Design method of a mixed flow machine structure and use thereof

Abstract

The application provides a design method of a mixed-flow structure, comprising: designing a plurality of mixed-flow structures, wherein each mixed-flow structure comprises a plurality of mixed-flow regions configured with a plurality of blade arrays, and the plurality of blade arrays are inclined in different directions; determining a plurality of mixed-flow planes of each mixed-flow structure respectively, wherein the mixed-flow plane is determined based on an interface formed by airflow passing through adjacent blade arrays; determining a partition correction coefficient, a distance correction coefficient and a mixing area coefficient of each mixed-flow plane respectively; calculating a mixed-flow coefficient of each mixed-flow structure according to the partition correction coefficient, the distance correction coefficient and the mixing area coefficient of each mixed-flow plane of each mixed-flow structure; and determining a target mixed-flow structure from the plurality of mixed-flow structures according to the mixed-flow coefficient of each mixed-flow structure.

Description

Technical Field

[0001] This invention relates to the field of mixer design, and more particularly to a design method for a mixer structure. Background Technology

[0002] In relevant standards for measuring the cooling and heating capacity of unitary air conditioners, the air enthalpy difference method is commonly used by manufacturers for rapid product testing due to its advantages of low investment and fast measurement. The laboratory built based on this method is called an enthalpy difference chamber. Inside the enthalpy difference chamber, a mixer is often installed before the air-side capacity sampling device to ensure a more uniform temperature and humidity distribution of the air after heat exchange, thus accurately measuring the heat exchange capacity of the air conditioning heat exchanger and air heat exchanger. The mixer not only facilitates the design and manufacturing of heat exchange samples but also avoids energy waste caused by repeated measurements due to measurement errors.

[0003] Current standards only describe whether mixing is necessary and the practice of mixing mixers, but do not specify the relevant requirements. Related research also does not specify the details of mixers. Therefore, it is necessary not only to design a high-efficiency mixer, but also to clearly identify the structural factors that affect the efficiency of the mixer, and to form a complete guideline for mixer design. Summary of the Invention

[0004] In view of the above, in order to at least partially solve at least one of the aforementioned technical problems, the present invention provides a design method for a mixer structure, comprising:

[0005] Design multiple mixer structures, each mixer structure including multiple mixing zones configured with blade arrays, the multiple blade arrays being tilted in different directions relative to each other;

[0006] Multiple mixing planes are determined for each mixer structure, based on the interfaces formed by airflows passing through multiple adjacent blade arrays.

[0007] The partition correction coefficient, distance correction coefficient, and mixing region coefficient of each mixing plane are determined respectively. The partition correction coefficient is used to characterize the air volume relationship of the multiple airflows forming the mixing plane. The distance correction coefficient is used to characterize the relationship between the theoretical maximum distance and the actual maximum distance traveled by the multiple airflows during the mixing process. The mixing region coefficient is used to characterize the relationship between the theoretical mixing area and the actual mixing area of ​​the mixing plane.

[0008] Based on the partition correction coefficient, distance correction coefficient and mixing region coefficient of each mixing plane of each mixer structure, the mixing coefficient of each mixer structure is calculated. The mixing coefficient is used to characterize the mixing effect of the mixer structure.

[0009] The target mixer structure is determined from multiple mixer structures based on the mixing coefficient of each mixer structure.

[0010] According to an embodiment of the present invention, each mixer structure includes m vertical mixing planes and n horizontal mixing planes among its multiple mixing planes;

[0011] Based on the partition correction coefficient, distance correction coefficient, and mixing region coefficient of each mixing plane in each mixer structure, the mixing coefficient of each mixer structure is calculated as follows:

[0012] The mixing coefficient of each vertical mixing plane is determined based on its respective partition correction coefficient, distance correction coefficient, and mixing area coefficient.

[0013] The vertical mixing coefficient is determined based on the mixing coefficients of each of the m vertical mixing planes;

[0014] The mixing coefficient of each horizontal mixing plane is determined based on its respective partition correction coefficient, distance correction coefficient, and mixing area coefficient.

[0015] Determine the horizontal mixing coefficient based on the mixing coefficient of each of the n horizontal mixing planes;

[0016] The mixing coefficient of each mixer structure is obtained based on the vertical mixing coefficient and the horizontal mixing coefficient.

[0017] According to an embodiment of the present invention, determining the partition correction factor, distance correction factor, and mixing region factor for each mixing plane includes:

[0018] The partition correction coefficient is determined based on the area ratio of two adjacent blade arrays.

