CN106841672B - Array winglet detection boiler secondary device and method for dividing wind speed of wind channel - Google Patents
Array winglet detection boiler secondary device and method for dividing wind speed of wind channel Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/14—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring differences of pressure in the fluid
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
Abstract
The invention discloses a method and a device for detecting the wind speed of a secondary air distribution channel of a boiler by an array small wing speed measuring tube, which comprises the following steps: the method comprises the steps of dividing a straight section on a secondary air dividing duct with a rectangular section into a plurality of small air ducts with rectangular equal sections by utilizing a rectifying and derotation device, arranging a small wing speed measuring tube array, and simultaneously measuring each small air duct to obtain the wind speed in the secondary air dividing duct, wherein the length of each small air duct in the airflow flowing direction is at least 0.8d, and d is the equivalent diameter of the small air duct. The method for reducing the section length and the section width of the flow channel further reduces the straight section length of the flow channel required by the small wing speed measuring tube, so that the small wing speed measuring tube can be suitable for measuring the speed in a secondary air distribution channel with a short straight section and an SOFA over-fire air distribution channel, thereby obtaining the accurate wind speed of the nozzle, enabling the air inlet ratio of the boiler to be more accurate, facilitating the combustion, optimizing the air distribution adjustment and reducing the generation of NOx gas.
Description
Technical Field
The invention relates to the field of air duct detection of boilers, in particular to a device and a method for detecting the wind speed of secondary air branch air ducts and overfire air branch air ducts of power station boilers and industrial boilers.
Background
At present, in industrial production, particularly in power station boilers or industrial boiler equipment, some large-scale air channels and short straight sections of the flue still have no effective means for more accurate measurement, some large-section low-flow-rate occasions also have no means for more accurate measurement, and the conditions of variable sections, turning and reversing of the flow channels, changeable flow fields, uneven flow rates, extremely short straight sections or no straight sections can not be measured. The most of secondary air separation channels and burnout channels of a power station boiler or an industrial boiler are short in straight section, and the secondary air separation channels refer to single small air channels from the tail end of a secondary air large bellows and the rear of a secondary air small air door to each secondary air nozzle. As shown in the accompanying drawings 1, 2 and 3, the straight section is extremely short, and the turning direction and the variable cross section are adopted; as shown in figure 4 of the drawings, is a typical "C" type air duct; even if the air duct has no straight section, multiple turning reversing and changeable flow field, as shown in fig. 5, the air duct is a typical S-shaped air duct, the flow passage section is continuously changed, and the prior art means cannot detect in real time. The secondary air of the boiler is combustion-supporting air in the furnace, the secondary air in the main combustion area is main secondary air, and the secondary air in the burnout area is burnout sofa secondary air, which is also called burnout air. The organization of the combustion process in the furnace and the reasonable allocation of the secondary air and the over-fire air are very important, and directly influence the combustion efficiency and the generation of harmful emissions.
The cold state opening characteristic calibration can be only carried out on the secondary air dividing door by the prior art, the wind speed and the wind quantity can be roughly judged by the opening of the air door, and even some boilers can judge the secondary air proportion only according to the static pressure change of the secondary air box at each angle. Because the traditional differential pressure method for detecting the wind speed of the wind channel requires longer front and rear straight sections of a measuring point, taking a pitot tube, a flute pipe and a backrest pipe as examples, the front straight section of the measuring point is larger than 6-8D (equivalent diameter), and the rear straight section of the measuring point is larger than 2-3D. The shapes of the secondary air distribution channels of different boilers are also different, and the requirements of the secondary air distribution channels are greatly different from those of the traditional measurement. The current situation of secondary wind separation detection obviously cannot realize more accurate adjustment and more cannot realize accurate adjustment, so that difficulties and barriers are brought to optimization of boiler combustion, emission of ultralow harmful substances, improvement of production level and reduction of cost. The technology disclosed in patent application number 201511000798.0 only shows that the small wing sensor can be applied to Reynolds number Re=2×10 of air flow in an air duct of a utility boiler 5 -9.8×10 5 Is the region of lower reynolds number. Although the elliptical head small section airfoil type speed measuring tube can be regarded as the development of the modern differential pressure type flow velocity measuring technology; however, the detection technology method with great difficulty like secondary air distribution channels of power station boilers and industrial boilers is not solved.
