Liquid-blocking and gas-equalizing baffle plate and flooded evaporator adopting same and capable of preventing sucked gas from carrying liquid
By using a V-shaped liquid-absorbing baffle and filter in the evaporator, airflow and droplet fall are improved, solving the compressor damage problem caused by droplet splashing, and improving container space utilization and cooling capacity limit.
Patent Information
- Application Number
- CN202520145600.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-22
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-01-22
AI Technical Summary
In existing evaporators, liquid droplet splashing damages the compressor, and the container space utilization is low, resulting in poor airflow separation and a decrease in cooling capacity.
A V-shaped liquid-blocking and gas-equalizing baffle is used, with airflow blocking area and ventilation holes, combined with a filter screen to improve airflow circulation and droplet fall, thereby enhancing the gas-liquid separation effect.
It improves container space utilization, reduces the risk of droplets being drawn into the compressor, enhances cooling capacity limits and gas-liquid separation efficiency, and reduces pressure drop.
Smart Images
Figure CN223826524U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of refrigeration technology, and more specifically, to a gas equalization baffle and a flooded evaporator that prevents gas suction and liquid carryover. Background Technology
[0002] A refrigeration system mainly consists of a compressor, evaporator, condenser, and throttling device. Among them, the flooded evaporator is a heat exchange device with high heat transfer efficiency and is widely used in refrigeration systems.
[0003] During the process of refrigerant absorbing heat and evaporating, the evaporation and boiling caused by the temperature difference between the inside and outside of the heat exchange tubes of the flooded evaporator are often accompanied by a large number of liquid droplets splashing. The liquid refrigerant is sucked into the compressor before it is fully evaporated, which can damage the compressor. Therefore, the evaporator is often made of a larger container to cope with this, by leaving enough height space to ensure that the splashed droplets can fall back down.
[0004] Furthermore, the strong suction of the connected compressor exacerbates the risk of liquid carryover. When the evaporator unit's suction port is offset to the same side as the intense heat exchange and boiling section, the container's cooling capacity limit will be significantly reduced. Therefore, evaporators are typically designed with vapor distribution and liquid blocking devices to maximize their cooling capacity.
[0005] Currently, the most common type of liquid-blocking device is a gas distribution plate, which is placed between the liquid surface and the suction port to prevent gas from carrying refrigerant droplets into the compressor. These devices have the following disadvantages:
[0006] The planar baffle structure has poor droplet aggregation ability. After the droplets collide with the plate, they may adhere to the bottom of the plate and follow the airflow through the through hole to enter the upper part and be sucked into the compressor.
[0007] Orifice plates typically have numerous pores on the baffle plate, requiring sufficient opening area to ensure a relatively uniform airflow distribution below the plate. Since the gas mainly passes directly upward through the pores, it needs to be installed at a relatively high position above the liquid surface to ensure that the upward splashing droplets have enough space to fall back, resulting in low space utilization.
[0008] Although multi-stage baffles achieve gas-liquid separation through flow collisions between multiple baffles, the airflow generally still passes upward through the pores, resulting in weak lateral flow. A small number of baffles leads to poor separation, while a large number of baffles causes excessive pressure drop and occupies a large space.
[0009] There are other non-planar gas-liquid separation baffles, where all the airflow flows into the compressor through the side holes on both sides of the baffle. Due to the limited area of the side openings, the flow velocity near the openings is high and the pressure drop is large. Utility Model Content
[0010] The technical problem to be solved by this application is to provide a liquid-blocking and gas-equalizing baffle, a full-liquid evaporator using the baffle to prevent gas suction and liquid carry-over, and its refrigeration system, which significantly increases the maximum gas suction flow of the container and improves the space utilization of the container.
[0011] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0012] A liquid-blocking and gas-equalizing baffle, characterized in that,
[0013] The plate has a V-shaped, open-top cross-section, with the two plate surfaces forming the V-shape arranged obliquely and extending along the length of the plate.
[0014] Each panel is configured as follows: a flat, non-perforated airflow blocking area is provided, and ventilation holes of different sizes are arranged at both ends of the airflow blocking area. The ventilation holes are configured to gradually increase in total opening area and be denser along the distance away from the airflow blocking area, and gradually decrease in total opening area and be sparser along the distance closer to the airflow blocking area.