[0019] The distance correction factor is determined based on the ratio of the theoretical maximum distance traveled by the airflow during the mixing process to the actual maximum distance.

[0020] The mixing zone coefficient is determined based on the ratio of the actual mixing area to the theoretical mixing area of ​​the mixing plane.

[0021] According to an embodiment of the present invention, determining the distance correction factor based on the ratio of the theoretical maximum distance traveled by the airflow during the mixing process to the actual maximum distance includes:

[0022] The furthest mixing point is determined by the extension lines of the edge blades of each of the two adjacent blade arrays;

[0023] The theoretical maximum distance is determined based on the distance between the farthest mixing point and the mixer structure;

[0024] The actual maximum distance is determined based on the preset mixer structure and operating distance.

[0025] The distance correction factor is determined based on the ratio of the farthest distance to the total mixing distance.

[0026] According to an embodiment of the present invention, the design method further includes:

[0027] The estimated actual mixing efficiency of each mixer structure is obtained based on the mixing coefficient and mixing efficiency calculation model of each mixer structure.

[0028] According to an embodiment of the present invention, the mixing efficiency calculation model is established by measuring the actual mixing efficiency results of multiple mixer structures and the mixing coefficient calculation results.

[0029] According to an embodiment of the present invention, the design method further includes:

[0030] Based on the premise that the blade tilt direction and blade array size remain unchanged in the target mixer structure, multiple target mixer structures with different blade spacings are designed.

[0031] Calculate the percentage of airflow area for multiple target mixer structures with different blade spacings;

[0032] The target blade spacing of the target mixer structure is determined based on the percentage of airflow area.

[0033] According to an embodiment of the present invention, the percentage of airflow area is obtained by calculating the ratio of the airflow area of ​​the mixer structure without blades to the airflow area with blades.

[0034] According to an embodiment of the present invention, the calculation method further includes:

[0035] Based on the premise that the blade spacing and blade array size remain unchanged in the target mixer structure, multiple target mixer structures with different blade tilt directions are designed.

[0036] Calculate the mixing coefficients of multiple target mixer structures with different blade tilt directions;

[0037] The target blade tilt direction of the target mixer structure is determined based on the mixing coefficient of multiple target mixer structures with different blade tilt directions.

[0038] As another aspect of the present invention, the application of the above-described mixer structure screening method in the design or optimization of enthalpy difference chamber mixers is also provided.

[0039] According to embodiments of the present invention, the method can obtain multiple mixing planes of the mixer structure based on the design of the mixer structure. Then, considering the zoning correction coefficient, distance correction coefficient, and mixing area coefficient of each mixing plane, the method takes into account air distribution on both sides of the mixing plane, the influence of mixing distance, and the relationship between the actual and theoretical mixing areas. This allows for the calculation of a mixing coefficient that represents the uniformity of airflow mixing, thereby systematically evaluating the mixing effect of each mixer structure to represent the uniformity of airflow mixing. Therefore, it can provide guidance for the design of mixer structures, greatly simplifying the mixer design process. It enables a relatively accurate evaluation of the mixing effect of the mixer without experimental testing, saving significant time and resources and avoiding aimless trial-and-error optimization. Attached Figure Description

[0040] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0041] Figure 1 This is a schematic diagram of the mixer structure design method according to an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the structure of multiple mixers according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram showing the actual mixing area, theoretical mixing area, and theoretical mixing distance in an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the test bench for the mixer structure according to an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the temperature mode of the test bench for the mixer structure according to an embodiment of the present invention;

[0046] Figure 6 This is a fitting graph of the mixing coefficient and actual mixing efficiency in an embodiment of the present invention;

[0047] Figure 7 This is a schematic diagram showing the structural features and dimensions of the mixer according to an embodiment of the present invention;

[0048] Figure 8 This is a schematic diagram of the optimized blade structure according to an embodiment of the present invention;

[0049] Figure 9 This is a graph showing the percentage change in airflow area for the optimized blade structure in an embodiment of the present invention.

