CN103226037B - Method of determining noise measuring point arrangement based on mean deviation - Google Patents
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- CN103226037B CN103226037B CN201310122447.1A CN201310122447A CN103226037B CN 103226037 B CN103226037 B CN 103226037B CN 201310122447 A CN201310122447 A CN 201310122447A CN 103226037 B CN103226037 B CN 103226037B
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Abstract
The invention relates to the field of noise measuring, in particular to a method of noise measuring point arrangement. The method of determining the noise measuring point arrangement based on a mean deviation comprises the steps that a mean deviation threshold of the measuring point arrangement is obtained according to a noise measuring accuracy class; a measuring distance is determined; a measuring surface is obtained; positions and quantity of initial noise measuring points are determined according to the accuracy class and the measuring distance; a mean deviation measured value is calculated according to a noise measuring result; the mean deviation measured value and the mean deviation threshold of the measuring point arrangement are compared; measuring point arrangement completion or measuring point increase is decided; and the measuring points are rearranged until the mean deviation measured value is smaller than or equal to the threshold. The method is used for determining the noise measuring point arrangement based on the mean deviation, so that the measuring uncertainty caused by noise measuring point arrangement factors can be quantified, and can be controlled effectively; and therefore, the uncertainty of a noise sound power level measuring result can meet an uncertainty requirement specified by the corresponding accuracy class.
Description
Technical field
The present invention relates to noise measurement field, relate in particular to a kind of method that noise measuring point is arranged.
Background technology
In the standard of existing a series of acoustic sound pressure methods mensuration Sound Power Level of Noise Source, various types of machine and equipments have been included, these basic standards have stipulated to be suitable for measuring under varying environment and class of accuracy the acoustics requirement of sound power level, comprise installation and the condition of work of acoustic condition and instrument, the measuring process that should follow and tested machine.These standards are not all stipulated the relation of the uncertainty of measurement of noise measuring point layout class of accuracy requirement corresponding with it, namely there is no the uncertainty of measurement being caused by noise measuring point layout factor to be quantized and propose limit value requirement.
Such as at GB/T 3767-1996(ISO 3744:1994, MOD) 7.2.2 < < hemisphere measures the upper additional microphone position > > in surface and 7.3.2 < < and at parallelepipedon, measures in additional microphone position > >, to be defined on surface and under following situations, need additional microphone position:
The scope of the sound pressure level value a) recording on basic microphone position, the dB between the highest and minimum sound pressure level is poor surpasses basic measuring point number;
B) sound source radiation noise has very strong directive property;
C) a large sound source, its noise only a very little part by sound source to external radiation, the machine of periphery seal opening for example.
In above-mentioned three kinds of situations, though a) have the regulation on numerical value, noise measuring point number is not associated with uncertainty of measurement, and b) and c) be only to stipulate qualitatively, do not quantize.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of method of determining noise measuring point layout based on mean bias, under the accuracy of measurement grade in regulation, based on mean bias, determine noise measuring point layout, thereby can make the uncertainty of Noisy acoustic power level measurement result can meet the uncertainty requirement that corresponding class of accuracy is stipulated.
The present invention is achieved in that a kind of method of determining noise measuring point layout based on mean bias, comprises the following steps:
Based on mean bias, determine the method that noise measuring point is arranged, comprise the following steps:
Step 1, according to the class of accuracy of the selected noise measurement of the national standard of noise measurement, the maximum interference standard uncertainty of finding standard uncertainty limit value and being caused by other disturbing factors except measuring point is arranged factor according to the class of accuracy of noise measurement, combined standard uncertainty limit value, maximum interference standard uncertainty and the maximum standard uncertainty being caused by measuring distance calculate the standard deviation threshold of the sound pressure level mean value that all microphone positions place records, and are called for short mean bias threshold value;
Step 2, according to the shape of the class of accuracy of noise measurement, benchmark body and position and acoustic enviroment, determine that measuring distance measures surface to obtain;
Step 3, according to the measurement surface of the class of accuracy of noise measurement and acquisition, determine position and the number of initial noise measuring point, at each measuring point, arrange a microphone;
Step 4, carry out noise measurement, according to the numerical evaluation mean bias measured value measuring;
Step 5, comparison mean bias measured value and measuring point are arranged mean bias threshold value, and select according to following two kinds of situations:
1) mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges;
2) mean bias measured value is greater than mean bias threshold value, increases measuring point number and rearranges point position, and return to step 2 and re-start measurement, until mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges.
