the original equipment, and to meet the equipment for maintenance and ventilation cooling requirements.
3, economy: economic rationality is also one of the objectives of the pursuit of design. Noise pollution is physical pollution, that is, sound energy pollution, control objectives in order to achieve the allowable standard value, but the national standard has its stage, we must consider the economic capacity at that time. The sound source for spectrum analysis after symptomatic treatment, and strive to the lowest capital investment and get the most satisfactory governance effect.
Fourth, the noise prevention method
China's psychology that the control of the noise environment, in addition to taking into account the human factors, but also take into account the economic and technical feasibility. Full noise control, must consider the noise source, acoustic way, by the sound of the entire system. Measures to control noise may be directed to the above three parts or any part thereof.
Noise control includes:
(1) reduce the noise of the sound source, industry, transportation can choose low noise production equipment and improve the production process, or change the noise source movement (such as damping, vibration and other measures to reduce the vibration of solid body).
(2) to reduce noise in the acoustic way, to control the spread of noise, to change the sound source has been issued by the noise transmission, such as the use of sound-absorbing, noise, sound barrier, vibration isolation and other measures, and rational planning of urban and architectural layout.
(3) the noise of the speaker or the sound organ, the sound source and the means of transmission can not take measures, or take the acoustics measures still can not achieve the desired effect, the need for the sound or the sound organ to take protective measures , Such as long-term occupational noise exposure workers can wear earplugs, earmuffs or helmets and other ear protectors.
Some ways to prevent and control noise pollution
(1) to create a noise forest
(2) the noise pollution of the enterprise removed from the urban areas
(3) the source of prevention, transmission process to reduce
Fifth, the basic procedures of noise control
The basic program of noise control should start from the sound source characteristic investigation, through the spectrum analysis of the sound source, the transmission route analysis, the determination of noise reduction and a series of steps and then select the best program, and finally the noise control project evaluation.