[0050] Figure 10 This is a schematic diagram of an optimized structure 14 according to an embodiment of the present invention;

[0051] In the attached diagram:

[0052] 1-Electric heater;

[0053] 2-Air duct;

[0054] 3-Mixed flow pipe section;

[0055] 4-Thermocouple mesh;

[0056] 5-Mixer structure;

[0057] 6- Duct connection points;

[0058] 7-Static pressure hole;

[0059] 8-Main body of the air intake chamber;

[0060] 9-Differential pressure transmitter. Detailed Implementation

[0061] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0062] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "comprising" as used herein indicates the presence of features, steps, or operations, but does not exclude the presence or addition of one or more other features.

[0063] When using expressions such as "at least one of A, B, and C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). When using expressions such as "at least one of A, B, or C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0064] In realizing the concept of this invention, it was discovered that many scholars have used electric heating instead of actual heat exchange samples in their testing methods for mixer performance. By replacing the condenser heat exchange process with electric heating and adjusting the heating power, the air temperature distribution after heat exchange in different samples can be simulated, accelerating the mixer testing process. It was also found that mixing is most difficult when the hot and cold airflows are symmetrically distributed and have the same proportion. Regarding the evaluation of mixer performance, some scholars have used thermocouple temperature grids, arranging temperature grids before and after mixing, calculating the standard deviation of the temperature before and after mixing using the temperature grid measurements, and then using this to calculate and represent the mixer's mixing efficiency.

[0065] However, mixer structures are diverse, and conducting simulation experiments or real-world tests of their mixing efficiency using Fluent requires a significant amount of time, resulting in substantial resource waste during the trial-and-error process. Therefore, this invention proposes a design method for mixer structures based on the mixing principle.

[0066] Specifically, according to one embodiment of the present invention, a method for designing a mixer structure is provided, such as... Figure 1 As shown, the following operations S101 to S105 are included:

[0067] Operation S101: Design multiple mixer structures, wherein the mixer structure includes multiple mixing zones configured with blade arrays, and the multiple blade arrays are tilted in different directions relative to each other.

[0068] According to embodiments of the present invention, a blade array refers to a combination of blades arranged in a certain order in a mixer. These blades can be fixed or adjustable, and their function is to guide and adjust the flow direction and velocity of the fluid to promote mixing between fluids. The tilt direction refers to the deflection angle of the blades relative to a reference direction (such as the inlet direction). In the design of the mixer structure, different blade arrays have different tilt directions, meaning their deflection angles vary. This design can increase the turbulence of the fluid and improve mixing efficiency. Changes in the tilt direction can affect the flow path and mixing mode of the fluid.

[0069] Figure 2 This is a schematic diagram of the structure of multiple mixers according to an embodiment of the present invention.

[0070] In some specific embodiments of the present invention, multiple mixer structures can be designed using computer simulation methods, such as... Figure 2 Structures 1 to 13 are shown in the diagram.

[0071] Furthermore, the blades in each blade array are tilted in the same direction, while the tilting directions of different blade arrays are different.

[0072] Operation S102: Determine multiple mixing planes for each mixer structure, wherein the mixing planes are determined based on the interfaces formed by airflows passing through multiple adjacent blade arrays.

[0073] According to embodiments of the present invention, the interface refers to the boundary where different airflows meet. These interfaces are formed on the mixing plane and are the specific locations where airflow mixing occurs. The mixer structure divides the airflow into different regions through various blade arrays. Due to the inconsistent guiding directions of different blade arrays, the flow directions of the airflow in different regions are inconsistent, thereby generating stronger turbulence and stronger shearing between airflows, enhancing energy transfer between airflows, and thus enabling rapid airflow mixing. The mixing plane is determined based on the interface formed by airflows passing through multiple adjacent blade arrays. It can be understood that each set of multiple adjacent blade arrays generates airflows in different directions, and the interface between these airflows is the mixing plane.

[0074] In some specific embodiments of the present invention, the mixing plane is determined according to the structure of adjacent blade arrays and is related to the mixing distance. The mixing plane is only the area where the airflow can contact each other or has a tendency to contact each other after passing through the mixing structure, rather than an infinitely extending plane.

[0075] Operation S103: Determine the partition correction coefficient, distance correction coefficient, and mixing region coefficient for each mixing plane. The partition correction coefficient is used to characterize the airflow volume relationship of the multiple airflows forming the mixing plane. The distance correction coefficient is used to characterize the relationship between the theoretical maximum distance and the actual maximum distance traveled by the multiple airflows during the mixing process. The mixing region coefficient is used to characterize the relationship between the theoretical mixing area and the actual mixing area of ​​the mixing plane.