[0015] In the above technical solution, ventilation holes are only arranged at the two edges along the length direction, and the hole diameter varies from small to large or gradually changes along the length direction.
[0016] In the above technical solution, ventilation holes are arranged linearly along the length direction only at the two edges along the length direction, and the hole diameters vary from small to large or gradually change along the length direction.
[0017] In the above technical solution, multiple rows of ventilation holes are arranged in an alternating manner.
[0018] In the above technical solution, the airflow obstruction area is located in the center of the plate, and the ventilation holes are located at both ends of the plate along its length and are symmetrically arranged about the center of the plate.
[0019] In the above technical solution, the airflow blocking area is offset at one end of the plate, and the ventilation holes are arranged at both ends of the airflow blocking area and are respectively set close to both ends of the plate. The diameter of the ventilation hole at one end of the plate is much larger than that at the other end.
[0020] In the above technical solution, the back sides of the two plates forming the V-shape are provided with protrusions along the length of the plate body. The protrusions protrude from the back sides of the plate, so that the liquid can gather along the direction of the protrusions and fall back evenly downwards.
[0021] In the above technical solution, protrusions are provided on the back sides of the two plates forming the V-shape along the length of the plate body. These protrusions extend from the back sides of the plates and are perpendicular to the plates. This allows the droplets to disperse and fall back more easily.
[0022] In the above technical solution, multiple parallel, spaced protrusions are arranged on the back of the two plates forming the V-shape along the length of the plate. This allows the liquid flow to fall back from the multiple protrusions that act as guides.
[0023] A flooded evaporator designed to prevent gas and liquid intake, characterized in that:
[0024] The aforementioned liquid-blocking and gas-equalizing baffle is installed inside the evaporator cylinder, located below and close to the air intake, and the airflow blocking area at least covers the air intake.
[0025] At least one end of the liquid-blocking and gas-equalizing baffle has a set distance between its end and the tube sheet of the cylinder at that end to form a flow-around gap; below the liquid-blocking and gas-equalizing baffle, filter screens are laid flat at both ends of the cylinder along its length, with the filter screens located above the heat exchange tubes.
[0026] The filter at at least one end covers the gap at the end and a portion of the air distribution baffle area, so that the airflow flows laterally around the gap area to reach the air intake.
[0027] In the above technical solution, the aperture size of the through holes on the liquid-blocking and gas-equalizing baffle is set such that the airflow passing through the vent holes accounts for 10-30% of the total airflow reaching the intake port. That is, the main airflow flows laterally around the gap at both ends to reach the intake port.
[0028] In the above technical solution, when the air intake is offset at one end of the cylinder length direction, the airflow blocking area is offset at the same end of the plate and located below the air intake. The filter at the offset end extends towards the center to cover the air intake.
[0029] In the above technical solution, the filter screen is laid obliquely and fixed on the back of the liquid-blocking and gas-equalizing baffle.
[0030] In the above technical solution, the filter screen is laid horizontally close to the heat exchange tube.
[0031] In the above technical solution, the liquid-blocking and gas-equalizing baffle is arranged above the container near the air inlet, with a length of 60%-80% of the container length.
[0032] Furthermore, this utility model also provides a refrigeration system, characterized by employing a flooded evaporator that prevents air intake and liquid carryover.
[0033] Therefore, this invention utilizes a V-shaped liquid-blocking and gas-equalizing baffle, with a relatively long distance between the baffle end and the tube sheet to create a flow-around gap. The inclined surface structure allows droplets adhering to the bottom of the baffle to slide down and converge. The perforation pattern is as follows: no perforation is made directly below the air intake; perforations near the air intake are sparse or small; and perforations further away from the air intake are dense or large. Multiple liquid-guiding strips are arranged on the inclined surface.
[0034] While enhancing the droplet aggregation capacity of the baffle, the flow around the gas changes the gas path, causing the airflow to flow laterally around to the end opening and then converge into the compressor. This prolongs the residence time of the droplets under the evaporator plate, allowing the droplets mixed in the airflow to fall back effectively under gravity when they splash laterally, thus undergoing secondary evaporation.
