CN211233299U - Air duct of air conditioner with lower air supply - Google Patents
Air duct of air conditioner with lower air supply Download PDFInfo
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- CN211233299U CN211233299U CN201922353031.6U CN201922353031U CN211233299U CN 211233299 U CN211233299 U CN 211233299U CN 201922353031 U CN201922353031 U CN 201922353031U CN 211233299 U CN211233299 U CN 211233299U
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Abstract
The utility model discloses a lower air supply air conditioner air duct, which comprises an air duct main body and an air quantity detection device arranged in the air duct main body; air volume detection device includes the venturi nozzle, locates preceding cowling panel before the venturi nozzle with locate back cowling panel behind the venturi nozzle, the venturi nozzle with set up preceding static pressure sensor between the preceding cowling panel, the throat of venturi nozzle is equipped with back static pressure sensor, preceding static pressure sensor with back static pressure sensor connects differential pressure transmitter, differential pressure transmitter is used for the basis preceding static pressure sensor with the pressure differential calculation air supply flow that back static pressure sensor detected. The air duct of the lower air supply air conditioner can accurately monitor the air supply flow of the precision air conditioner, and the insufficient cooling of a machine room is avoided.
Description
Technical Field
The utility model relates to an air conditioning equipment ventilation field, in particular to air conditioner wind channel of supplying air down.
Background
The inter-column precise air conditioner of the medium and large data center belongs to a redundancy design, and only part of the precise air conditioners operate most of the time. If the standby air conditioner is close to the running air conditioner, cold air flows back outwards through a gap of a fan of the standby air conditioner under the action of static pressure, and the leakage of the air supply amount is caused. In addition, the leaked cold air is mixed with return air of an operating air conditioner, so that the problems of cold short circuit, insufficient cooling of machine room loads and the like can be caused.
In a conventional data center, the inter-row precise air conditioner generally adopts a downward-feeding and upward-returning airflow organization mode, that is, the flow direction of cold air is as follows: the system comprises a precise air-conditioning fan, an overhead floor, a perforated air supply floor, a cold channel and a cooled IT device. When the precision air conditioner operates, because the air speed at the outlet of the fan is not uniform, a vortex area can be formed in a flow field, and the dynamic pressure of cold air is prevented from being converted into uniform static pressure, so that IT equipment in a machine room cannot be effectively cooled, and the phenomenon of local overheating is caused.
With the development of air conditioning technology, precise refrigeration is more and more emphasized. At present, the technology capable of accurately monitoring the precise air supply quantity of the data center on line is not mature. Because of the influence of factors such as frequency converter power factor and fan mechanical characteristics, the fan flow model obtained by using the conversion of the rotating speed has larger error with the real flow and lower air quantity monitoring accuracy.
Therefore, how to accurately detect the cooling air volume and improve the cooling efficiency of the cooled IT equipment becomes a technical problem to be solved by the technical personnel in the field.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a lower air supply air conditioner wind channel, this air conditioner wind channel can accurate monitoring precision air conditioner supply air flow, avoids the computer lab cooling not enough.
In order to achieve the purpose, the utility model provides a lower air supply air conditioner air duct, which comprises an air duct main body and an air quantity detection device arranged in the air duct main body; air volume detection device includes the venturi nozzle, locates preceding cowling panel before the venturi nozzle with locate back cowling panel behind the venturi nozzle, the venturi nozzle with set up preceding static pressure sensor between the preceding cowling panel, the throat of venturi nozzle is equipped with back static pressure sensor, preceding static pressure sensor with back static pressure sensor connects differential pressure transmitter, differential pressure transmitter is used for the basis preceding static pressure sensor with the pressure differential calculation air supply flow that back static pressure sensor detected.
Optionally, preceding cowling panel with back cowling panel all includes the circular orifice plate of equidistant setting, and is adjacent the ventilation hole of circular orifice plate sets up relatively.
Optionally, the differential pressure transmitter is connected with a precision air conditioner controller;
and when the air supply flow deviates from the preset value, the precision air conditioner controller is used for controlling the precision air conditioner to adjust the air supply flow.
Optionally, the air duct main body is provided with an arc-shaped air inlet cavity for connecting an air outlet of a precision air conditioner, and the air outlet of the air duct main body is connected with the raised floor plenum box.