Disclosure of Invention
Because of the characteristics of the small wing speed measuring tube, the straight section L1 at the upstream of the small wing is more than or equal to 0.6d (d is equivalent diameter), and the straight section L2 at the downstream of the small wing is more than or equal to 0.2d, so that the measurement accuracy can be ensured. The requirements of the small wings on the measurement straight section are greatly reduced compared with the traditional differential pressure method measurement, and the aim of the invention is how to further reduce the requirements on the measurement straight section so as to realize the wind speed detection of the secondary air distribution channel of the boiler.
Aiming at the problems existing in the prior art, one of the purposes of the invention is to provide a method for detecting the wind speed of a secondary air distribution channel of a boiler by using an array small wing speed measuring tube.
The technical scheme of the invention is as follows:
the method for detecting the wind speed of the secondary air distribution channel of the boiler by using the array winglet comprises the following steps: the straight section on the secondary air separation channel with the rectangular section is divided into a plurality of small air channels with the rectangular section by utilizing the rectifying and despin device, the length of the small air channels in the airflow flowing direction is at least 0.8d, d is the equivalent diameter of the small air channels, and the small wing speed measuring tube array is arranged on the rectifying and despin device, so that each small air channel is measured simultaneously, and the wind speed in the secondary air separation channel is obtained.
Further, the method comprises the following specific steps: step 1, selecting a straight section on a secondary air dividing duct, and dividing the section of the air duct into a plurality of rectangular small air ducts with equal cross sections by using a rectifying and unscrewing device;
step 2, arranging an array small wing speed measuring tube on the rectifying and derotation device, so that the small wing speed measuring tube can measure the total pressure and the static pressure in each small air duct, wherein the distance between the small wing speed measuring tube and the upstream end of the small air duct is at least 0.6d, and the distance between the small wing speed measuring tube and the downstream end of the small air duct is at least 0.2d;
and step 3, calculating the wind speed in the secondary air dividing duct through the measured full pressure value and the static pressure value.
Further, the rectifying and derotation device is a grid structure formed by a plurality of thin steel plates, and the thickness of the thin steel plates is as thin as possible.
Further, in the step 2, the rectifying and despin device divides the secondary air-dividing duct into N in section length a The equal parts of the components are arranged in the same way, divided into N in its cross-sectional width b Equal parts, the winglet speed measuring tube is arranged in the secondary air distribution channel along the length direction of the section or the width direction of the section, and penetrates through the whole secondary air distribution channel.
Further, the small wing speed measuring tube is connected with a micro differential pressure meter through a pressure transmission tube, and the wind speed in the secondary air dividing channel is calculated through the micro differential pressure.
Further, when a plurality of the winglet tachometer pipes are used for measurement, the winglet tachometer pipe array is arranged and connected with the same pressure transmission pipe.
Further, the flow resistance of the rectifying and despin device to the airflow is lower than 100 Pa-120 Pa.
Further, the method is also applied to an overfire air distribution duct.
The device for detecting the wind speed of the secondary air distribution channel of the boiler by using the array winglet speed measuring tube is used for realizing the method, and comprises the following steps:
the rectifying and unscrewing device is arranged at the straight section of the secondary air dividing channel with the rectangular section and is used for dividing the air dividing channel into a plurality of small air channels with rectangular uniform sections, the length of the small air channels in the airflow flowing direction is at least 0.8d, and d is the equivalent diameter of the small air channels;
the small wing speed measuring tube is inserted in the small air duct, is at least 0.6d away from the upstream end of the small air duct and at least 0.2d away from the downstream end of the small air duct, and is used for detecting the total pressure and the static pressure of the small air duct so as to obtain the wind speed in the secondary air dividing duct.