[0035] Unevenly sized air holes are axially opened on both sides of the V-shaped baffle to improve the flow field below and reduce the resistance loss caused by the baffle. Since the air holes on both sides are high enough from the liquid surface, the proportion of airflow passing through is small, and it is difficult for droplets to splash up from the air holes.
[0036] At the same time, the large volume of gas collected at both ends and the high gas velocity allow for the installation of filter screens to capture liquid droplets, reducing the risk of liquid carryover during air intake and having only a slight impact on pressure drop.
[0037] Compared with the prior art, the present invention has at least the following beneficial effects:
[0038] A V-shaped baffle is provided below the air intake. By extending the gas's travel distance inside the container through flow around it, the liquid in the gaseous refrigerant is prevented from being carried over, reducing the space height requirement. Compared with using a porous gas equalization plate, it has the advantages of convenient processing and high container space utilization.
[0039] The anti-liquid-carrying device using a V-shaped gas equalization baffle and filter assembly increases the travel distance of the airflow generated by bottom evaporation inside the container, prolongs the residence time of droplets below the baffle, improves gas-liquid separation efficiency, allows for a smaller evaporator size, allows for the arrangement of more heat exchange tubes inside the evaporator, reduces the safety height requirement of the baffle from the liquid surface, and improves the space utilization of the container.
[0040] Different V-shaped baffle solutions are used for units with centered and offset suction ports to maximize the container's cooling capacity. A filter screen is installed at the bottom near the liquid surface, with a length sufficient to cover the distance between the tube sheet and the V-shaped baffle, preventing splashed droplets from being directly sucked into the compressor suction port. When the suction port is centered, a certain amount of space is left between the V-shaped baffle and both sides of the tube sheet; when the suction port is offset, the end of the baffle on the offset side will be pressed tightly against the tube sheet on that side, while multiple small airflow channels are opened at the edge as an alternative.
[0041] The baffle edge is welded and fixed to the container, and air passages are provided at the edge. This device helps to improve the airflow velocity and temperature field inside the container, reduce the pressure drop near the air intake, suppress the phenomenon of liquid carrying during air intake, and the liquid droplets gather and fall back under the baffle, dripping onto the top of the bottom heat exchange tube to participate in heat exchange. Using a method similar to falling film to replace the refrigerant soaking heat exchange tube can reduce the amount of refrigerant filling and further reduce costs.
[0042] The V-shaped baffle, with its high sides and low center, enhances the ability of droplet aggregation. Multiple liquid guide strips are set on the inclined surface of the baffle, allowing the large droplets that have converged to fall back more evenly above the heat exchange tube, achieving an effect similar to a falling film distributor. This also has the advantage of saving refrigerant charge.
[0043] The V-shaped baffle has airflow holes of different sizes on both sides of its edge, which improves the airflow field inside the container and reduces local pressure loss.
[0044] The filters are located on the left and right sides of the container, which can effectively intercept splashing droplets and minimize the risk of liquid being carried in during air intake. At the same time, the pressure loss is small, and the maximum air intake flow rate of the container can be significantly increased compared to not using filters.
[0045] This type of heat exchanger saves container space and refrigerant volume, allowing for the arrangement of more heat exchange tubes, solving the problem of liquid carryover during evaporator suction, achieving the goal of large cooling capacity in a small cylinder, and offering better cost performance. Attached Figure Description
[0046] To more clearly illustrate the technical solutions of the embodiments of this application, 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 application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0047] Figure 1 This is a schematic diagram of the flooded evaporator of Embodiment 1 of this utility model.
[0048] Figure 2 This is a schematic diagram of the internal flow of the evaporator in Embodiment 1 of this utility model.
[0049] Figure 3 This is a structural diagram of the liquid-blocking and gas-equalizing baffle of Embodiment 1 of this utility model.
[0050] Figure 4 This is a schematic diagram of the flooded evaporator of Embodiment 2 of this utility model.
[0051] Figure 5 This is a structural diagram of the liquid-blocking and gas-equalizing baffle of Embodiment 2 of this utility model.
[0052] Figure 6 This is a diagram showing the filter screen and V-shaped baffle fixing structure of Embodiment 3 of this utility model.
[0053] Figure 7 This is a diagram showing the filter screen and V-shaped baffle fixing structure of Embodiment 4 of this utility model. Detailed Implementation
[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0055] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0056] 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.
