Active chilled beam air supply tail end device based on wall-attached jet flow and active chilled beam air conditioning system based on active chilled beam air supply tail end device

Abstract

The utility model discloses an active chilled beam air supply tail end device based on wall-attached jet flow and an active chilled beam air conditioning system based on the active chilled beam air supply tail end device. The active chilled beam air supply tail end device comprises a static pressure box, a finned tube type heat exchanger, a mixing cavity and an induced air return cavity. The static pressure box is arranged at the top of the inner side of the mixing cavity, a plurality of primary air jet nozzles are arranged at the bottom of the static pressure box, the primary air jet nozzles are gradually-shrunk nozzles and distributed at intervals, the static pressure box communicates with the mixing cavity through the primary air jet nozzles, and the mixing cavity communicates with the induced air return cavity. The finned tube type heat exchanger is arranged between the mixing cavity and the induced air return cavity, a slot type air supply outlet is formed in the bottom of the mixing cavity, and the position of the slot type air supply outlet is close to the side wall of a room. The wall-attached jet flow air supply mode is adopted for air supply, the designed air volume needed by traditional mixed air supply is reduced, the efficiency of traditional cold beam mixed air supply is improved, the induction ratio is increased, the operation cost is reduced, and the indoor thermal comfort is improved.

Description

Technical Field

[0001] This utility model belongs to the field of HVAC technology, and in particular to an active cold beam air supply terminal device based on wall-mounted jet and an active cold beam air conditioning system based thereon. Background Technology

[0002] With technological advancements and changing lifestyles, people spend approximately 80% of their time indoors each day. Therefore, indoor air quality is crucial for work efficiency, comfort, and health. Air conditioning can adjust indoor air temperature and other parameters according to user needs, allowing people to work and live comfortably in different seasons, outdoor weather conditions, and even extreme outdoor conditions. However, air conditioning also accounts for a significant portion of energy consumption. In China, building energy consumption accounts for nearly 30% of the country's total energy consumption, with central air conditioning systems consuming approximately 50% to 70%, and even reaching 80% in some public buildings. Therefore, optimizing HVAC systems for energy conservation is essential while ensuring thermal comfort. The air supply terminal, as the interface between the system and the indoor environment, directly affects the rationality of indoor airflow organization, the uniformity of thermal and humidity, and the overall energy consumption of the system. Energy-saving design of the air supply terminal is one feasible approach.

[0003] Different combinations of air supply and exhaust methods at the air conditioning terminal create different airflow patterns. Airflow pattern is a direct technical manifestation of the air conditioning system's effect on human comfort, significantly impacting energy consumption and indoor thermal comfort. Different combinations of supply and exhaust methods can create various airflow patterns, controlling the room's thermal and humidity environment and energy efficiency. Traditional air conditioning terminals exhibit a mixed ventilation mode, where the supply airflow is fully mixed with indoor air before being distributed throughout the room. While simple and easy to implement, this mode suffers from low efficiency. Displacement ventilation, as an advanced airflow pattern, introduces low-speed, low-temperature fresh air from the bottom of the room, allowing it to rise naturally due to buoyancy, carrying hot indoor air upwards and exhausting it through high-level exhaust vents. This creates a more rational airflow path and has proven to be a more efficient airflow pattern. It not only effectively reduces temperature stratification and improves human comfort but also significantly reduces energy consumption, performing particularly well in applications requiring good air quality and efficient heat recovery. However, since the original design of the cold beam was to adapt to the mixed ventilation mode, while the displacement ventilation requires the air outlet to be low and the air velocity to be slow, there is a mismatch between the two in terms of structural design and operation control, and it is difficult to combine the cold beam with the air supply. Summary of the Invention

[0004] The purpose of this invention is to provide an active cold beam air supply terminal device based on wall-mounted jet and an active cold beam air conditioning system based thereon, so as to solve the problem of low air supply efficiency of existing cold beam terminal devices.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An active cold beam air supply terminal device based on wall-mounted jet includes a static pressure box, a finned tube heat exchanger, a mixing chamber, and an induced return air chamber;

[0007] The static pressure box is located on the inner top of the mixing chamber. The bottom of the static pressure box is provided with several primary air jet nozzles. The primary air jet nozzles are tapered nozzles and are spaced apart. The static pressure box and the mixing chamber are connected through the primary air jet nozzles. The mixing chamber is connected to the induced return air chamber. The finned tube heat exchanger is located between the mixing chamber and the induced return air chamber. The bottom of the mixing chamber is provided with a slotted air outlet, which is located close to the side wall of the room.

[0008] Furthermore, a primary air connection port is provided on one side of the static pressure box, and the primary air connection port passes through the side wall of the mixing chamber and communicates with the primary air supply port.

[0009] Furthermore, the spacing between the primary air jet nozzles is 2 to 4 times the nozzle diameter.

