CN114992831A - Nozzle for an exhaust system and method for adjusting the speed of the nozzle - Google Patents
Nozzle for an exhaust system and method for adjusting the speed of the nozzle Download PDFInfo
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- CN114992831A CN114992831A CN202110229512.5A CN202110229512A CN114992831A CN 114992831 A CN114992831 A CN 114992831A CN 202110229512 A CN202110229512 A CN 202110229512A CN 114992831 A CN114992831 A CN 114992831A
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- 238000000034 method Methods 0.000 title claims abstract description 16
- 238000006073 displacement reaction Methods 0.000 claims description 34
- 238000001514 detection method Methods 0.000 claims description 13
- 238000005452 bending Methods 0.000 claims description 11
- 238000009792 diffusion process Methods 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 abstract description 5
- 230000003068 static effect Effects 0.000 description 10
- 238000001125 extrusion Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000012855 volatile organic compound Substances 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 230000001174 ascending effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005489 elastic deformation Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/08—Air-flow control members, e.g. louvres, grilles, flaps or guide plates
- F24F13/10—Air-flow control members, e.g. louvres, grilles, flaps or guide plates movable, e.g. dampers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
- F24F11/63—Electronic processing
- F24F11/64—Electronic processing using pre-stored data
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
- F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
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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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
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- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Signal Processing (AREA)
- Fluid Mechanics (AREA)
- Fuzzy Systems (AREA)
- Mathematical Physics (AREA)
- Air-Flow Control Members (AREA)
Abstract
The invention discloses a nozzle for an exhaust system and a method for adjusting the air speed of the nozzle. The nozzle is provided with an inner cylinder (1), an inner adjusting sheet (2), an outer adjusting sheet (3), a connecting rod (9), a connecting rod fixing support (13), an adjusting rod (10), a Venturi tube (5), a spring (6), a truncated cone (8) and an actuating mechanism (21). One end of each inner adjusting sheet and one end of each outer adjusting sheet are rotatably connected with the adjusting sheet hinged support (15), and the other ends of the adjacent inner adjusting sheets and the adjacent outer adjusting sheets are connected by the adjusting sheet connecting piece (4). On both sides of any one inner regulating sheet, the outer surface of each side is respectively contacted with the inner surface of one side of the adjacent outer regulating sheet and can slide relatively. The connecting rod is connected with an actuating mechanism driving arm (20) through a driving arm connecting piece (19). The invention also discloses a method for adjusting the air speed of the nozzle. The invention is mainly used for the variable air volume exhaust system of the petrochemical laboratory.
Description
Technical Field
The invention belongs to the technical field of ventilation air conditioners, relates to a nozzle for an exhaust system and a method for adjusting the air speed of the nozzle, and particularly relates to a nozzle for a variable air volume exhaust system of a petrochemical laboratory and a method for adjusting the air speed of the nozzle.
Background
At present, more and more petrochemical center laboratories adopt variable air volume exhaust systems. No matter in fan low frequency or high frequency operating condition, in order to maintain the wind speed in fan exit and satisfy the standard requirement, the conventional scheme adopts a special high altitude discharge fan in laboratory. The purposes of indoor variable air volume and fixed air volume at an air outlet are achieved by adjusting the opening of a bypass valve arranged at a suction inlet of the fan, and the air speed at the air outlet can be relatively and stably controlled within the range of 15-20 m/s. However, the fan adopts fixed-frequency operation, so that the later operation cost is high, and the vibration and noise are larger than those of a variable-frequency fan. When the variation range of the air exhaust amount is large, one scheme is that a mode that a plurality of variable frequency fans are connected in parallel is adopted to keep the air speed at the air outlet of the nozzle of the air exhaust system, and the opening degree of the air outlet of the nozzle is fixed. The frequency of the fan is adjusted through a static pressure sensor arranged at the tail end of the most unfavorable loop of the exhaust system, so that the static pressure in the air pipe is kept constant; and then the start and stop of the fan is controlled by a static pressure sensor arranged in the static pressure box at the inlet of the fan, and the opening of a bypass air valve is adjusted so as to maintain the static pressure in the static pressure box to be constant. When the bypass air valve is in a full-open state and the static pressure in the static pressure box exceeds a set maximum limit value, closing one fan; and when the bypass air valve is in a closed state and the static pressure in the static pressure box is lower than a set minimum limit value, starting a fan. Because the equipment quantity of this many fans parallel control mode is many, control is complicated, and its initial investment cost and later stage operation and maintenance cost are all than higher.
Disclosure of Invention
The invention aims to provide a nozzle for an exhaust system and a nozzle wind speed adjusting method, and aims to solve the problems of high cost, complex control and the like of the exhaust system caused by the fact that the existing exhaust system keeps the wind speed at the air outlet of the nozzle stable.