Further, the small wing wind speed detection apparatus includes: the small wing speed measuring tube is used for measuring total pressure and static pressure in the air duct, the small wing speed measuring tube is inserted from the side wall of the secondary air dividing duct, and the pressure transmitting tube is connected with the small wing speed measuring tube and the micro differential pressure meter.
Further, the rectifying and derotation device is a grid structure formed by a plurality of thin steel plates, and the thickness of the thin steel plates is as thin as possible.
Further, the secondary air distribution channel is replaced by an overfire air distribution channel.
According to the calculation formula d=2a×b/(a+b) of the equivalent diameter of the rectangular flow channel, the equivalent diameter d is related to the section length a of the flow channel and the section width b of the flow channel, so that the method for reducing the section length and the section width of the flow channel is utilized to further reduce the straight line length of the flow channel required by the small wing speed measuring tube, so that the small wing speed measuring tube can be suitable for measuring the speed in the secondary air distribution channel and the over-fire air distribution channel with very short straight sections, the accurate wind speed of a nozzle is obtained, the air inlet proportion of the boiler is more accurate, and the combustion efficiency of the boiler is improved.
The array winglet measuring method and the array winglet measuring technology can realize real-time online accurate detection of wind speeds of the secondary air distribution channel and the overfire air secondary air distribution channel of the main combustion area of the power station boiler, are convenient for the boiler to realize combustion optimization air distribution adjustment and reduce NOx generation.
The small flow channels can weaken vortex rotation of air flow, so that uniformity of fluid is improved, and accuracy of measurement is facilitated.
And the full-section measuring point is formed, so that the accuracy, the representativeness and the reliability of measurement are ensured, and the method is easy to implement.
Drawings
FIG. 1 is a schematic plan view of a secondary air separation duct of a boiler of a certain 350MW generator set;
FIG. 2 is a schematic plan view of a sofa air-dividing duct of a certain 350MW generator set boiler;
FIG. 3 is a schematic plan view of a sofa air-dividing duct of a boiler of a certain 600MW generator set;
FIG. 4 is a schematic plan view of a secondary air separation duct of a 330MW generator set boiler;
FIG. 5 is a schematic plan view of a secondary air separation duct of a 600MW generator set boiler;
FIG. 6 is a schematic cross-sectional view of a device for detecting the wind speed of a secondary air separation duct of a boiler by using an array winglet;
FIG. 7 is a schematic view of the front and rear straight sections of the small flow channels of the device for detecting the wind speed of the secondary air distribution channel of the boiler by the array small wings;
FIG. 8 is a schematic diagram of a layout of a small wing of a secondary split duct array of a certain 350MW generator set boiler;
FIG. 9 is a schematic diagram of a layout of a small wing of a sofa over-fire split duct array of a certain 350MW generator set boiler;
FIG. 10 is a schematic diagram of a 600MW genset boiler sofa burnout split duct array winglet arrangement;
FIG. 11 shows a 330MW power generation set boiler secondary a small wing arrangement schematic diagram of the air-splitting duct array;
FIG. 12 is a schematic diagram of a 600MW genset boiler secondary air separation duct array winglet arrangement;
in the figure, a secondary air separation channel 1, a rectifying and unscrewing device 2, a 3-wing speed measuring tube, a 31 full pressure tube, a 32 static pressure tube, a 4 pressure transmitting tube and a 5 micro differential pressure meter are arranged.
Detailed Description
The present invention will be described more fully with reference to the following examples. This invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein.