[0057] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "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 application based on the specific circumstances.
[0058] The features and performance of this application will be further described in detail below with reference to the embodiments.
[0059] Example 1:
[0060] As attached Figure 1 The flooded evaporator mainly consists of an evaporator shell 1, a heat exchange tube group 2, a V-shaped baffle 3, a filter screen 4, an air intake 5, and an evaporator tube sheet 6. A certain distance is left between the end of the V-shaped baffle and the tube sheet, and the evaporation airflow has a short path into the upper channel at this point. Therefore, the filter screen 4 is set between the heat exchange tube group 2 and the V-shaped baffle 3 on the left and right sides of the container to minimize the risk of liquid carryover during air intake.
[0061] Furthermore, the V-shaped baffle structure proposed in this utility model provides better anti-liquidity protection, and its structure is described as follows:
[0062] V-shaped baffles 3 are positioned above the container near the intake port 5, with a length of 60%-80% of the shell 1. They are higher on both sides and lower in the middle, and the edges of the baffles are welded to the shell 1 to prevent liquid carryover during suction caused by wall-mounted flow. The airflow generated by evaporation outside the heat exchange tubes flows laterally along the bottom of the V-shaped baffles 3, entering the upper flow channel from the left and right sides of the baffles 3, and then converging into the intake port 5. This flow around the gas extends its travel distance inside the container, preventing liquid carryover of the gaseous refrigerant and making more efficient use of the internal space of the container, reducing the need for increased height.
[0063] Figure 2 The flow of the gas and liquid phases inside the evaporator is shown. The gaseous refrigerant flow G inside the shell 11 is as shown by the red streamline, and the liquid refrigerant L is as shown by the blue streamline. The airflow below the baffle has a longer path, and the liquid droplets it carries are more likely to fall back.
[0064] At the same time, air passages 31 are provided at the edge, as shown in the attached figure. Figure 3 As shown, its structural form can be a round hole, a square hole, or other shapes. The opening follows the rule of "smaller near the air inlet, larger farther away, and none below," meaning the total opening area near the air inlet is small, the total opening area farther away is large, and there is no opening directly below the air inlet, showing a gradient or gradual change in size along the length direction. 10-30% of the airflow generated by evaporation in the shell 1 directly enters the air inlet 5 through the through-hole 31, reducing the velocity of the concentrated airflow on the left and right sides. Simultaneously, because the airflow through-hole is located at a relatively high position inside the container, droplets are less likely to be carried in through the through-hole, reducing the risk of liquid carryover and improving the pressure drop. Multiple liquid guide strips 32 are set on the inclined surface. After the droplets splashed from the bottom are impacted by the airflow and hit the baffle, they quickly gather into large liquid columns on the inclined surface of the baffle under the action of gravity. They fall back through the liquid guide strips 32 and drip evenly onto the top row of heat exchange tubes 2, and participate in heat exchange again. Therefore, the evaporator does not need to immerse all the heat exchange tubes with refrigerant as usual. The heat exchange effect can be guaranteed by a concept similar to falling film, and the amount of refrigerant charged can be reduced.
[0065] Example 2
[0066] like Figure 4 and 5 The air intake 5 is offset at one end of the cylinder. At this time, the flat, non-perforated airflow blocking area is located below the air intake. Below the air intake, the filter screen 4 extends to cover the projected area of the air intake and continues to extend towards the middle to avoid liquid being carried in by the air intake. At this time, the transverse flow reaches the V-shaped baffle 3 from the transverse flow gap at one end and then reaches the air intake.
[0067] like Figure 5As shown, the vent holes 31 can be arranged in multiple rows or in a single row. The vent holes 31 on both sides can be arranged in multiple staggered rows, which improves the pressure loss and flow field. Multiple liquid guiding strips 32 are set on the inclined surface, through which the liquid falls back.
[0068] Example 3
[0069] Based on Examples 1 and 2, filter 4 can be configured as follows: Figure 6 As shown, it is fixed to the back of the inclined surface of the V-shaped baffle 3 and laid at an angle. The droplets captured by the filter fall back more easily, and the combination with the baffle has a better liquid-blocking effect.