In order to solve the problems, the invention adopts the technical scheme that: a spout for an exhaust system, characterized in that: the inner barrel is provided with an inner barrel, inner adjusting pieces and outer adjusting pieces, wherein the inner adjusting pieces and the outer adjusting pieces are arranged at intervals, one end of each inner adjusting piece and one end of each outer adjusting piece are close to an air outlet of the inner barrel and are respectively rotatably connected with an adjusting piece hinged support, the other ends of the adjacent inner adjusting pieces and the adjacent outer adjusting pieces are connected by adjusting piece connecting pieces, the outer surface of each side of any one inner adjusting piece is respectively contacted with the inner surface of one side of the adjacent outer adjusting piece and can slide relatively, a connecting rod is arranged along the axial direction of the inner barrel and can move along the axial direction of the inner barrel, the inner barrel is provided with a Venturi tube, one end of the connecting rod adjacent to the air outlet of the inner barrel is provided with a connecting rod fixing support, the inner adjusting pieces and/or the outer adjusting pieces are provided with adjusting rod supports, an adjusting rod is arranged between the connecting rod fixing support and the adjusting rod supports, and the two ends of the adjusting rod are respectively rotatably connected with the connecting rod fixing support and the adjusting rod supports, a first fixing support is arranged between the Venturi tube and the connecting rod fixing support in the inner tube, a spring is arranged between the first fixing support and the connecting rod fixing support, a truncated cone is arranged in the diffusion section of the Venturi tube and fixed on the connecting rod, one end, adjacent to the air inlet of the inner tube, of the connecting rod is rotatably connected with one end of a driving arm connecting piece, and the other end of the driving arm connecting piece is rotatably connected with one end of a driving arm of the actuating mechanism.
A method for adjusting the nozzle air speed of a nozzle of an exhaust system is used for a variable air volume exhaust system and is characterized in that: the wind speed sensor in the wind speed detecting mechanism detects the wind speed of the wind pipe detected by the wind speed in the wind speed detecting mechanism and transmits the wind speed data to the controller, the controller calculates the air discharge quantity of the air exhaust system according to the wind speed and the cross-sectional area of the wind pipe detected by the wind speed, the controller calculates the expected value of the opening degree of the air outlet of the nozzle according to the air discharge quantity data of the air exhaust system and the expected value of the wind speed at the air outlet of the nozzle, then obtains the expected value of the angular displacement of the actuating arm of the actuating mechanism, compares the actual value of the angular displacement of the actuating arm of the actuating mechanism with the expected value, when the actual value of the angular displacement of the actuating arm of the actuating mechanism is smaller than or larger than the expected value of the angular displacement of the actuating arm of the actuating mechanism, the controller sends a regulating instruction to the actuating mechanism, the actuating mechanism regulates the angular displacement of the actuating arm of the actuating mechanism, and the actuating arm of the actuating mechanism drives the inner regulating piece and the outer regulating piece to rotate through the connecting rod mechanism, and when the actual value of the angular displacement of the actuating arm of the actuating mechanism is equal to the expected value of the angular displacement of the actuating arm of the actuating mechanism, the actual value of the opening of the air outlet of the nozzle is also equal to the expected value of the opening of the air outlet of the nozzle, and the air speed at the air outlet of the nozzle is adjusted to the expected value.
The invention has the following beneficial effects: (1) and the action of the nozzle is controlled by adopting a wind speed detection mechanism and a controller. The actuating mechanism drives the inner adjusting sheet and the outer adjusting sheet to rotate through the actuating arm of the actuating mechanism and the connecting rod mechanism, so that the opening degree of the air outlet of the nozzle and the air circulation area are enlarged or reduced, and the air speed at the air outlet of the nozzle is adjusted to a desired value. The operation process is simple, and the wind speed control precision is high. (2) The nozzle has simple structure and only one actuating mechanism. The air exhaust system only needs one fan, the requirement of constant air speed at the air outlet of the nozzle can be met without adopting a multi-fan parallel mode, and only one nozzle is needed, so that the control of the air exhaust system is simpler. (3) The air exhaust fan can continuously use the frequency conversion control to adjust the air exhaust volume of the air exhaust system, thereby achieving the purpose of energy conservation. By adopting the nozzle and the exhaust system (comprising the air speed adjusting device) using the nozzle, the initial investment cost, the later operation cost and the maintenance cost are lower.
The invention is mainly used for the variable air volume exhaust system of the petrochemical laboratory and can also be used for the variable air volume exhaust system of the laboratory in other fields.
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. The drawings and detailed description do not limit the scope of the invention as claimed.
Drawings
Fig. 1 is a schematic view of a nozzle for an exhaust system according to the present invention.
Fig. 2 is a schematic view of another embodiment of the nozzle of the present invention for use in an exhaust system.
FIG. 3 is an enlarged partial view of the ends of the inner and outer tabs with tab connectors provided.
FIG. 4 is an enlarged schematic cross-sectional view of the inner tab or the outer tab.
FIG. 5 is a schematic view of the wind speed adjustment apparatus of the present invention.
In fig. 1, the flap assembly, the inner cylinder, the outer cylinder and the venturi tube are partially cut away, and in fig. 2, the flap assembly, the inner cylinder and the venturi tube are partially cut away. In fig. 1 to 5, the same reference numerals denote the same technical features. The reference numerals denote: 1, an inner cylinder; 2-inner adjusting sheet; 3-external adjustment sheet; 4-tab connection; 5, a Venturi tube; 6-a spring; 7-a first fixed support; 8-a frustum; 81-the windward side of the frustum; 82-a truncated cone leeward side; 9-connecting rod; 10-adjusting the rod; 11-adjusting the lever support; 12-a second fixed support; 13-connecting rod fixing support; 14-a cylinder; 15-adjusting sheet hinged support; 16-an outer cylinder; 17-air inlet of inner cylinder; 18-nozzle air outlet; 19-a drive arm connection; 20-an actuator drive arm; 21-an actuator; 22-bending lines of the inner adjusting sheet 2 or the outer adjusting sheet 3; 23 — inventive spout; 24-outlet air pipe of the fan; 25-a fan; 26-inlet air pipe of blower; 27-wind speed detection means; 28-main air pipe of air exhaust system; 29-a controller; 30-control line.