In described step 1, calculate mean bias threshold value
, be specially:
In formula:
for standard uncertainty limit value corresponding to the class of accuracy of selected noise measurement;
The maximum interference standard uncertainty being caused by other disturbing factors except measuring point is arranged factor during for noise measurement;
the maximum distance criterion uncertainty being caused by measuring distance while arranging for noise measuring point.
In described step 4, calculate mean bias measured value
, be specially:
In formula:
for measuring surface the
ithe sound pressure level that individual microphone position place records;
the sound pressure level mean value recording for measuring surperficial all microphone positions place,
；
number for measuring point.
Surface is measured for hemisphere in described measurement surface, and the concrete method for arranging of measuring point is that position and the number of initial noise measuring point are arranged according to corresponding national standard or iso standard; When mean bias measured value is greater than mean bias threshold value, the geometric center of hemisphere projection on reflecting surface of take is initial point, and from initial point, on reflecting surface, drawing arbitrarily a straight line is x axle; Along x axle, be rotated counterclockwise 90 ° for y axle; Perpendicular to reflecting surface be z axle, initial noise measuring point be take to the measuring point that z axle obtains newly increasing as axis Rotate 180 °, original initial noise measuring point keeps former invariant position, the measuring point that position coincides is appointed and is got a bit.
Described measurement surface is rectangular hexahedron measurement surface, the concrete method for arranging of measuring point is, according to the class of accuracy value of noise measurement, measuring distance d, size be than number k and the amplitude L that successively decreases, and arranges position and the number of initial noise measuring point according to corresponding national standard or iso standard; When mean bias measured value is greater than mean bias threshold value, the L of take successively reduces k value as amplitude, by measuring surface each face except bottom surface, be again separated into equidimension rectangular area unit and arrange measuring point, the measuring point that falls into bottom surface is cancelled, until mean bias measured value is less than or equal to mean bias threshold value.
The present invention is based on mean bias and determine that the method for noise measuring point layout can make the uncertainty of measurement being caused by noise measuring point layout factor be quantized, the uncertainty of measurement being caused by measuring point layout factor like this can be effectively controlled, thereby can make the uncertainty of Noisy acoustic power level measurement result can meet the uncertainty requirement that corresponding class of accuracy is stipulated.
Accompanying drawing explanation
Fig. 1 the present invention is based on mean bias to determine that in the embodiment 1 of the method that noise measuring point is arranged, hemisphere is measured the main schematic diagram of looking of surperficial measuring point layout; Benchmark body sequence number is measuring point sequence number
Fig. 2 the present invention is based on mean bias to determine that in the embodiment 1 of the method that noise measuring point is arranged, hemisphere is measured surperficial measuring point layout schematic top plan view; Benchmark body sequence number is measuring point sequence number
In Fig. 1, Fig. 2:
Benchmark body
l 1*
l 2*
l 3(m) be 0.80 * 0.60 * 0.60;
Hemisphere meter radius surface
r(m) be 2.
Fig. 3 the present invention is based on the measuring point initial placement schematic diagram that mean bias is determined rectangular hexahedron in the embodiment 2 of the method that noise measuring point is arranged; In benchmark body, sequence number is measuring point sequence number
Fig. 4 the present invention is based on mean bias to determine that the measuring point of rectangular hexahedron in the embodiment 2 of the method that noise measuring point is arranged rearranges schematic diagram; In benchmark body, sequence number is measuring point sequence number
In Fig. 3, Fig. 4:
Benchmark body
l 1*
l 2*
l 3(m) be 0.80 * 0.60 * 0.60;
Rectangular hexahedron is measured surface
l 1*
l 2*
l 3(m) be 2.80 * 2.60 * 1.60.
In figure: 1 measures surface, 2 benchmark bodies.
Embodiment
Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiment are only not used in and limit the scope of the invention for the present invention is described.In addition should be understood that those skilled in the art can make various changes or modifications the present invention after having read the content of the present invention's statement, these equivalent form of values fall within the application's appended claims limited range equally.