[0076] According to an embodiment of the present invention, the partition correction coefficient is used to characterize the airflow volume relationship of the multiple airflows forming the mixing plane. This coefficient is a dimensionless ratio that reflects the relative size or proportion of different airflows in the mixing plane. By calculating the volume of each airflow, it can also be compared with the total volume to obtain the contribution of each airflow to the overall mixing process.

[0077] According to an embodiment of the present invention, the theoretical maximum distance is the furthest distance that multiple airflows can mix, obtained from the results of adjacent blade arrays in the mixer structure. This distance is only related to the mixer structure design itself and is not related to other parameters used during operation. The actual maximum distance can be determined based on the usage of the mixer structure, for example, the actual usage distance of the mixer structure is 5 meters, 10 meters, etc. The distance correction factor is used to characterize the relationship between the theoretical maximum distance and the actual maximum distance traveled by multiple airflows during the mixing process. This factor takes into account the deviation between the actual flow path of the airflow in the mixer and the ideal or theoretical path. By comparing the actual flow distance of the airflow with the theoretically calculated distance, the distance correction factor can quantify the efficiency and possible energy loss of the airflow during the mixing process, thereby optimizing the design of the mixer.

[0078] According to embodiments of the present invention, the theoretical mixing area refers to the area of ​​the interfaces between multiple airflows in different directions generated by adjacent blade arrays, while the actual mixing area refers to the area of ​​the region where multiple airflows actually mix at the airflow interfaces. The region mixing coefficient refers to the relationship between the theoretical mixing area and the actual mixing area. The region mixing coefficient can be used to evaluate whether the design of adjacent blade arrays of the mixer can achieve a good mixing effect. It can be expressed as a ratio. For example, if the actual mixing area is close to the theoretical mixing area, it can be proven that the design of multiple adjacent blade arrays can mix multiple airflows to a large extent.

[0079] Operation S104: Based on the partition correction coefficient, distance correction coefficient and mixing region coefficient of each mixing plane of each mixer structure, the mixing coefficient of each mixer structure is calculated. The mixing coefficient is used to characterize the mixing effect of airflow through the mixer structure.

[0080] According to embodiments of the present invention, the mixing coefficient is a comprehensive parameter used to characterize the mixing effect of airflow through the mixer structure. The mixing coefficient provides an overall evaluation, illustrating the performance of the mixer structure in practical applications; a higher mixing coefficient means a better airflow mixing effect. Each mixing plane has its own zone correction coefficient, distance correction coefficient, and mixing area coefficient, thus each mixing plane has a mixing coefficient. Based on the individual mixing coefficients of each mixing plane in a mixer structure, the mixing coefficient of the mixer structure can be obtained comprehensively, thereby evaluating the mixing effect of the mixer structure.

[0081] Operation S105: Determine the target mixer structure from multiple mixer structures based on the mixing coefficient of each mixer structure.

[0082] According to an embodiment of the present invention, by calculating the mixing coefficient of each mixer structure, the mixing effect of each mixer structure can be determined based on the magnitude of the mixing coefficient, which can also represent the mixing efficiency of the mixer structure, thereby selecting the target mixer structure.

[0083] According to embodiments of the present invention, the method of the present invention can obtain multiple mixing planes of the mixer structure based on the design of the mixer structure, and then calculate the mixing coefficient based on multiple parameters of the mixing planes, thereby systematically evaluating the mixing effect of each mixer structure. This provides guidance for the design of mixer structures, greatly facilitating the mixer design process. It enables a relatively accurate evaluation of the mixing efficiency of the mixer without conducting experiments, saving significant time and resources and avoiding aimless trial-and-error optimization.

[0084] According to an embodiment of the present invention, each mixer structure includes m vertical mixing planes and n horizontal mixing planes among its multiple mixing planes, and operation S104 further includes the following operations S201 to S205:

[0085] Operation S201: Determine the mixing coefficient of each vertical mixing plane based on its respective partition correction coefficient, distance correction coefficient, and mixing area coefficient;

[0086] Operation S202: Determine the vertical mixing coefficient based on the mixing coefficients of each of the m vertical mixing planes;

[0087] Operation S203: Determine the mixing coefficient of each horizontal mixing plane based on its respective partition correction coefficient, distance correction coefficient, and mixing area coefficient;

[0088] Operation S204: Determine the horizontal mixing coefficient based on the mixing coefficients of each of the n horizontal mixing planes;

[0089] Operation S205: Obtain the mixing coefficient of each mixer structure based on the vertical mixing coefficient and the horizontal mixing coefficient.