Detailed Description
Referring to fig. 1, 2, 3 and 4, the nozzle (referred to as nozzle for short) for an exhaust system according to the present invention includes an inner cylinder 1, an inner adjusting piece 2, and an outer adjusting piece 3, wherein the inner adjusting piece 2 and the outer adjusting piece 3 are disposed at an interval and are disposed outside the inner cylinder 1. One end of each of the inner adjusting sheet 2 and the outer adjusting sheet 3 is close to the air outlet of the inner cylinder 1 and is respectively connected with an adjusting sheet hinged support 15 in a rotatable way (for example, hinged connection). The other ends of the adjacent inner adjusting sheets 2 and the adjacent outer adjusting sheets 3 are connected by an adjusting sheet connecting piece 4. On both sides of any one inner adjusting piece 2, the outer surface of each side is respectively contacted with the inner surface of one side of the adjacent outer adjusting piece 3 and can slide relatively. On both sides of any one outer adjusting blade 3, the inner surface of each side is respectively contacted with the outer surface of one side of the adjacent inner adjusting blade 2 and can slide relatively. All the inner adjusting sheets 2 and the outer adjusting sheets 3 form an adjusting sheet assembly, and the overall shape of the adjusting sheet assembly is approximately changed between a cylindrical shape (the opening degree of the nozzle air outlet 18 is the maximum) and a circular truncated cone side shape along with the inner adjusting sheets 2 and the outer adjusting sheets 3 rotating to different positions around the respective adjusting sheet hinged supports 15. The axial lead of the side surface shapes of the cylinder and the circular table is coaxial with the axial lead of the inner cylinder 1 to form the axial lead of the nozzle. One ends of the inner adjusting sheet 2 and the outer adjusting sheet 3, which are close to the air outlet of the inner barrel 1, are positioned at the outer side of the inner barrel 1, and the air outlet of the inner barrel 1 extends into the adjusting sheet assembly. The end heads of the inner adjusting sheet 2 and the outer adjusting sheet 3, which are provided with the end parts of the adjusting sheet connecting pieces 4, enclose a nozzle air outlet 18.
The nozzle is provided with a connecting rod 9 along the axial direction of the inner cylinder 1, and the connecting rod 9 can move along the axial direction of the inner cylinder 1; the connecting rod 9 is generally located on the axis of the spout. The inner cylinder 1 is coaxially provided with a Venturi tube 5, the Venturi tube 5 consists of a contraction section, a throat and a diffusion section, and the Venturi tube 5 is arranged from an air inlet 17 of the inner cylinder to an air outlet of the inner cylinder 1. A connecting rod fixing support 13 is fixed at one end of the connecting rod 9 adjacent to the air outlet of the inner cylinder 1, and the other end of the connecting rod 9 is adjacent to the air inlet 17 of the inner cylinder.
An adjusting rod support 11 is fixed on a part or all of the inner adjusting sheets 2 and/or the outer adjusting sheets 3, an adjusting rod 10 is arranged between the connecting rod fixing support 13 and the adjusting rod support 11, and two ends of the adjusting rod 10 are respectively rotatably connected with the connecting rod fixing support 13 and the adjusting rod support 11. The adjusting rod supports 11 and the adjusting rods 10 are generally arranged at least 3 respectively; the maximum number of the inner adjusting blades 2 and the outer adjusting blades 3 is the same as the total number of the inner adjusting blades 2 and the outer adjusting blades 3, i.e., one adjusting rod support 11 and one adjusting rod 10 are provided for one inner adjusting blade 2 or one outer adjusting blade 3. The adjusting rods 10 are evenly distributed around the axial lead of the nozzle. As shown in fig. 1 and 2, several outer adjusting plates 3 are fixed with adjusting rod holders 11.
A first fixing bracket 7 is arranged between the Venturi tube 5 and the connecting rod fixing support 13 in the inner cylinder 1, and the first fixing bracket 7 is fixed on the inner cylinder 1. The first fixing bracket 7 is provided with a spring seat and a central hole in the center, a spring 6 is arranged between the spring seat and the connecting rod fixing support 13, and the connecting rod 9 penetrates through the central hole and the spring 6. The spring 6 may be a cylindrical coil spring, a conical coil spring, or the like, in a compressed state. The nozzle of the invention is generally vertically arranged, and the air outlet 18 of the nozzle faces upwards. Part of the weight of the connecting rod 9, the truncated cone 8, the connecting rod fixing support 13, the adjusting rod 10, the adjusting rod support 11, the inner adjusting sheet 2 and the outer adjusting sheet 3 is borne by the spring 6, and the spring 6 transmits the weight and the weight to the first fixing support 7, so that the stress of the actuating arm 20 of the actuating mechanism and the corner torque output of the actuating arm can be reduced. The above-mentioned truncated cone 8 is arranged in the diverging section of the venturi tube 5, the truncated cone 8 being fixed to a connecting rod 9.
One end of the connecting rod 9 adjacent to the inner cylinder air inlet 17 is rotatably connected with one end of a driving arm connecting piece 19, the other end of the driving arm connecting piece 19 is rotatably connected with one end of an actuating mechanism driving arm 20, and the other end of the actuating mechanism driving arm 20 is connected with a driving component in an actuating mechanism 21. The actuator arm 20 extends through an opening in the inner barrel 1.