Embodiment 1
Based on mean bias, determine the method that noise measuring point is arranged, comprise the following steps:
Step 1, according to the class of accuracy of the selected noise measurement of the national standard of noise measurement, the maximum interference standard uncertainty of finding standard uncertainty limit value and being caused by other disturbing factors except measuring point is arranged factor according to the class of accuracy of noise measurement, combined standard uncertainty limit value, maximum interference standard uncertainty and the maximum standard uncertainty being caused by measuring distance calculate the standard deviation threshold of the sound pressure level mean value that all microphone positions place records, and are called for short mean bias threshold value;
Step 2, according to the shape of the class of accuracy of noise measurement, benchmark body 2 and position and acoustic enviroment, determine that measuring distance measures surface 1 to obtain;
Step 3, according to the measurement surface of the class of accuracy of noise measurement and acquisition, determine position and the number of initial noise measuring point, at each measuring point, arrange a microphone;
Step 4, carry out noise measurement, according to the numerical evaluation mean bias measured value measuring;
Step 5, comparison mean bias measured value and measuring point are arranged mean bias threshold value, and select according to following two kinds of situations:
1) mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges;
2) mean bias measured value is greater than mean bias threshold value, increases measuring point number and rearranges point position, and return to step 2 and re-start measurement, until mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges.
As shown in Figure 1, 2, in the present embodiment, the hemisphere of take is measured surface and according to this method, is carried out noise measuring point layout as example.
The noise measurement class of accuracy that step 1, the present embodiment are selected is 2 grades, referring to the vibration of < < internal combustion engine noise and control > > (Wu Yanting, Yuan Wei flat sennit, Beijing: China Machine Press, 1999) description in, corresponding standard uncertainty limit value
for 1.5dB.Theoretical analysis and experimental verification show: the maximum interference standard uncertainty being caused by other disturbing factors except measuring point is arranged factor during noise measurement
for
dB, the maximum distance criterion uncertainty that noise measuring point is caused by measuring distance while arranging
for 0.6dB,
Mean bias threshold value
=0.8(dB),
≤ 0.8(dB).
Step 2, according to the shape of 2 grades of accuracy, benchmark body 2 and position and acoustic enviroment, determine that measuring distance measures radius is 2m, hemisphere is measured surface;
Step 3, according to GB GB/T 3767-1996(ISO 3744:1994, MOD) 7.2.2 < < hemisphere is measured the upper additional microphone position > > in surface, on measurement surface, with homalographic, connect 10 initial noise measuring points are set, the geometric center of hemisphere projection on reflecting surface of take is initial point, and from initial point, on reflecting surface, drawing arbitrarily a straight line is x axle; Along x axle, be rotated counterclockwise 90 ° for y axle; Perpendicular to reflecting surface be z axle, r is for measuring radius, hemisphere is measured surperficial radius; The coordinate position of 10 initial noise measuring points is as shown in table 1 below,
Table 1
Step 4, carry out noise measurement, the sound pressure level of 10 initial noise measuring points that record is as shown in table 2 below,
Table 2
According to calculate=1.20 (dB) of data substitution formula in table 2
Step 5, comparison
with
, because
>
need to increase measuring point, because measure surface in the present embodiment for hemisphere measurement surface, when mean bias measured value is greater than mean bias threshold value, 10 initial noise measuring points be take to the measuring point newly increasing that z axle obtains as axis Rotate 180 °, original initial noise measuring point keeps former invariant position, and the measuring point that position coincides is appointed and got a bit.
So original 10 measuring points keep original position, 10 newly-increased measuring point sequence numbers are that 11 ~ 20 coordinate positions are as shown in table 3 below, and the 10th point position overlaps with the 20th point position, gets a bit:
Table 3
Increase the noise measurement of measuring point newly, the sound pressure level of 19 measuring points that record is as shown in table 4 below,
Table 4
According to data substitution formula in table 4, calculate
=0.77 (dB)
Again compare
with
, because
≤
, measuring point deploys, and completes this operation.
Embodiment 2
As shown in Figure 3,4, in the present embodiment, the rectangular hexahedron of take is measured surface and according to this method, is carried out noise measuring point layout as example.