Optionally, preceding cowling panel with the alternate setting of venturi nozzle, back cowling panel with the air outlet laminating setting of venturi nozzle.
Optionally, the venturi nozzle includes a truncated cone-shaped inlet convergent section, an outlet divergent section, and a cylindrical throat section connecting the inlet convergent section and the outlet divergent section, and the back static pressure sensor is disposed in the throat section.
Optionally, a self-hanging louver is further arranged in the air duct main body;
the self-hanging shutter comprises an outer frame, rotating shafts which are rotatably connected with the outer frame and are arranged in parallel, and blades which are fixedly connected with the rotating shafts in a one-to-one correspondence mode.
Optionally, a gasket is disposed between the outer frame and the inner wall of the air duct main body.
Optionally, an insulating layer is arranged on the inner wall of the air duct main body.
Optionally, the diameter of a pressure taking hole for installing the front static pressure sensor and the rear static pressure sensor is 0.5-1.0 mm, and the axis of the pressure taking hole is perpendicular to the axis of the air duct main body.
Compared with the prior art, the utility model provides a lower air supply air conditioner wind channel includes the wind channel main part and sets up the amount of wind detection device in the wind channel main part, this amount of wind detection device includes preceding cowling panel, back cowling panel and the venturi nozzle of setting between preceding cowling panel and back cowling panel, utilize preceding cowling panel and back cowling panel to carry out the rectification to the air supply, the homogeneity of control air current, be convenient for detect the air supply flow, static pressure sensor before setting up between venturi nozzle and preceding cowling panel, static pressure sensor after the throat of venturi nozzle sets up, utilize the differential pressure transmitter who is connected with preceding static pressure sensor and back static pressure sensor to calculate the air supply flow according to the pressure differential that records, thereby make things convenient for accurate monitoring air supply flow, control air conditioner air supply, maintain computer lab equipment temperature.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic view of a lower air supply air conditioning duct provided in an embodiment of the present invention;
FIG. 2 is a schematic view of the airway body of FIG. 1;
FIG. 3 is a schematic view of the self-hanging blind of FIG. 1;
FIG. 4 is a schematic view of the venturi nozzle and aft fairing of FIG. 1.
Wherein:
01-precision air conditioner, 1-precision air conditioner controller, 2-air duct main body, 3-self-hanging shutter, 4-front rectifying plate, 5-Venturi nozzle, 6-rear rectifying plate, 7-front static pressure sensor, 8-rear static pressure sensor and 9-differential pressure transmitter.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In order to make the technical field of the present invention better understand, the present invention will be described in detail with reference to the accompanying drawings and the detailed description.
Referring to fig. 1 to 4, fig. 1 is a schematic view of a lower blowing air conditioning duct according to an embodiment of the present invention, fig. 2 is a schematic view of a duct body in fig. 1, fig. 3 is a schematic view of a self-hanging louver in fig. 1, and fig. 4 is a schematic view of a venturi nozzle and a rear rectifying plate in fig. 1; note that the direction of the arrow in fig. 1 indicates the air blowing direction.
The utility model provides a lower air supply air conditioner wind channel includes wind channel main part 2 and sets up in wind channel main part 2, is used for detecting and monitoring the amount of wind detection device of air supply flow. In order to realize the accurate detection to air supply flow in the wind channel main part 2, be equipped with preceding cowling panel 4 and back cowling panel 6 in the wind channel main part 2, through the air current in preceding cowling panel 4 and the stable and even wind channel of back cowling panel 6, be convenient for improve the accurate nature that the static pressure detected. And for the tradition obtain the air supply flow inaccuracy and receive factors influence such as air leakage through converter power conversion, the utility model discloses a set up venturi nozzle 5 between preceding cowling panel 4 and back cowling panel 6, utilize the air supply to calculate the air supply flow through the change of pressure and velocity of flow when venturi nozzle 5, the air supply flow in the wind channel main part 2 of acquireing that can be accurate to in the cooling demand adjustment air supply flow according to the computer lab, avoid the computer lab load cooling to be not enough or surplus.
The present invention provides a lower air supply air conditioning duct, which will be described in more detail with reference to the accompanying drawings and specific embodiments.