The inner adjusting sheet 2 and the outer adjusting sheet 3 are generally herringbone sheet plates, the cross section of the inner adjusting sheet is herringbone, and the inner adjusting sheet is unfolded into a plane and is rectangular or trapezoidal. Fig. 4 shows the cross-sectional shape of the inner adjusting plate 2 or the outer adjusting plate 3, the bending angle V and the bending line 22. The bending angle V of the inner adjusting sheet 2 and the outer adjusting sheet 3 is generally 120-160 degrees, and the thickness is generally 0.5-2 mm. The inner adjusting piece 2 and the outer adjusting piece 3 are generally arranged 3-9 respectively, and the number of the inner adjusting piece and the outer adjusting piece is the same.
Referring to fig. 3 and also to fig. 1 and 2, an adapter piece 4 for the spout according to the invention is a strip-shaped plate with a strip-shaped hole. In the adjacent inner and outer tabs 2 and 3, one end of a tab connecting member 4 is fixed to the outer surface of one side of the inner tab 2, and a cylinder 14 is fixed to the outer surface of one side of the outer tab 3 adjacent to one side of the inner tab 2. Alternatively, one end of the tab connecting member 4 is fixed to the outer surface of the outer tab 3, and a cylinder 14 (not shown) is fixed to the outer surface of the inner tab 2 adjacent to the outer tab 3. Alternatively, one end of the tab connecting member 4 is fixed to the inner surface of the inner tab 2, and a cylinder 14 (not shown) is fixed to the inner surface of the outer tab 3 adjacent to the inner tab 2. Alternatively, one end of the tab connecting member 4 is fixed to the inner surface of the outer tab 3 side, and a cylinder 14 (not shown) is fixed to the inner surface of the inner tab 2 side adjacent to the outer tab 3 side. In various arrangements, the post 14 is inserted into a slot in the tab connector 4, and during rotation of the inner tab 2 and the outer tab 3 about the tab hinge support 15, the post 14 can slide relative to the slot (mainly along the length of the slot). In the width direction of bar hole, need leave certain clearance between cylinder 14 and the bar hole, do not hinder between interior adjustment flap 2 and the outer adjustment flap 3 in the ascending relative slip of bar hole width direction. The end of the cylinder 14 is provided with a stopper (e.g., a pin) to prevent the cylinder 14 from being separated from the strip hole. The pillars 14 are generally cylindrical or prismatic.
In one embodiment of the nozzle of the present invention, the flap hinge support 15 has a fixed shaft, and the fixed shaft is covered with an outer sleeve which can rotate around the fixed shaft. The end parts of the bending lines of the inner adjusting sheet 2 and the outer adjusting sheet 3 are fixedly connected (for example, welded) with the outer sleeve at one end of the inner adjusting sheet 2 and the outer adjusting sheet 3 which are rotatably connected with the adjusting sheet hinge support 15.
The frustum 8 is generally a body of revolution or a truncated pyramid, the centre line of which coincides with the axis of the connecting rod 9, with two bases perpendicular to the axis of the spout. The bottom surface close to the throat outlet of the Venturi tube 5 is a frustum windward surface 81, the other bottom surface is a frustum leeward surface 82, and the area of the frustum leeward surface 82 is larger than that of the frustum windward surface 81. The cross-sectional area of the frustum 8 increases progressively from the throat of the venturi 5 to the outlet of the diffuser section. When the truncated cone 8 is a rotating body, the generatrix on the side surface can be a straight line or an arc line and the like; when the generatrix is a straight line, the truncated cone 8 has a truncated cone shape (i.e., a truncated cone shape).
Usually, a second fixing bracket 12 is also arranged between the venturi tube 5 and the inner cylinder air inlet 17 in the inner cylinder 1, and the second fixing bracket 12 is fixed on the inner cylinder 1. The second fixing bracket 12 has a central hole in the center through which the connecting rod 9 passes.
As shown in fig. 2, the flap hinge support 15 is fixed to the inner cylinder 1. As shown in fig. 1, an outer cylinder 16 may be provided around the inner cylinder 1 outside the inner cylinder 1, the outer cylinder 16 is fixed to the inner cylinder 1 (not shown) using a conventional method and means, and the flap hinge support 15 is fixed to the outer cylinder 16. When the adjusting sheet hinged support 15 is fixed on the inner cylinder 1 or the outer cylinder 16, a reinforcing structure (not shown) can be arranged at the fixed position. The inner cylinder 1 is cylindrical except for the venturi tube 5, and the outer cylinder 16 is cylindrical. The inner barrel 1 and the outer barrel 16 are generally coaxially disposed. The opening degree of the spout outlet 18 shown in fig. 1 is in an expanded state, and the opening degree of the spout outlet 18 shown in fig. 2 is in a contracted state. The nozzle orifice shown in fig. 1 is identical to the nozzle orifice shown in fig. 2 in other parts not illustrated.
The material of each component of the nozzle is generally selected from stainless steel, galvanized steel, aluminum alloy and other corrosion-resistant and non-metallic materials with certain strength. The materials of the inner adjusting sheet 2, the outer adjusting sheet 3 and the adjusting sheet connecting piece 4 also have certain elastic deformation capacity. Lubricating oil and lubricating grease can be added between the components which move relatively.