[0090] According to embodiments of the present invention, the interface for mixing can be generated considering only the vertical and horizontal directions. Due to the differences in the mixer structure, each mixer structure can have multiple vertical mixing planes in the vertical direction and multiple horizontal mixing planes in the horizontal direction.

[0091] According to an embodiment of the present invention, in operations S201 to S202, by calculating the mixing coefficients of m vertical mixing planes, the vertical mixing coefficient of the entire mixer structure can be obtained by averaging.

[0092] According to an embodiment of the present invention, in operations S203 to S204, by calculating the mixing coefficients of n horizontal mixing planes, the horizontal mixing coefficient of the entire mixer structure can be obtained by averaging.

[0093] According to an embodiment of the present invention, in operation S205, the mixing coefficient of the mixer structure can be obtained by summing the horizontal mixing coefficient and the vertical mixing coefficient, or by considering them separately in the two directions, or by setting weights.

[0094] In some specific embodiments of the present invention, the vertical mixing coefficient and the horizontal mixing coefficient are calculated as shown in the following equations (1) and (2):

[0095] (1)

[0096] (2)

[0097] In equations (1) and (2), the subscript p represents the vertical direction, the subscript h represents the horizontal direction, β represents the mixing coefficient, α represents the regional correction coefficient of the m-th vertical mixing plane or the regional correction coefficient of the n-th horizontal mixing plane, γ represents the distance correction coefficient, A2 represents the actual mixing area, and A1 represents the theoretical mixing area.

[0098] According to an embodiment of the present invention, determining the partition correction coefficient for each mixing plane includes: determining the partition correction coefficient based on the area ratio of each of two adjacent blade arrays.

[0099] According to an embodiment of the present invention, when the direction and volume of the airflow are the same for each blade array of the mixer structure, the area of ​​the regions of two adjacent blade array structures on both sides of the mixing plane can represent the volume ratio of the airflow.

[0100] In some specific embodiments of the present invention, the partition correction coefficient of each mixing plane is calculated by equation (3):

[0101] (3)

[0102] In equation (3), α is the partition correction coefficient, A s For the smaller structural area in two adjacent blade arrays, A b The larger structural area is between two adjacent blade arrays.

[0103] According to an embodiment of the present invention, determining the distance correction factor for each mixing plane includes: determining the distance correction factor based on the ratio of the theoretical maximum distance traveled by the airflow during the mixing process to the actual maximum distance.

[0104] Figure 3This is a schematic diagram showing the actual mixing area, theoretical mixing area, and theoretical mixing distance in an embodiment of the present invention.

[0105] In some specific embodiments of the present invention, such as Figure 3 As shown, determining the distance correction factor includes:

[0106] The furthest mixing point is determined by the extension lines of the edge blades of each of the two adjacent blade arrays;

[0107] The theoretical maximum distance is determined based on the distance between the farthest mixing point and the mixer structure;

[0108] The actual maximum distance is determined based on the preset mixer structure and operating distance.

[0109] The distance correction factor is determined based on the ratio of the farthest distance to the total mixing distance.

[0110] According to an embodiment of the present invention, the farthest mixing point is the farthest point that the blade array on both sides of the mixing plane can act on, and it can be determined by the extension line of the outermost blade in the blade array.

[0111] For example, such as Figure 3 As shown, the farthest mixing point is obtained by extending the outermost blades on both sides of the adjacent interface, or it can be understood as extending the "most unfavorable" interface point between the opposite blades. This is based on the distance D from the mixing point to the mixer structure. x As the theoretical maximum distance.

[0112] According to an embodiment of the present invention, the actual maximum distance is the distance between the airflow inlet of the mixer structure and the outlet of the ventilation duct section in a specific application scenario such as a ventilation duct section, which can also be understood as the total mixing distance.

[0113] In some specific embodiments of the present invention, the distance correction coefficient is calculated by the following formula (4):

[0114] (4)

[0115] In equation (4), γ is the distance correction coefficient, and D x For the theoretical maximum distance, D m This represents the actual farthest distance.

[0116] According to an embodiment of the present invention, determining the mixing region coefficient of each mixing plane includes: determining the mixing region coefficient based on the ratio of the actual mixing area to the theoretical mixing area of ​​the mixing plane.

[0117] According to an embodiment of the present invention, the relationship between the actual mixing area and the theoretical mixing area can be represented by a ratio method.