[0010] Furthermore, the primary air jet nozzle is positioned directly above the slotted air outlet, and the centerline of the slotted air outlet is aligned with the centerline of the plurality of primary air jet nozzles.

[0011] Furthermore, the static pressure chamber, mixing chamber, and induced return air chamber are of equal length.

[0012] Furthermore, an induced return air inlet is provided at the bottom of the induced return air chamber.

[0013] Furthermore, the refrigerant connection method of the finned tube heat exchanger is a double-pipe or four-pipe system, and the inlet and outlet of the water pipe on the finned tube heat exchanger pass through the side wall of the induced return air cavity and are connected to the outside.

[0014] Furthermore, the refrigerant temperature of the finned tube heat exchanger is 14~18℃.

[0015] Furthermore, the air supply induction ratio of the active cold beam air supply terminal device is greater than 1.2.

[0016] An active cooling beam air conditioning system includes the aforementioned active cooling beam air supply terminal device.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention provides an active cold beam air supply terminal device based on wall-mounted jets. A static pressure box is placed at the top inner side of the mixing chamber, and several primary air jet nozzles are installed at the bottom of the static pressure box. The static pressure box and the mixing chamber are connected through these primary air jet nozzles. The primary air supply converts dynamic pressure to static pressure within the static pressure box and is then ejected at high speed into the mixing chamber through the primary air jet nozzles. The mixing chamber is connected to an induced return air chamber, and a finned tube heat exchanger is placed between the mixing chamber and the induced return air chamber. After heat exchange with the indoor induced return air drawn into the induced return air chamber, it mixes with the primary air supply ejected at high speed from the primary air jet nozzles in the mixing chamber. The primary air jet nozzles are tapered nozzles and spaced apart to optimize the induction effect and achieve the maximum induction ratio. A slotted air outlet is created at the bottom of the mixing chamber, positioned close to the room's side wall to form a wall-mounted jet airflow pattern. This allows the air to flow along the wall or ceiling, reducing eddies and turbulence, and delivering the mixed air into the room. This results in a more uniform indoor air distribution, improving indoor temperature comfort and achieving a complete cycle from supply to return air. This invention abandons the traditional cold-beam mixing airflow method, employing a wall-mounted jet airflow pattern, which reduces the design air volume required for traditional mixing airflow and overcomes the low efficiency of traditional mixing airflow to some extent. Indoor air enters the plenum chamber and, after heat exchange with the finned-tube heat exchanger, reaches the indoor design temperature, bearing part of the room load. This reduces the fresh air volume required for traditional slotted air outlets, while also improving indoor thermal stratification, increasing the efficiency of traditional cold-beam mixing airflow, increasing the induction ratio, reducing operating costs, and saving building space. Meanwhile, the air supply of this utility model is delivered directly into the personnel work area through wall-mounted jets, which effectively avoids the energy waste problem of whole-space air supply, improves the problem of personnel being in the return air zone, and enhances the thermal comfort and air quality of the personnel work area.

[0019] Furthermore, the determination of the dimensions, relative positions, and resistance losses of the primary air jet nozzle in the mixing chamber, the slotted air outlet, the finned tube heat exchanger in the induced return air chamber, and the induced return air outlet in this utility model effectively ensures the uniformity of the induction ratio and the wall-mounted jet air supply, improves the thermal comfort of indoor occupants, and is suitable for various indoor environments that require efficient air supply. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1This is a schematic diagram of the active cold beam air supply terminal device based on wall-attached jet according to this utility model.

[0022] Figure 2 The three-view diagram shows the structure of the active cold beam air supply terminal device based on wall-attached jet of this utility model.

[0023] Figure 3 This is a velocity and streamline cloud diagram of the active cold beam air supply terminal device based on wall-attached jet of this utility model.

[0024] Figure 4 This is a temperature cloud map of the active cold beam air supply terminal device based on wall-attached jet according to this utility model.

[0025] Wherein: 1- Primary air connection port, 2- Static pressure box, 3- Primary air jet nozzle, 4- Slit-type air outlet, 5- Induced return air outlet, 6- Finned tube heat exchanger, 7- Mixing chamber, 8- Induced return air chamber, 9- Water pipe. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0028] To enable those skilled in the art to understand the features and effects of this utility model, the terms and expressions mentioned in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding this utility model, and in case of conflict, the definitions in this specification shall prevail.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] In the description of the embodiments of this utility model, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the utility model. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0032] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0033] The present invention will now be described in further detail with reference to the accompanying drawings:

[0034] See Figure 1 This invention provides an active cold beam air supply terminal device based on wall-mounted jet, comprising a primary air connection port 1, a static pressure box 2, a primary air jet nozzle 3, a slotted air supply outlet 4, an induced return air outlet 5, a finned tube heat exchanger 6, a mixing chamber 7, an induced return air chamber 8, and a water pipe 9. The static pressure box 2 is located on the inner top of the mixing chamber 7, and the mixing chamber 7 is connected to the induced return air chamber 8. The three regions—static pressure box 2, mixing chamber 7, and induced return air chamber 8—are of equal length, ranging from 0.8 to 1.2 meters.