The air exhaust system can form a new air speed adjusting device by using the nozzle. Referring to fig. 5, the wind speed adjusting device includes the nozzle 23 of the present invention, a controller 29, a wind speed detecting mechanism 27, and the like. The air inlet 17 of the inner cylinder of the nozzle 23 is connected with the outlet of an air exhaust system fan 25 or the outlet of an air pipe 24 at the outlet of the fan, the inlet of the fan 25 is connected with the outlet of an air speed detection mechanism 27 through an air pipe 26 at the inlet of the fan, and the inlet of the air speed detection mechanism 27 is connected with the outlet of a main air pipe 28 of the air exhaust system. The wind speed detection mechanism 27 is composed of an existing wind speed sensor and a wind speed detection wind pipe; the cross-sectional area of the wind speed detection duct is known, calculated according to the inner diameter of the wind speed detection duct, and is built in the controller 29 in advance. The wind speed sensor may be an existing pitot tube type wind speed sensor, a propeller type wind speed sensor, an ultrasonic type wind speed sensor, or the like. The fan 25 is a conventional variable frequency fan, and the controller 29 controls the rotation speed and the delivery air volume of the fan 25 through a control line 30. The controller 29 is connected with the actuator 21, the fan 25 and the wind speed detecting mechanism 27 of the nozzle 23 of the present invention through control lines 30. The controller 29 may use a conventional programmable controller (PLC), a Direct Digital Controller (DDC), or the like, and the actuator 21 may use a conventional electric, pneumatic, or hydraulic actuator.
The connecting rod 9, the connecting rod fixing support 13, the adjusting rod 10, the adjusting rod support 11, the spring 6, the frustum 8, the driving arm connecting piece 19 and other components form a connecting rod mechanism. Through the link mechanism, the one-to-one correspondence and accurate relationship between the actual value of the opening degree of the nozzle outlet 18 and the actual value of the angular displacement of the actuator driving arm 20 and between the expected value of the opening degree of the nozzle outlet 18 and the expected value of the angular displacement of the actuator driving arm 20 can be respectively established. The expected value according to the present invention is a value to which an actual value is expected.
When the exhaust system exhausts, the exhaust volume changes (increases or decreases). The wind speed adjusting device shown in fig. 5 operates, and the wind speed sensor in the wind speed detecting means 27 detects the wind speed in the wind speed detecting duct and transmits the wind speed data to the controller 29 through the control line 30, and the controller 29 calculates the discharge air volume of the discharge system based on the wind speed and the cross-sectional area of the wind speed detecting duct. The controller 29 calculates the expected value of the opening of the outlet 18 of the nozzle according to the air discharge data of the exhaust system and the expected value of the wind speed at the outlet 18 of the nozzle, obtains the expected value of the angular displacement of the actuating arm 20 of the actuating mechanism, and compares the actual value of the angular displacement of the actuating arm 20 of the actuating mechanism with the expected value. The actuator 21 transmits the actual value of the angular displacement of the actuator drive arm 20 to the controller 29 via control line 30. The following wind speed adjusting process will be described by taking the nozzle shown in the drawing of the present invention as an example.
When the actual value of the angular displacement of the actuator driving arm 20 is smaller than the expected value of the angular displacement of the actuator driving arm 20, the actual value of the opening degree of the spout air outlet 18 is smaller than the expected value of the opening degree of the spout air outlet 18, and the actual wind speed value at the spout air outlet 18 is larger than the expected value. At this time, the controller 29 sends an adjustment instruction to the actuator 21 through the control line 30, the actuator 21 adjusts the angular displacement of the actuator driving arm 20 to increase the angular displacement, the actuator driving arm 20 drives the connecting rod 9 to move in a direction close to the nozzle outlet 18 through the driving arm connecting member 19, and the connecting rod fixing support 13 and the truncated cone 8 move along with the connecting rod 9. The adjusting rod 10 moves along with the connecting rod fixing support 13, and two ends of the adjusting rod 10 respectively rotate relative to the connecting rod fixing support 13 and the adjusting rod support 11, so as to push the outer adjusting sheet 3 provided with the adjusting rod support 11 to rotate around the respective adjusting sheet hinged support 15. The outer adjusting piece 3 sequentially drives the inner adjusting piece 2 and other outer adjusting pieces 3 which are not provided with the adjusting rod support 11 to rotate around the respective adjusting piece hinged supports 15 through the contact and extrusion between the outer surface of the side part of the inner adjusting piece 2 and the inner surface of the side part of the outer adjusting piece 3 through the adjusting piece connecting piece 4. The end parts of the inner adjusting sheet 2 and the outer adjusting sheet 3, which are provided with the adjusting sheet connecting pieces 4, move in the direction away from the axial lead of the nozzle, so that the opening of the air outlet 18 of the nozzle is enlarged. When the actual value of the angular displacement of the actuator driving arm 20 is equal to the expected value of the angular displacement of the actuator driving arm 20, the actual value of the opening degree of the nozzle air outlet 18 is also equal to the expected value of the opening degree of the nozzle air outlet 18, and the air speed at the nozzle air outlet 18 is adjusted to the expected value.