[0070] Example 4
[0071] Based on Examples 1 and 2, filter 4 can be configured as follows: Figure 7 As shown, the tubes are laid flat above the heat exchange tube group 2, while maintaining a certain distance from the back of the inclined surface of the V-shaped baffle 3; for example, they are fixed to the heat exchange tube support plate. The droplets carried below the baffle are filtered and fall back earlier, ensuring the purity of the upper airflow.
[0072] Example 5
[0073] Based on the above embodiments 1-4, the suction pipe 5 can be set as a variable diameter pipe, which can be expanded, contracted or combined in multiple sections, resulting in a smaller pressure loss in the heat exchanger.
[0074] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
Claims
1. A liquid-blocking and gas-equalizing baffle, characterized in that, The plate has a V-shaped, open-top cross-section, with the two plate surfaces forming the V-shape arranged obliquely and extending along the length of the plate. Each panel is configured as follows: a flat, non-perforated airflow blocking area is provided, and ventilation holes of different sizes are arranged at both ends of the airflow blocking area. The ventilation holes are configured to gradually increase in total opening area and be denser along the distance away from the airflow blocking area, and gradually decrease in total opening area and be sparser along the distance closer to the airflow blocking area.
2. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, Ventilation holes are provided only at the two edges along the length direction.
3. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, Ventilation holes are arranged linearly along the length direction only at the two edges along the length direction.
4. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, The airflow obstruction area is located in the center of the plate, and the ventilation holes are located at both ends of the plate along its length and are symmetrically arranged about the center of the plate.
5. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, The airflow blocking area is offset at one end of the plate, and the vents are arranged at both ends of the airflow blocking area and are respectively set close to both ends of the plate. The diameter of the vent at one end of the plate is much larger than that at the other end.
6. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, The two plates forming the V-shape have raised strips on their back sides along the length of the plate. The raised strips protrude from the back sides of the plates, allowing the liquid to collect along the raised strips and fall back evenly downwards.
7. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, The two plates forming the V-shape have raised strips on their back sides along the length of the plate. The raised strips protrude from the back sides of the plates and are perpendicular to the plates.
8. The liquid-blocking and gas-equalizing baffle according to claim 1, characterized in that, Multiple parallel, spaced ridges are set on the back of the two plates that form a V-shape along the length of the plate.
9. A flooded evaporator designed to prevent gas and liquid carryover, characterized in that: The liquid-blocking and gas-equalizing baffle according to any one of claims 1-8 is disposed in the evaporator cylinder, located below and close to the air intake, and the airflow blocking area at least covers the air intake. At least one end of the liquid-blocking and gas-equalizing baffle has a set distance between its end and the tube sheet of the cylinder at that end to form a flow-around gap; below the liquid-blocking and gas-equalizing baffle, filter screens are laid flat at both ends of the cylinder along its length, with the filter screens located above the heat exchange tubes. The filter at at least one end covers the gap at the end and a portion of the air distribution baffle area, so that the airflow flows laterally around the gap area to reach the air intake.
10. The flooded evaporator with anti-vapor suction and liquid carryover protection according to claim 9, characterized in that: The aperture size of the through holes on the liquid-blocking and gas-equalizing baffle is set such that the airflow passing through the vent hole accounts for 10-30% of the total airflow reaching the intake port.
11. The flooded evaporator with anti-vapor suction and liquid carryover protection according to claim 9, characterized in that: When the air intake is offset at one end of the cylinder length direction, the airflow blocking area is offset at the same end of the plate and located below the air intake. The filter at the offset end extends towards the center to cover the air intake.
12. The flooded evaporator with anti-vapor suction and liquid carryover protection according to claim 9, characterized in that: The filter screen is laid flat at an angle and fixed to the back of the liquid-blocking and gas-equalizing baffle.
13. The flooded evaporator with anti-vapor suction and liquid carryover protection according to claim 9, characterized in that: The filter screen is laid horizontally close to the heat exchange tube.
14. The flooded evaporator with anti-vacuum and liquid-carrying protection according to claim 9, characterized in that: The liquid-blocking and gas-equalizing baffle is arranged above the container near the air inlet, with a length of 60%-80% of the container length.
15. A refrigeration system, characterized in that... The flooded evaporator with anti-vacuum and liquid-carrying features described in any one of claims 9-14.