The noise measurement class of accuracy that step 1, the present embodiment are selected is 2 grades, referring to the vibration of < < internal combustion engine noise and control > > (Wu Yanting, Yuan Wei flat sennit, Beijing: China Machine Press, 1999) description in, corresponding standard uncertainty limit value
for 1.5dB.Theoretical analysis and experimental verification show: the maximum interference standard uncertainty being caused by other disturbing factors except measuring point is arranged factor during noise measurement
for
dB, the maximum distance criterion uncertainty that noise measuring point is caused by measuring distance while arranging
for 0.6dB;
Mean bias threshold value
=0.8(dB),
≤ 0.8(dB).
Step 2, according to the shape of 2 grades of accuracy, benchmark body and position and acoustic enviroment, determine that measuring distance is 1m, rectangular hexahedron is measured surface.According to GB GB/T 3767-1996(ISO 3744:1994, MOD); Appendix C < < parallelepipedon is measured lip-deep microphone array > >, the size of rectangular hexahedron is 3 than number k maximal value, and the amplitude of the successively decreasing L setting in the present embodiment is 0.5;
Step 3, according to GB GB/T 3767-1996(ISO 3744:1994, MOD); Appendix C < < parallelepipedon is measured lip-deep microphone array > >, each face by rectangular hexahedron except bottom surface is separated into equidimension rectangular area unit, it is 3.00m that the length of side of rectangular area unit is no more than k*d, on each center of each rectangular area unit and summit, arrange a measuring point, the measuring point that falls into bottom surface is cancelled, amount to 9 measuring points, as shown in Figure 3;
Step 4, carry out noise measurement, the sound pressure level of 9 initial noise measuring points that record is as shown in table 5 below,
Table 5
According to data substitution formula in table 2, calculate
=0.95 (dB)
Step 5, comparison
with
, because
>
, need to increase measuring point, because measure surface in the present embodiment, be rectangular hexahedron, take 0.5 as amplitude general
kvalue is reduced to 2.5, by measuring surface each face except bottom surface, is again separated into equidimension rectangular area unit, and it is 2.50m that the length of side of rectangular area unit is no more than 2.5d, and again in former mode, arranges measuring point, as shown in Figure 4.Re-start noise measurement, the sound pressure level of 21 measuring points that record, as shown in table 6 below,
Table 6
According to data substitution formula in table 6, calculate
=0.57 (dB)
Again compare
with
, because
≤
, measuring point deploys, and completes this operation.
Claims (5)
1. based on mean bias, determine the method that noise measuring point is arranged, it is characterized in that, comprise the following steps:
Step 1, according to the class of accuracy of the selected noise measurement of the national standard of noise measurement, the maximum interference standard uncertainty of finding standard uncertainty limit value and being caused by other disturbing factors except measuring point is arranged factor according to the class of accuracy of noise measurement, combined standard uncertainty limit value, maximum interference standard uncertainty and the maximum standard uncertainty being caused by measuring distance calculate the standard deviation threshold of the sound pressure level mean value that all microphone positions place records, and are called for short mean bias threshold value;
Step 2, according to the shape of the class of accuracy of noise measurement, benchmark body and position and acoustic enviroment, determine that measuring distance measures surface to obtain;
Step 3, according to the measurement surface of the class of accuracy of noise measurement and acquisition, determine position and the number of initial noise measuring point, at each measuring point, arrange a microphone;
Step 4, carry out noise measurement, according to the numerical evaluation mean bias measured value measuring;
Step 5, comparison mean bias measured value and mean bias threshold value, and select according to following two kinds of situations:
Mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges;
Mean bias measured value is greater than mean bias threshold value, increases measuring point number and rearranges point position, and return to step 2 and re-start measurement, until mean bias measured value is less than or equal to mean bias threshold value, completes measuring point and arranges.
2. the method for determining noise measuring point layout based on mean bias as claimed in claim 1, is characterized in that: in described step 1, calculate mean bias threshold value s
a, be specially:
In formula: s
lfor standard uncertainty limit value corresponding to the class of accuracy of selected noise measurement;
S
bthe maximum interference standard uncertainty being caused by other disturbing factors except measuring point is arranged factor during for noise measurement;
S
cthe maximum distance criterion uncertainty being caused by measuring distance while arranging for noise measuring point.