When the actual value of the angular displacement of the actuator driving arm 20 is greater than the expected value of the angular displacement of the actuator driving arm 20, the actual value of the opening of the spout air outlet 18 is greater than the expected value of the opening of the spout air outlet 18, and the actual wind speed value at the spout air outlet 18 is less than the expected value. At this time, the controller 29 sends an adjustment instruction to the actuator 21 through the control line 30, the actuator 21 adjusts the angular displacement of the actuator driving arm 20 to reduce the angular displacement, the actuator driving arm 20 drives the connecting rod 9 to move in a direction away from the spout outlet 18 through the driving arm connecting member 19, and the connecting rod fixing support 13 and the truncated cone 8 move along with the connecting rod 9. The adjusting rod 10 moves along with the connecting rod fixing support 13, and two ends of the adjusting rod 10 respectively rotate relative to the connecting rod fixing support 13 and the adjusting rod support 11, so as to pull the outer adjusting sheet 3 provided with the adjusting rod support 11 to rotate around the respective adjusting sheet hinged support 15. The outer adjusting piece 3 drives the inner adjusting piece 2 and other outer adjusting pieces 3 without the adjusting rod support 11 to rotate around the respective adjusting piece hinged supports 15 through the contact and extrusion between the inner surface of the side part of the outer adjusting piece 3 and the outer surface of the side part of the inner adjusting piece 2 and the adjusting piece connecting piece 4. The end parts of the inner adjusting sheet 2 and the outer adjusting sheet 3, which are provided with the adjusting sheet connecting pieces 4, move towards the direction close to the axial lead of the nozzle, so that the opening degree of the air outlet 18 of the nozzle is reduced. When the actual value of the angular displacement of the actuator driving arm 20 is equal to the expected value of the angular displacement of the actuator driving arm 20, the actual value of the opening degree of the nozzle outlet 18 is also equal to the expected value of the opening degree of the nozzle outlet 18, and the wind speed at the nozzle outlet 18 is adjusted to the expected value.
In the above operation process, the air in the main air duct 28 of the exhaust system enters the blower 25 through the air speed detection mechanism 27 and the blower inlet air duct 26, then enters the inner barrel 1 through the blower outlet air duct 24 or the outlet of the blower 25, and finally is exhausted from the nozzle air outlet 18. In fig. 1, 2, and 5, the arrow without reference sign indicates the flow direction of the gas (wind). For a variable air volume exhaust system of a petrochemical laboratory, the exhausted gas is generally a mixed gas of corrosive gas containing Volatile Organic Compounds (VOCs) and air.
The expected value of the wind speed at the air outlet 18 of the nozzle is generally 15-20 m/s. Other expected wind speed values can also be set according to the actual engineering requirements.
Under the condition that all the inner adjusting sheets 2 and the outer adjusting sheets 3 are fixed with adjusting rod supports 11, an adjusting rod 10 is respectively arranged corresponding to each inner adjusting sheet 2 and each outer adjusting sheet 3, and the adjusting rods 10 directly drive each inner adjusting sheet 2 and each outer adjusting sheet 3 to rotate around the adjusting sheet hinged support 15. Under the condition that adjusting rod supports 11 are fixed on part of the inner adjusting sheets 2 and the outer adjusting sheets 3, an adjusting rod 10 is respectively arranged corresponding to each inner adjusting sheet 2 and each outer adjusting sheet 3, and the adjusting rods 10 directly drive each inner adjusting sheet 2 and each outer adjusting sheet 3 to rotate around the adjusting sheet hinged support 15; the inner adjusting sheet 2 and the outer adjusting sheet 3 sequentially drive other inner adjusting sheets 2 and other outer adjusting sheets 3 which are not provided with the adjusting rod support 11 to rotate around the respective adjusting sheet hinged supports 15 through the contact and extrusion between the adjusting sheet connecting piece 4 and the outer surface of the side part of the inner adjusting sheet 2 and the inner surface of the side part of the outer adjusting sheet 3.
When the exhaust air volume of the exhaust system is increased, the air volume entering the inner cylinder 1 is increased, the air speed in the throat and at the outlet of the throat of the Venturi tube 5 is increased, and the air thrust on the windward side 81 of the truncated cone is increased. When the connecting rod 9 moves towards the direction close to the nozzle outlet 18, the thrust is beneficial to reducing the corner torque output of the actuating arm 20 of the actuating mechanism to the connecting rod 9. Under the condition that the nozzle is vertically arranged and the nozzle air outlet 18 is upwards arranged, when the air exhaust volume of the exhaust system is reduced, the air volume entering the inner cylinder 1 is reduced, the air speeds in the throat and at the outlet of the throat of the Venturi tube 5 are reduced, and the air thrust on the windward side 81 of the truncated cone is reduced. When the connecting rod 9 moves in a direction away from the nozzle outlet 18 (i.e. moves downwards), the partial weights of the connecting rod 9, the frustum 8, the connecting rod fixing support 13, the adjusting rod 10, the adjusting rod support 11, the inner adjusting sheet 2 and the outer adjusting sheet 3 can offset the effect of reduced gas thrust on the windward side 81 of the frustum, and the corner torque output of the actuating arm 20 of the actuating mechanism to the connecting rod 9 is not greatly increased.
A certain gap is formed between one end of the inner adjusting sheet 2 and the outer adjusting sheet 3, which are close to the air outlet of the inner barrel 1, and the outer surface of the inner barrel 1. In the above-mentioned air exhausting process, the air outside the nozzle of the present invention is sucked into the nozzle through the gap, mixed with the air inside the nozzle, and then ejected from the nozzle outlet 18. Some gaps exist at the contact part of the outer surface of the side part of the inner adjusting sheet 2 and the inner surface of the side part of the outer adjusting sheet 3, air leakage is small and can be ignored.