[0035] A primary air connection port 1 is provided on one side of the static pressure box 2. The primary air connection port 1 is located in the center of the side of the static pressure box 2. The primary air connection port 1 passes through the side wall of the mixing chamber 7 and connects to the primary air supply port. The primary air enters the static pressure box 2 through the primary air connection port 1, and the dynamic pressure is converted into static pressure. Several primary air jet nozzles 3 are arranged sequentially at the bottom of the static pressure box 2. The primary air jet nozzles 3 are tapered nozzles with a diameter of 6~10mm. The primary air jet nozzles 3 are spaced apart, with the spacing between them being 2~4 times the nozzle diameter, to optimize the induction effect and obtain the maximum induction ratio. The static pressure box 2 and the mixing chamber 7 are connected through the primary air jet nozzles 3, allowing the primary air in the static pressure box 2 to be ejected at high speed into the mixing chamber 7.

[0036] A slotted air inlet 4 is provided at the bottom of the mixing chamber 7 as the air supply outlet for the room. Primary air jet nozzles 3 are positioned directly above the slotted air inlet 4, at a distance of 0.1~0.2m. The centerline of the slotted air inlet 4 is aligned with the centerline connecting the centers of several primary air jet nozzles 3. The device is arranged on the side wall of the room, with the slotted air inlet 4 close to the side wall. The distance between the slotted air inlet 4 and the rear wall of the device is 0.03~0.1m, and the aspect ratio of the slotted air inlet 4 ranges from 1.2 to 1.8. After the primary air supply and induced return air are mixed, they are delivered into the room through the slotted air inlet 4. The air supply is based on the Coanda effect, forming a vertical wall-attached jet, ensuring that the air supply non-uniformity of the slotted air inlet 4 is less than 10%.

[0037] like Figure 2 As shown, the finned tube heat exchanger 6 is located between the mixing chamber 7 and the induced return air chamber 8. The refrigerant connection of the finned tube heat exchanger 6 is a double-pipe or four-pipe connection. A water pipe 9 is installed on the finned tube heat exchanger 6. The inlet and outlet of the water pipe 9 pass through the side wall of the induced return air chamber 8 and are connected to an external cold or heat source to provide refrigerant for the finned tube heat exchanger 6. Considering practical engineering requirements and to avoid condensation on the heat exchanger surface, the refrigerant temperature inside the finned tube heat exchanger 6 is selected to be 14~18℃. An induced return air inlet 5 is opened at the bottom of the induced return air chamber 8, which draws indoor air into the induced return air chamber 8 by relying on the negative pressure within the chamber. The airflow delivered by the slotted air outlet 4 should avoid being directly drawn into the induced return air cavity 8 through the induced return air outlet 5. Therefore, the indoor design temperature is controlled by the finned tube heat exchanger 6 so that the temperature of the airflow drawn into the induced return air outlet 5 is not lower than the indoor design temperature when the cooling operation is in operation, and the temperature of the airflow drawn into the induced return air cavity 6 by the induced return air outlet 5 is not higher than the indoor design temperature when the heating operation is in operation.

[0038] The working method of the active cold beam air supply terminal device based on wall-attached jet of this utility model:

[0039] When the active cold beam air supply terminal device based on wall jet is working, the primary air supply first enters the static pressure box 2 through the primary air connection port 1. The static pressure box 2 converts the primary air supply into static pressure. After the pressure in the static pressure box 2 stabilizes, it is ejected at high speed through the primary air jet nozzle 3 into the mixing chamber 7. During the process of moving to the slot-type air supply port 4, a negative pressure induction effect is formed in the induced return air chamber 8.

[0040] The induced return air in the room enters the induced return air cavity 8 through the induced return air inlet 5 under the combined action of the induction and buoyancy of the primary air supply, and then undergoes heat exchange with the surface of the finned tube heat exchanger 6.

[0041] The air is mixed with the primary air supply in the mixing chamber 7, and the mixed air supply is then delivered into the room through the slotted air outlet 4. Assisted by the room's side walls, a wall-attached jet air supply mode is formed based on the Coanda effect, achieving air circulation. Figure 3 and Figure 4 As shown.

[0042] In this invention, primary air enters the static pressure box 2 through the primary air connection port 1, and after pressure stabilization, it is ejected into the mixing chamber 7 through the primary air jet nozzle 3. The primary air supply volume is Q1. Under the action of the turbulent airflow and the temperature difference of the finned tube heat exchanger 6, a negative pressure is generated at the center of the device, causing the indoor air to enter the induced return air chamber 8 through the induced return air port 5, which is the secondary air supply volume Q2.