Spatially relative terms, such as "upper," "lower," "left," "right," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature's illustrated in the figures. It will be understood that the spatial terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "under" other elements or features would then be oriented "over" the other elements or features. Thus, the exemplary term "lower" may encompass both an upper and lower orientation. The device may be otherwise positioned (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The device for detecting the wind speed of the secondary air distribution channel of the boiler by using the array winglet shown in fig. 6 and 7 comprises: the rectifying and derotation device 2 is a grid structure formed by a plurality of thin steel plates, the rectifying and derotation device 2 is arranged in a straight section of the secondary air separation channel 1 with a rectangular section to divide the secondary air separation channel 1 into a plurality of small air channel rectifying and derotation devices with rectangular uniform sections, namely, each grid in the rectifying and derotation device 2 forms an independent small air channel. The thickness of the thin steel plate rectifying and despin device constituting the rectifying and despin device should be as thin as possible to avoid unnecessary increase of the flow resistance of the rectifying and despin device 2. The rectifying and despin device 2 has two functions, namely, rectifying and despin functions, so that vortex is reduced, the wind speed in a small flow channel is uniform, and accurate measurement is facilitated; another effect is that the measuring straight section can be further shortened so that it is extremely short. Therefore, the small wing speed measuring tube 3 can measure the wind speed of the secondary air dividing duct of various variable forms of the boiler.
The structure of the rectifying and derotation device 2 refers to figure 6, and the length A of the section of the air duct is divided into n a Equally dividing the width B of the air duct section into n b Aliquoting to form a plurality of n i Small channels with length a=a/n a Wide b=b/n a The method comprises the steps of carrying out a first treatment on the surface of the Each small channel is provided with a group of measuring points, and the equivalent diameter of the channel with a small rectangular section is as follows:
equivalent diameter of the whole air duct measurement section
Compared with D < D, the method can be reduced by more than 3 times until the aim is achieved.
In this embodiment, the rectifying and dissipating device 2 divides the secondary air separation channel 1 into 8 small air channels, and of course, the secondary air separation channel 1 can be divided into more or less small air channels, the smaller the equivalent diameter of the small air channels is, the shorter the measured straight length is, but the flow resistance of the rectifying device is increased along with the increase of the number of small channels, and the larger the flow resistance of the secondary air separation channel is, the larger the momentum loss of the fluid is; in order to achieve accurate measurement without excessively increasing the flow resistance, the number of small channels is designed appropriately so that the flow resistance of the rectifying device is lower than 100 Pa-120 Pa. The section of the small air duct is still rectangular, the length of the small air duct in the airflow flowing direction is at least 0.8d, and d is the equivalent diameter of the small air duct; the winglet wind speed detection apparatus includes: the structure and the use method of the small wing speed measuring tube 3, the pressure transmission tube 4 and the micro differential pressure meter 5 are described in detail in the Chinese patent application with the patent application number 201511000798.0, the small wing speed measuring tube 3 is internally provided with a full pressure tube 31 capable of detecting the full pressure in the air duct and a static pressure tube 32 capable of detecting the static pressure in the air duct, the small wing speed measuring tube 3 is inserted from the side wall of the secondary air separation duct 1 and is inserted into the four small air ducts for detection, therefore, the two small wing speed measuring tubes 3 are required to be equipped to complete simultaneous detection of 8 small air ducts, the distance between the small wing speed measuring tube 3 and the upstream end of the small air duct is at least 0.6d, the distance between the small wing speed measuring tube 3 and the downstream end of the small air duct is at least 0.2d, the two small wing speed measuring tubes 3 are connected with the pressure transmission tube 4, the pressure transmission tube 4 is connected with the micro differential pressure meter 5, and the wind speed in the secondary air separation duct 1 is calculated according to the measured full pressure value and the static pressure value. When more small wing speed measuring tubes 3 are needed to be equipped, the small wing speed measuring tubes 3 are arranged according to an array. Of course, the secondary air distribution duct 1 can be replaced by an over-fire air distribution duct, so that the device can be applied in the over-fire air distribution duct.