In a specific embodiment provided by the present invention, please refer to fig. 1 and 2, a front section of the air duct main body 2 is an arc-shaped air inlet cavity, and an air inlet of the arc-shaped air inlet cavity is disposed upward and is used for being connected with an air outlet of the precision air conditioner 01 and receiving downward air supply of the precision air conditioner 01; the rear section of the air duct main body 2 extends horizontally, and an air outlet of the rear section is used for being connected with the overhead bottom plate static pressure box; after cooling air flows out from the fan impeller of the precision air conditioner 01, the cooling air can be conveyed to the rear section of the air duct main body 2 extending horizontally after being converged and transited by the arc-shaped air inlet cavity of the air duct main body 2, and a good air supply effect is obtained. The air quantity detection device is arranged in the rear section of the air duct main body 2 extending horizontally.
Wherein, the cross-section of the horizontal extending back end of the air duct main body 2 can be set to be rectangular, the front fairing 4 and the back fairing 6 are embedded on the inner wall of the air duct main body 2, and the venturi nozzle 5 is arranged between the front fairing 4 and the back fairing 6. The front static pressure sensor 7 is arranged between the venturi nozzle 5 and the front fairing plate 4, and a space for mounting the front static pressure sensor 7 needs to be reserved between the front fairing plate 4 and the venturi nozzle 5, so that the front fairing plate 4 and the venturi nozzle 5 are arranged in parallel at a certain interval, the rear static pressure sensor 8 is arranged at the throat part of the venturi nozzle 5, the venturi nozzle 5 is also called a convergent-divergent nozzle, and the throat part refers to a transition section from the convergent-divergent nozzle aperture to the convergent-divergent nozzle aperture.
The front rectifying plate 4 and the rear rectifying plate 6 play a role in rectifying cooling air, uniform air flow can be formed, the cross section size of the air duct main body 2 is usually large, pressure detection points cannot cover all positions, and the rectification through the front rectifying plate 4 and the rear rectifying plate 6 forms uniform air flow to ensure the accuracy of pressure measurement of the front static pressure sensor 7 and the rear static pressure sensor 8, so that the accuracy of flow detection is improved. And in the installation, need install preceding cowling panel 4 earlier usually, in order to improve the convenience of installation, back cowling panel 6 and the laminating of venturi nozzle 5 set up as an organic whole, and convenient the fixing.
The front rectifying plate 4 and the rear rectifying plate 6 both adopt circular pore plates, for example, the front rectifying plate 4 comprises two circular pore plates which are arranged in parallel, and the vent holes formed on the circular pore plates are equal in size and are in one-to-one correspondence in position; the rear fairing 6 is identical in structure and size to the front fairing 4. In other words, the distance between the circular hole plates of the two circular hole plates is also equal. The round orifice plate is a plate with a round hole, the front rectifying plate 4 and the rear rectifying plate 6 can be arranged to comprise two groups of round orifice plates or more groups of round orifice plates as required, and the adjacent round orifice plates are usually kept parallel and arranged at equal intervals.
When the standby air conditioner is close to the running air conditioner, cooling air flows backwards outwards through a gap of a fan of the standby air conditioner under the action of static pressure, and air supply quantity is leaked. In order to avoid the backflow of the cooling air, in another embodiment of the present invention, a self-hanging louver 3 for preventing the backflow of the cooling air is further disposed in the air duct main body 2.
Referring to fig. 4, the venturi nozzle 5 includes a truncated cone-shaped inlet convergent section and an outlet divergent section, the inlet convergent section and the outlet divergent section are disposed opposite to each other at one end with a smaller diameter and are connected by a cylindrical throat section to form a structure with a constricted-transitional-divergent diameter, so as to change the flow rate and pressure of the supplied air. The back static pressure sensor 8 is arranged in the throat section. Generally speaking, the venturi nozzles are arranged in a plurality of groups, and the plurality of groups are fixed as a whole and installed in the air duct main body 2, and are attached to the rear rectifying plate 6 through the outlet expanding section.