When the inner adjusting piece 2 and the outer adjusting piece 3 rotate, each bending line 22 rotates in a plane passing through the bending line 22 and the axial line of the nozzle. Each adjustment lever 10 is generally rotatable and movable in a plane passing through the axis of the adjustment lever 10 and the nozzle. The actuator drive arm 20 typically oscillates about its end connected to the drive member of the actuator 21, generally in a plane passing through the actuator drive arm 20 and the axis of the nozzle. When swinging, one end of the actuating mechanism driving arm 20 connected with the driving arm connecting piece 19 is close to or away from the nozzle air outlet 18; when approaching the spout outlet 18, the angular displacement of the actuator arm 20 increases; upon exiting the spout outlet 18, the actuator arm 20 is less angularly displaced. An appropriate datum may be selected to determine the angular displacement of the actuator drive arm 20. For example, a straight line extending from a point on the actuator driving arm 20 in a direction away from the nozzle outlet 18 and parallel to the nozzle axis is selected, and a portion of the actuator driving arm 20 between the point on the actuator driving arm 20 and the end of the actuator driving arm 20 connected to the driving arm connecting member 19 is selected, and an included angle between the portion and the straight line is used as the angular displacement a of the actuator driving arm 20 (as shown in fig. 1).
For the nozzles with different structural parameters and the wind speed detection mechanism 27 with known cross-sectional areas of the wind speed detection pipes, according to the description of the specification, by performing limited calculation and experiments, a relation curve between the opening degree of the nozzle air outlet 18 and the air discharge amount of the exhaust system and the angular displacement of the actuating arm 20 of the actuating mechanism can be obtained in advance, and the data of the curve is embedded in the controller 29. For the controller 29, a person skilled in the art can easily perform programming, data setting, connection of control lines 30, etc. to achieve the required control of the wind speed adjusting process of the present invention to keep the wind speed at the outlet 18 of the nozzle within a desired range. The detailed description is omitted.
The method for adjusting the air speed of the nozzle is not limited to the nozzle. The nozzle proposed according to the inventive concept, which is similar in structure and working principle to the nozzle according to the invention, can also be used in the inventive method.
Claims (9)
1. A nozzle for an exhaust system, comprising: the air conditioner is provided with an inner barrel (1), inner adjusting sheets (2) and outer adjusting sheets (3), wherein the inner adjusting sheets (2) and the outer adjusting sheets (3) are arranged at intervals, one end of each inner adjusting sheet (2) and one end of each outer adjusting sheet (3) are close to an air outlet of the inner barrel (1) and are respectively rotatably connected with an adjusting sheet hinged support (15), the other ends of the adjacent inner adjusting sheets (2) and the adjacent outer adjusting sheets (3) are connected through adjusting sheet connecting pieces (4), the outer surface of each side is respectively contacted with the inner surface of one side of the adjacent outer adjusting sheet (3) and can slide relatively, a connecting rod (9) is arranged along the axial direction of the inner barrel (1), the connecting rod (9) can move along the axial direction of the inner barrel (1), the inner barrel (1) is provided with a Venturi tube (5), one end of the connecting rod (9) adjacent to the air outlet of the inner barrel (1) is provided with a connecting rod fixed support (13), an adjusting rod support (11) is arranged on the inner adjusting sheet (2) and/or the outer adjusting sheet (3), an adjusting rod (10) is arranged between the connecting rod fixing support (13) and the adjusting rod support (11), two ends of the adjusting rod (10) are respectively rotatably connected with the connecting rod fixing support (13) and the adjusting rod support (11), a first fixing support (7) is arranged between the Venturi tube (5) and the connecting rod fixing support (13) in the inner cylinder (1), a spring (6) is arranged between the first fixing support (7) and the connecting rod fixing support (13), a truncated cone (8) is arranged in a diffusion section of the Venturi tube (5), the truncated cone (8) is fixed on the connecting rod (9), one end, adjacent to an air inlet (17) of the inner cylinder, of the connecting rod (9) is rotatably connected with one end of a driving arm connecting piece (19), and the other end of the driving arm connecting piece (19) is rotatably connected with one end of an actuating mechanism driving arm (20).
2. The spout of claim 1, wherein: inner control flap (2) and outer control flap (3) are the font slab, and control flap connecting piece (4) are the lath, have the bar hole, in adjacent inner control flap (2) and outer control flap (3), the one end of control flap connecting piece (4) is fixed on the surface of inner control flap (2) one side, with be fixed with cylinder (14) on the surface of inner control flap (2) one side adjacent outer control flap (3) one side, perhaps, the one end of control flap connecting piece (4) is fixed on the surface of outer control flap (3) one side, with be fixed with cylinder (14) on the surface of outer control flap (3) one side adjacent inner control flap (2) one side, perhaps, the one end of control flap connecting piece (4) is fixed on the internal surface of inner control flap (2) one side, with be fixed with cylinder (14) on the internal surface of inner control flap (2) one side adjacent outer control flap (3) one side, or one end of the adjusting sheet connecting piece (4) is fixed on the inner surface of one side of the outer adjusting sheet (3), a column body (14) is fixed on the inner surface of one side of the inner adjusting sheet (2) adjacent to one side of the outer adjusting sheet (3), and the column body (14) is inserted into the strip-shaped hole in the adjusting sheet connecting piece (4) and can slide relative to the strip-shaped hole.