The method for detecting the wind speed of the secondary air distribution channel of the boiler by using the array winglet speed measuring tube comprises the following specific steps:
step 1, selecting a straight section on a secondary air separation channel 1, and separating the section of air separation channel into a plurality of small air channels with rectangular cross sections by utilizing a rectifying and unscrewing device 2, wherein the length of the small air channels in the airflow flowing direction is at least 0.8d, and d is the equivalent diameter of the small air channels;
step 2, inserting an array of small wing speed measuring pipes 3 into the secondary air dividing duct 1 where the rectifying and dissipating device 2 is located, so that the small wing speed measuring pipes 3 can measure the total pressure and the static pressure in each small air dividing duct, wherein the distance between the small wing speed measuring pipes 3 and the upstream end of the small air dividing duct is at least 0.6d, and the distance between the small wing speed measuring pipes 3 and the downstream end is at least 0.2d;
and 3, connecting the small wing speed measuring tube 3 with a micro differential pressure meter 5 through a pressure transmission tube 4, and calculating the wind speed in the secondary air dividing duct 1 according to the measured total pressure value and the measured static pressure value.
Preferably, in step 2, the rectifying and despin device 2 divides the secondary air dividing duct 1 into N in section length a Equal parts divided into N in cross-sectional width b Equal parts, the winglet speed measuring tube 3 is arranged in the secondary air distribution channel 1 along the length direction of the section or the width direction of the section and penetrates through the whole secondary air distribution channel 1.
The secondary air separation duct 1 can be replaced by an over-fire air separation duct, so that the method is applied to the over-fire air separation duct.
Example 1
FIG. 8 shows a secondary air distribution duct of a 350MW generator set boiler, wherein the secondary air distribution duct is arranged in a main combustion area of the boiler, and a straight section behind a small air door of the secondary air distribution duct is shorter and is led to a secondary air nozzle next to a right-angle elbow. For the array winglet measurement technique, the short straight section before the right angle elbow and after the small throttle has met the conditions. The small wing speed measuring pipes are horizontally arranged, the wing heads face to the incoming flow, 2 small wing speed measuring pipes 3 are arranged in parallel in the vertical direction in each air dividing duct, a rectifying and rotation dissipating device 2 is arranged, 8-16 small channels are formed on the measuring section, the system also has 8-16 corresponding groups of measuring points, meets the requirements of the wing type speed measuring tube on the relevant straight section, can transmit accurate differential pressure signals to the micro differential pressure meter through the pressure transmitting tube, and measures the flow speed, the flow and the nozzle wind speed of the air duct.
Example 2
Fig. 9 shows that a certain 350MW generator set boiler sofa burn-out air distribution duct, unlike the primary and secondary air distribution ducts described above, a small damper of the air distribution duct is followed by a straight section that is not long and is followed by an elbow of about 120 ° leading to the nozzle. The measurement purpose can be achieved by adopting the technical method.
Example 3
Fig. 10 shows a 600MW genset boiler sofa burnout split duct, no straight duct after small damper, the measuring purpose can be realized by using the straight section air duct position in front of the small air door and adopting the technical method as above by using the array small wing measuring technology.
Example 4
FIG. 11 shows a secondary air distribution duct of a 330MW generator set boiler, which is a secondary air distribution duct of a four-corner tangential combustion boiler and is arranged in a secondary air large bellows at two sides of the boiler, and the secondary air distribution duct is turned and then led to a connected secondary air nozzle, and is a typical C-shaped air duct. Meanwhile, the flow cross section of the air duct is continuously changed in the turning process, and the wind speed and the wind quantity cannot be accurately measured by the traditional measuring means or other methods. Under the condition, according to the specific structural characteristics of the air duct, the rectifying and derotation device is additionally arranged at the position of the extremely short straight section, the small wing speed measuring tube 3 is horizontally arranged, the wing head faces to the incoming flow, 2-3 small wing speed measuring tubes 3 are arranged in parallel in the vertical direction in each sub-air duct, 12-18 small channels are formed on the measuring section by utilizing the rectifying and derotation device 2, the corresponding 12-18 groups of measuring points are also arranged, the rectifying and derotation device 2 divides the air duct into a plurality of small rectangular section flow channels, and the straight section lengths of the front and the rear of the small wing measuring points are ensured to meet the measuring requirements in each small flow channel. The rectifying and unscrewing device 2 can be reasonably and skillfully matched with the guide plate in the air duct, and the detecting device can be used for transmitting accurate differential pressure signals to the micro differential pressure meter through the pressure transmission pipe. Therefore, the wind speed and the wind quantity passing through the rectifying device can be accurately measured by using the array winglet detection technology, and the accurate wind speed of the secondary wind nozzle can be further obtained.