Referring to fig. 1 and 3, the self-drooping louver 3 is disposed in front of the front rectifying plate 4, so that the front rectifying plate 4 can rectify the airflow disturbed by the louver; the self-hanging shutter 3 comprises an outer frame, wherein the outer frame is in a shape matched with the air duct main body 2, the outer frame is rotatably connected with a plurality of rotating shafts which are arranged in parallel in the outer frame, any one of the rotating shafts is fixedly connected with a blade, and the blade is eccentrically connected with the rotating shafts, so that the blade can be closed under the action of self weight, and the air duct main body 2 connected with a standby air conditioner cannot leak cooling air; when the precise air conditioner operates, the self-hanging shutter 3 can be opened under the pushing of the wind pressure of cooling wind, and the air is supplied to the air quantity detection device in the air duct main body 2.
In order to further improve the sealing performance of the air duct main body 2 and prevent air leakage, a sealing gasket is arranged between the outer frame of the self-hanging shutter 3 and the inner wall of the air duct main body 2, and the phenomena of air return and air leakage are reduced through the arrangement of the sealing gasket.
Generally speaking, the inner wall of the air duct main body 2 is also provided with a heat insulation layer in a fitting manner, so that the heat convection between the cooling air in the air duct main body 2 and the machine room bottom plate is reduced, and the loss of the cooling capacity (the cooling capacity of the machine room equipment) of the cooling air in the air duct main body 2 is inhibited.
The pressure is obtained by the front static pressure sensor 7 and the rear static pressure sensor 8 and then is transmitted to the differential pressure transmitter 9, and the air supply flow can be calculated by the differential pressure transmitter 9 according to the measured differential pressure and the specification of the venturi nozzle 5.
The differential pressure transmitter 9 calculates the flow rate from the differential pressure by the following formula:
wherein:
Qnthe actual air supply flow is;
n is the number of the Venturi nozzles 5;
Anthe throat area of the venturi nozzle 5;
delta p is the difference value of the pressures measured by the front static pressure sensor 7 and the rear static pressure sensor 8;
ρ is the air density (the air density at room temperature can be taken, and more precisely the air density corresponding to the cooling air temperature in the air duct main body 2);
and C is the discharge coefficient of the nozzle.
The calculation and monitoring of the air supply flow can be completed by pre-storing the preset calculation program and parameters in the differential pressure transmitter 9, and a display component can be arranged to be connected with the differential pressure transmitter 9 to display the air supply flow in real time. In order to improve the measurement accuracy, a plurality of sets of front static pressure sensors 7 and rear static pressure sensors 8 can be provided, and the detection accuracy can be improved by calculating the average value of the measured pressure differences.
Further, the axis of the pressure taking hole for installing the front static pressure sensor 7 and the rear static pressure sensor 8 is perpendicular to the incoming flow direction, that is, the axis of the pressure taking hole is perpendicular to the axis of the rear section of the air duct main body 2. When the edge of the pressure taking hole is provided with burrs or is uneven, local eddy current can be generated, so that certain deviation is generated in measurement. In order to improve the measurement accuracy, the edge of the pressure tapping hole needs to be machined smoothly.
The pressure taking hole is formed in the inner wall of the air duct main body 2 and the side wall of the throat section of the Venturi nozzle 5, when air supply flows through, fluid in the hole is disturbed under the action of viscous shear stress, and a streamline close to the position of the pressure taking hole is bent towards the inside of the hole, so that static pressure in the normal direction in the boundary layer is changed, and the measured static pressure value deviates from the true value. Under certain velocity of flow, when the aperture of pressure taking hole is great, the degree of curvature of streamline can grow, leads to the measuring error of static pressure great. Therefore, in order to improve the measurement accuracy of the static pressure and take practical engineering application into consideration, the diameter of the pressure measuring hole is usually set within the range of 0.5-1.0 mm.
Furthermore, in order to adjust the air supply quantity of the precision air conditioner 01 according to the measured value of the air supply flow, the differential pressure transmitter 9 is also connected with the precision air conditioner controller 1, and when the actual air supply flow deviates from the preset air supply flow, the precision air conditioner controller 1 correspondingly increases or reduces the air supply flow according to the deviation value, so that the air supply cooling requirement of the machine room is met.