3. The spout of claim 2, wherein: the adjusting sheet hinged support (15) is provided with a fixed shaft, an outer sleeve is sleeved outside the fixed shaft, the outer sleeve can rotate around the fixed shaft, the end of a bending line of the inner adjusting sheet (2) and the outer adjusting sheet (3) is fixedly connected with the outer sleeve at one end of the adjusting sheet hinged support (15), and the end of the bending line of the inner adjusting sheet (2) and the end of the bending line of the outer adjusting sheet (3) are fixedly connected with the outer sleeve.
4. A spout according to claim 2 or 3, wherein: the angle V of bending of interior adjustment piece (2) and outer adjustment piece (3) is 120 ~ 160 degrees, and thickness is 0.5 ~ 2 millimeters, and interior adjustment piece (2) and outer adjustment piece (3) respectively set up 3 ~ 9, and the quantity is the same.
5. A spout according to claim 1 or 2, wherein: the frustum (8) is a rotary body or a truncated pyramid, and the cross section area of the frustum (8) is gradually increased from the throat of the Venturi tube (5) to the outlet of the diffusion section.
6. A spout according to claim 1, 2 or 3, wherein: a second fixed bracket (12) is arranged between the Venturi tube (5) and the inner cylinder air inlet (17) in the inner cylinder (1).
7. A spout according to claim 1, 2 or 3, wherein: the adjusting sheet hinge support (15) is fixed on the inner cylinder (1).
8. A spout according to claim 1, 2 or 3, wherein: an outer cylinder (16) is arranged around the inner cylinder (1) outside the inner cylinder (1), and the adjusting sheet hinged support (15) is fixed on the outer cylinder (16).
9. A method for adjusting the air speed of a nozzle is used for an air exhaust system with variable air volume and is characterized in that: an air speed sensor in the air speed detection mechanism (27) detects the air speed of an air pipe detected by the air speed in the air speed detection mechanism (27), the air speed data is transmitted to a controller (29), the controller (29) calculates the air discharge quantity of an exhaust system according to the air speed and the cross section area of the air pipe detected by the air speed, the controller (29) calculates the expected value of the opening degree of the nozzle air outlet (18) according to the air discharge quantity data of the exhaust system and the expected value of the air speed at the nozzle air outlet (18), and then obtains the expected value of the angular displacement of the actuating arm (20) of the actuating mechanism and compares the expected value. When the actual value of the angular displacement of the actuating mechanism driving arm (20) is smaller than or larger than the expected value of the angular displacement of the actuating mechanism driving arm (20), the controller (29) sends an adjusting instruction to the actuating mechanism (21), the actuating mechanism (21) adjusts the angular displacement of the actuating mechanism driving arm (20), the actuating mechanism driving arm (20) drives the inner adjusting sheet (2) and the outer adjusting sheet (3) to rotate through the connecting rod mechanism, the opening degree of the nozzle air outlet (18) is enlarged or reduced, when the actual value of the angular displacement of the actuating mechanism driving arm (20) is equal to the expected value of the angular displacement of the actuating mechanism driving arm 20, the actual value of the opening degree of the nozzle air outlet (18) is also equal to the expected value of the opening degree of the nozzle air outlet (18), and the air speed at the nozzle air outlet (18) is adjusted to the expected value.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110229512.5A CN114992831B (en) | 2021-03-02 | 2021-03-02 | Nozzle for exhaust system and nozzle wind speed adjusting method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110229512.5A CN114992831B (en) | 2021-03-02 | 2021-03-02 | Nozzle for exhaust system and nozzle wind speed adjusting method |
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| CN114992831B CN114992831B (en) | 2024-02-09 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203476605U (en) * | 2013-09-06 | 2014-03-12 | 国电联合动力技术有限公司 | Wind generating set with stall regulation function |
| CN204790514U (en) * | 2015-08-13 | 2015-11-18 | 珠海昊星自动化系统有限公司 | Intelligent coordinated control system of venturi fume chamber |
| CN106194235A (en) * | 2016-09-09 | 2016-12-07 | 西安科技大学 | Manual type colliery tunneling ventilation air duct air outlet regulation device |
| CN107401421A (en) * | 2017-09-16 | 2017-11-28 | 西安科技大学 | Colliery tunneling ventilation air duct air outlet regulation device based on PLC controls |
| CN111535937A (en) * | 2020-05-29 | 2020-08-14 | 山东理工大学 | Aviation three-dimensional vector engine tail nozzle |
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2021
- 2021-03-02 CN CN202110229512.5A patent/CN114992831B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203476605U (en) * | 2013-09-06 | 2014-03-12 | 国电联合动力技术有限公司 | Wind generating set with stall regulation function |
| CN204790514U (en) * | 2015-08-13 | 2015-11-18 | 珠海昊星自动化系统有限公司 | Intelligent coordinated control system of venturi fume chamber |
| CN106194235A (en) * | 2016-09-09 | 2016-12-07 | 西安科技大学 | Manual type colliery tunneling ventilation air duct air outlet regulation device |
| CN107401421A (en) * | 2017-09-16 | 2017-11-28 | 西安科技大学 | Colliery tunneling ventilation air duct air outlet regulation device based on PLC controls |
| CN111535937A (en) * | 2020-05-29 | 2020-08-14 | 山东理工大学 | Aviation three-dimensional vector engine tail nozzle |
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| CN114992831B (en) | 2024-02-09 |
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