Example 5
FIG. 12 shows a secondary air distribution duct of a 600MW generator set boiler, which is arranged in a wall-type tangential circle combustion mode, and the secondary air distribution duct formed by a large bellows is close to an S-shaped air distribution duct, and is not provided with a very short straight section. As shown in the figure, the structural characteristics of the air duct can be partially modified to create a very short straight section, and the rectifying and unscrewing device can be additionally arranged. Similarly, the small wing speed measuring pipes are horizontally arranged horizontally, the wing heads face to the incoming flow, and 2-3 small wing speed measuring pipes 3 are arranged in parallel in the vertical direction in each air dividing duct. When the rectifying and derotation device 2 is configured, 12-18 small rectangular cross-section flow passages are formed on the measuring section, and the flow passages also have corresponding 12-18 groups of measuring points, so that the requirements of the wing-shaped speed measuring tube on the relevant straight sections are met. And the rectifying device can be reasonably and skillfully matched with the guide plate in the air duct, the measuring device can transmit accurate differential pressure signals to the micro differential pressure meter through the pressure transmission pipe, the flow speed and the flow of the air duct are measured, and the aim of accurately measuring the wind speed of the secondary air nozzle is fulfilled.
The above examples are for illustration of the invention only and, in addition, there are many different embodiments which will be apparent to those skilled in the art after having the insight into the present invention and are not explicitly recited herein.
Claims (9)
1. The method for detecting the wind speed of the secondary air distribution channel of the boiler by the array winglet is characterized by comprising the following steps: dividing a straight section on a secondary air dividing duct with a rectangular section into a plurality of small air ducts with rectangular sections by using a rectifying and despin device, wherein the length of each small air duct in the airflow flowing direction is at least 0.8d, d is the equivalent diameter of the small air duct, and a small wing speed measuring pipe is arranged on the rectifying and despin device to realize simultaneous measurement of each small air duct so as to obtain the wind speed in the secondary air dividing duct;
the method comprises the following specific steps: step 1, selecting a straight section on a secondary air dividing duct, and dividing the section of the air duct into a plurality of rectangular small air ducts with equal cross sections by using a rectifying and unscrewing device;
step 2, arranging an array small wing speed measuring tube on the rectifying and derotation device, so that the small wing speed measuring tube can measure the total pressure and the static pressure in each small air duct, wherein the distance between the small wing speed measuring tube and the upstream end of the small air duct is at least 0.6d, and the distance between the small wing speed measuring tube and the downstream end of the small air duct is at least 0.2d;
step 3, calculating the wind speed in the secondary air dividing duct through the measured full pressure value and the static pressure value;
in the step 2, the rectifying and despin device divides the length A of the secondary air dividing duct on the section length into N a Equal parts, width B in its cross-sectional width is divided into N b Equal parts, form n i Small channels with length a=a/n a Wide b=b/n b The method comprises the steps of carrying out a first treatment on the surface of the The small wing speed measuring tube is arranged in the secondary air dividing duct along the length direction of the section or the width direction of the section and penetrates through the whole secondary air dividing duct;
each small channel is provided with a group of measuring points, and the equivalent diameter of the channel with a small rectangular section is as follows:the equivalent diameter of the whole air duct measurement section is as follows: />The flow resistance of the rectifying and despin device to the airflow is lower than 100 Pa-120 Pa.