The lower air supply air conditioner air duct can prevent cold air from flowing backwards outwards after the fan is stopped by arranging the self-hanging type shutter 3 in the air duct main body 2; the air supply flow is measured by the Venturi nozzle 5, the nozzle outflow coefficient is stable, the resistance loss is small, the sensitivity to the change of the upstream air flow speed is low, and the measurement precision is higher; the front rectifying plate 4 and the rear rectifying plate 6 are arranged at the front end and the rear end of the Venturi nozzle 5, namely upstream and downstream, for rectifying, so that uniform air flow is formed, and the measurement precision is improved. The front static pressure sensor 7, the rear static pressure sensor 8, the precision air conditioner controller 1 and the like can be arranged by referring to the prior art.
It is right above that the utility model provides a lower air supply air conditioner wind channel has carried out detailed introduction. The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.
Claims (10)
1. The air duct of the air conditioner with the lower air supply is characterized by comprising an air duct main body (2) and an air quantity detection device arranged in the air duct main body (2); air volume detection device includes venturi nozzle (5), locates preceding cowling panel (4) before venturi nozzle (5) and locating back cowling panel (6) after venturi nozzle (5), venturi nozzle (5) with preceding static pressure sensor (7) are set up between preceding cowling panel (4), the throat of venturi nozzle (5) is equipped with back static pressure sensor (8), preceding static pressure sensor (7) with differential pressure transmitter (9) are connected in back static pressure sensor (8), differential pressure transmitter (9) are used for the basis preceding static pressure sensor (7) with the pressure differential calculation air supply flow that back static pressure sensor (8) detected.
2. The downdraft air conditioning duct of claim 1, wherein the front fairing (4) and the rear fairing (6) each comprise circular perforated plates arranged at equal intervals, and the ventilation holes of adjacent circular perforated plates are arranged oppositely.
3. The downdraft air conditioning duct of claim 1, wherein the differential pressure transmitter (9) is connected to a precision air conditioning controller (1);
when the air supply flow deviates from the preset value, the precision air conditioner controller (1) is used for controlling the precision air conditioner (01) to adjust the air supply flow.
4. The downdraft air conditioning duct of claim 1, wherein the duct body (2) is provided with an arc-shaped air inlet chamber for connecting an air outlet of a precision air conditioner (01), and the air outlet of the duct body (2) is connected to a raised floor plenum box.
5. The air duct of air conditioner with lower air supply according to claim 1, characterized in that the front fairing (4) and the venturi nozzle (5) are arranged alternately and in parallel, and the rear fairing (6) is attached to the air outlet of the venturi nozzle (5).
6. The downdraft air conditioning duct of claim 1, wherein the venturi nozzle (5) comprises a truncated cone-shaped inlet convergent section and an outlet divergent section and a cylindrical throat section connecting the inlet convergent section and the outlet divergent section, and the back static pressure sensor (8) is provided in the throat section.
7. The downdraft air-conditioning duct according to any one of claims 1 to 6, wherein self-hanging louvers (3) are further provided in the duct main body (2);
the self-hanging shutter (3) comprises an outer frame, rotating shafts which are rotatably connected with the outer frame and are arranged in parallel, and blades which are fixedly connected with the rotating shafts in a one-to-one correspondence mode.
8. The downdraft air conditioning duct of claim 7, wherein a gasket is provided between the outer frame and the inner wall of the duct body (2).
9. The downdraft air-conditioning duct according to claim 8, wherein an insulating layer is provided on an inner wall of the duct main body (2).
10. The under-draft air conditioning duct according to claim 9, wherein the diameter of a pressure-taking hole for mounting the front static pressure sensor (7) and the rear static pressure sensor (8) is 0.5 to 1.0mm, and the axis of the pressure-taking hole is perpendicular to the axis of the duct main body (2).
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| CN201922353031.6U CN211233299U (en) | 2019-12-23 | 2019-12-23 | Air duct of air conditioner with lower air supply |
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| CN201922353031.6U CN211233299U (en) | 2019-12-23 | 2019-12-23 | Air duct of air conditioner with lower air supply |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110887206A (en) * | 2019-12-23 | 2020-03-17 | 东莞深证通信息技术有限公司 | Air duct of air conditioner with lower air supply |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110887206A (en) * | 2019-12-23 | 2020-03-17 | 东莞深证通信息技术有限公司 | Air duct of air conditioner with lower air supply |
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