[0043] The induction ratio of the cold beam air supply is:

[0044] ζ

[0045] Where ζ is the cold beam air supply induction ratio, and Q1 is the primary air supply volume (m³). 3 / s), Q2 is the secondary air supply volume (m³ / s), 3 / s).

[0046] As mentioned above, the key to determining the induction ratio is the ratio of primary air supply volume to secondary air supply volume. The key factor affecting the primary air supply volume is the air intake volume of the primary air connection port 1 on the static pressure box 2. The primary air supply volume can be changed by changing the cross-sectional area A of the primary air connection port 1. Here, A is taken as 0.01m³. 2 0.0081m 2 0.0064m 2 The structural parameters of the primary air jet nozzle 3 are the decisive factors affecting the induction effect. The nozzle outlet diameter d is 10mm, 8mm and 6mm, the nozzle spacing is nd and n is 2, 3 and 4. The experimental results of the induction ratio are shown in Table 1.

[0047] Table 1. Experimental Operating Conditions for Induction Ratio

[0048]

[0049] Using a linear regression model to fit the relationship between the induction ratio ζ and the primary air area A, nozzle diameter d, and nozzle spacing nd, the following results are obtained:

[0050]

[0051] Where A is the cross-sectional area of ​​the primary air outlet (m²) 2 ), d is the diameter of the primary air jet nozzle (mm), and nd is the nozzle spacing (n≥2) (mm).

[0052] In this fitting, the correlation coefficient was close to 0.9791, indicating that the model has a high degree of fit to the induction ratio.

[0053] The airflow enters the induced return air chamber 8 from the induced return air inlet 5, and after flowing through the finned tube heat exchanger 6, a pressure drop ΔP will be generated. The test results of the pressure drop are shown in Table 2.

[0054] Table 2 Pressure Drop Test Conditions

[0055]

[0056] Using a linear regression model to fit the relationship between the preheating pressure and the primary air area A, nozzle diameter d, and nozzle spacing nd, the preheating pressure P is obtained as follows:

[0057]

[0058] The pressure drop is:

[0059]

[0060]

[0061] = ( )

[0062] Where ΔP is the pressure drop, p is the resistance of the finned tube heat exchanger 6, and A is the primary air area in square meters (m²). 2 ); d is the nozzle diameter in millimeters (mm); nd is the nozzle spacing in millimeters (mm); K is the drag coefficient of the fin structure; G is the airflow rate per unit area; This refers to air density.

[0063] In this fitting, the correlation coefficient was close to 0.9466, indicating that the model has a high degree of fit to the pressure drop.

[0064] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An active cold beam air supply terminal device based on wall-mounted jet, characterized in that, It includes a static pressure box (2), a finned tube heat exchanger (6), a mixing chamber (7), and an induced return air chamber (8); The static pressure box (2) is located on the inner top of the mixing chamber (7). The bottom of the static pressure box (2) is provided with a number of primary air jet nozzles (3). The primary air jet nozzles (3) are tapered nozzles and are spaced apart. The static pressure box (2) and the mixing chamber (7) are connected through the primary air jet nozzles (3). The mixing chamber (7) is connected to the induced return air chamber (8). The finned tube heat exchanger (6) is located between the mixing chamber (7) and the induced return air chamber (8). The bottom of the mixing chamber (7) is provided with a slotted air outlet (4). The slotted air outlet (4) is located close to the side wall of the room.

2. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The static pressure box (2) has a primary air connection port (1) on one side, and the primary air connection port (1) passes through the side wall of the mixing chamber (7) and communicates with the primary air supply port.

3. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The spacing between the primary air jet nozzles (3) is 2 to 4 times the nozzle diameter.

4. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The primary air jet nozzle (3) is positioned directly above the slotted air outlet (4), and the center line of the slotted air outlet (4) is aligned with the center line connecting the centers of the primary air jet nozzles (3).

5. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The static pressure chamber (2), the mixing chamber (7), and the induced return air chamber (8) are of equal length.

6. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The bottom of the induced return air chamber (8) is provided with an induced return air inlet (5).

7. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The refrigerant connection of the finned tube heat exchanger (6) is a double pipe or a four pipe. The inlet and outlet of the water pipe (9) on the finned tube heat exchanger (6) pass through the side wall of the induced return air cavity (8) and are connected to the outside.

8. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The refrigerant temperature of the finned tube heat exchanger (6) is 14~18℃.

9. The active cold beam air supply terminal device based on wall-mounted jet according to claim 1, characterized in that, The air supply induction ratio of the active cold beam air supply terminal device is greater than 1.

2.

10. An active cooling beam air conditioning system, characterized in that, Includes the active cold beam air supply terminal device as described in any one of claims 1 to 9.

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