2. The method of claim 1, wherein the rectifying and despin device is a grid structure formed of a plurality of thin steel plates.
3. The method of claim 1, wherein the winglet velocimeter is connected to a micro-differential pressure gauge through a pressure transfer tube, and the wind speed in the secondary air distribution duct is calculated from the micro-differential pressure.
4. A method according to claim 3, wherein an array of winglets is arranged and interconnected with the same pressure transmitting tube when measured using a plurality of winglets.
5. The method of claim 1, further applied to an overfire air distribution duct.
6. An apparatus for detecting the wind speed of a secondary air distribution duct of a boiler by using an array winglet, which is characterized in that the apparatus is used for realizing the method of any one of the claims 1-4, and the apparatus comprises:
the rectifying and unscrewing device is arranged at the straight section of the secondary air dividing channel with the rectangular section and is used for dividing the air dividing channel into a plurality of small air channels with rectangular uniform sections, the length of the small air channels in the airflow flowing direction is at least 0.8d, and d is the equivalent diameter of the small air channels;
the small wing wind speed pipe is inserted in the small air duct, is at least 0.6d away from the upstream end of the small air duct and at least 0.2d away from the downstream end of the small air duct, and is used for detecting the total pressure and the static pressure of the small air duct so as to obtain the wind speed in the secondary air separation duct.
7. The apparatus of claim 6, wherein the winglet wind speed detection device comprises: the small wing speed measuring tube is used for measuring total pressure and static pressure in the air duct, the small wing speed measuring tube is inserted from the side wall of the secondary air dividing duct, and the pressure transmitting tube is connected with the small wing speed measuring tube and the micro differential pressure meter.
8. The apparatus of claim 6, wherein said rectifying and despin means is a grid structure formed of a plurality of thin steel plates.
9. The apparatus of claim 6, wherein the secondary air distribution duct is replaced with an overfire air distribution duct.
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| CN201710041942.8A CN106841672B (en) | 2017-01-20 | 2017-01-20 | Array winglet detection boiler secondary device and method for dividing wind speed of wind channel |
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| CN201710041942.8A CN106841672B (en) | 2017-01-20 | 2017-01-20 | Array winglet detection boiler secondary device and method for dividing wind speed of wind channel |
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| CN105628969A (en) * | 2015-12-28 | 2016-06-01 | 北京博希格动力技术有限公司 | Small section streamline body airfoil-shaped wind velocity sensor |
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- 2017-01-20 CN CN201710041942.8A patent/CN106841672B/en active Active
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| CN1392391A (en) * | 2002-07-25 | 2003-01-22 | 浙江大学 | Multiple air channel air amount measuring method and device in large air channel |
| CN201464488U (en) * | 2009-07-02 | 2010-05-12 | 杭州意能节能技术有限公司 | Honeycomb air duct flow-equalizing speed testing device |
| CN201654053U (en) * | 2010-03-19 | 2010-11-24 | 艾佩克斯科技(北京)有限公司 | Wind-speed online monitoring device of large-section air duct |
| JP2011232316A (en) * | 2010-04-23 | 2011-11-17 | Shibata Giken Co Ltd | Honeycomb and air duct incorporating the same |
| CN203535068U (en) * | 2013-06-20 | 2014-04-09 | 国家电网公司 | Measuring device for wind speed and wind volume based on static pressure principle |
| CN204854832U (en) * | 2015-05-15 | 2015-12-09 | 康鹏 | Multiple spot is got and is pressed amount of wind measuring device based on grid racemization principle |
| CN105628969A (en) * | 2015-12-28 | 2016-06-01 | 北京博希格动力技术有限公司 | Small section streamline body airfoil-shaped wind velocity sensor |
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| CN106841672A (en) | 2017-06-13 |
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