3. as claimed in claim 1ly based on mean bias, determine the method that noise measuring point is arranged, it is characterized in that: in described step 4, calculate mean bias measured value s (L '
μ m), be specially:
In formula: L '
pifor measuring surperficial i the sound pressure level that microphone position place records;
L '
μ mthe sound pressure level mean value recording for measuring surperficial all microphone positions place,
N is the number of measuring point.
4. as claimed in claim 1ly based on mean bias, determine the method that noise measuring point is arranged, it is characterized in that: described measurement surface is hemisphere measurement surface, the concrete method for arranging of measuring point is that position and the number of initial noise measuring point are arranged according to corresponding national standard or iso standard; When mean bias measured value is greater than mean bias threshold value, the geometric center of hemisphere projection on reflecting surface of take is initial point, and from initial point, on reflecting surface, drawing arbitrarily a straight line is x axle; Along x axle, be rotated counterclockwise 90 ° for y axle; Perpendicular to reflecting surface be z axle, initial noise measuring point be take to the measuring point that z axle obtains newly increasing as axis Rotate 180 °, original initial noise measuring point keeps former invariant position, the measuring point that position coincides is appointed and is got a bit.
5. as claimed in claim 1ly based on mean bias, determine the method that noise measuring point is arranged, it is characterized in that: described measurement surface is rectangular hexahedron measurement surface, the concrete method for arranging of measuring point is, according to the class of accuracy value of noise measurement, measuring distance d, size be than number k and the amplitude L that successively decreases, and arranges position and the number of initial noise measuring point according to corresponding national standard or iso standard; When mean bias measured value is greater than mean bias threshold value, the L of take successively reduces k value as amplitude, by measuring surface each face except bottom surface, be again separated into equidimension rectangular area unit and arrange measuring point, the measuring point that falls into bottom surface is cancelled, until mean bias measured value is less than or equal to mean bias threshold value.
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| CN106679797B (en) * | 2016-11-16 | 2021-04-23 | 中国电力科学研究院 | Method and device for testing sound insulation quantity of sound insulation cover of shunt reactor |
| CN107806928A (en) * | 2017-12-14 | 2018-03-16 | 中国西电电气股份有限公司 | A kind of device and method for testing power capacitor unit noise |
| CN111426377B (en) * | 2020-04-21 | 2021-01-22 | 国网四川省电力公司电力科学研究院 | Layout measurement system for multi-factory-boundary noise continuous monitoring device |
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| US4590579A (en) * | 1983-10-04 | 1986-05-20 | Ramsey Engineering Company | Apparatus and method for digital specific gravity measurement |
| US5574212A (en) * | 1995-06-14 | 1996-11-12 | Wisconsin Alumni Research Foundation | Automated system and method for testing resolution of ultrasound scanners |
| US5712805A (en) * | 1995-11-03 | 1998-01-27 | Wayne State University | Noise diagnostic system |
| CN101251412A (en) * | 2008-04-17 | 2008-08-27 | 上海交通大学 | Method for rebuilding circulation calm sound source by overlapping spherical wave |
| CN101922964A (en) * | 2010-05-27 | 2010-12-22 | 合肥工业大学 | Environmental noise monitoring device and method capable of distinguishing noise source direction |
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2013
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4590579A (en) * | 1983-10-04 | 1986-05-20 | Ramsey Engineering Company | Apparatus and method for digital specific gravity measurement |
| US5574212A (en) * | 1995-06-14 | 1996-11-12 | Wisconsin Alumni Research Foundation | Automated system and method for testing resolution of ultrasound scanners |
| US5712805A (en) * | 1995-11-03 | 1998-01-27 | Wayne State University | Noise diagnostic system |
| CN101251412A (en) * | 2008-04-17 | 2008-08-27 | 上海交通大学 | Method for rebuilding circulation calm sound source by overlapping spherical wave |
| CN101922964A (en) * | 2010-05-27 | 2010-12-22 | 合肥工业大学 | Environmental noise monitoring device and method capable of distinguishing noise source direction |
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