[0118] For example, such as Figure 3 As shown, the rectangle formed by the green and black areas is constructed through the airflow interface of two adjacent blade arrays, using the farthest mixing point and the length of the mixer structure. This rectangle, representing the theoretical mixing area, can be understood as the area of ​​the interface where mixing would theoretically occur. Furthermore, due to the actual influence of the blade array, no two airflows mix in the black area; therefore, the area of ​​the green area represents the actual mixing area. By calculating the ratio of the actual mixing area to the theoretical mixing area, the mixing region coefficient can be obtained.

[0119] According to an embodiment of the present invention, a mixing efficiency calculation model is established by measuring the actual mixing efficiency results of multiple mixer structures and the mixing coefficient calculation results.

[0120] According to an embodiment of the present invention, the actual mixing efficiency is a numerical value of the actual mixing effect of the mixer on the airflow, measured by methods such as experiments. The mixing efficiency calculation model is a relationship model between the actual mixing efficiency and the mixing coefficient, and the calculated value of the actual mixing efficiency can be obtained by calculating the mixing coefficient and the mixing efficiency calculation model.

[0121] Figure 4 This is a schematic diagram of the test bench for the mixer structure according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the temperature mode of the test bench for the mixer structure in an embodiment of the present invention.

[0122] In some specific embodiments of the present invention, the actual mixing efficiency is determined by, for example... Figure 4 The device shown was tested. After being heated by the electric heater 1, the airflow entered the mixing pipe section 3 through the air duct 2. Thermocouple mesh 4 was installed at both ends of the mixing pipe section 3 to measure the inlet and outlet air temperatures of the mixing pipe section 3. The mixing device structure 5 was installed downstream of the thermocouple mesh 4 at the air inlet of the mixing pipe section 3.

[0123] For example, with Figure 2 Taking structure 1 as an example, the mixing coefficients of structure 1 in the vertical and horizontal directions are calculated using equations (1) and (2):

[0124]

[0125] =(97.5×(1-250 / 500)×(1+1) / 2×4) / 4=0.4875

[0126] Among them, through Figure 3 The plane shown can be directly calculated to obtain A. 2h1 / A 2h1 =97.5, γ 1h =1-(D x / tan(θ)) / D m=(1-250 / 500) is the distance correction factor, reflecting the limitation of the mixing distance on turbulence development, D m Selection such as Figure 4 As shown, the length of the mixing pipe section 3 is D. m α 1h =A s / A b Since the mixing structures on both sides of the interface of structure 1 are consistent, α 1h =1; furthermore, structure 1 lacks a vertical mixing interface, therefore β is considered to be... p =0.

[0127] The mixed-flow systems of structures 1 to 13 are calculated using equations (1) and (2), and... Figure 4 The device shown and Figure 5 The results of the actual mixing efficiency measured in temperature mode are shown in Table 1 below:

[0128] Table 1

[0129]

[0130] According to an embodiment of the present invention, it can be seen from Table 1 that structure 13 has a high mixing coefficient in both the vertical and horizontal directions, and also has a high actual mixing efficiency in both directions. Therefore, it can be shown that the calculated mixing coefficient can characterize the change in actual mixing efficiency. At the same time, it can be determined that among structures 1 to 13, structure 13 is the target mixer structure.

[0131] According to an embodiment of the present invention, the estimated actual mixing efficiency of each mixer structure is obtained based on the mixing coefficient and mixing efficiency calculation model of each mixer structure.

[0132] According to an embodiment of the present invention, by calculating the mixing coefficient of multiple mixer structures and measuring the actual mixing efficiency, a linear relationship between the mixing coefficient and the actual mixing efficiency can be obtained. Thus, the estimated value of the actual mixing efficiency can be obtained directly by calculating the mixing efficiency, without the need to perform actual measurements on each mixer structure each time.

[0133] For example, by linearly fitting the calculated mixing coefficients of the mixer structures 1 to 13 in Table 1 with the actual measured mixing efficiency results, the results... Figure 6 As shown.

[0134] Figure 6 This is a fitting graph of the mixing coefficient and the actual mixing efficiency in an embodiment of the present invention.

[0135] according to Figure 6It can be seen that the trend of the mixing coefficient is basically consistent with the actual mixing efficiency. Therefore, the actual mixing efficiency can be estimated by establishing a mixing efficiency calculation model.

[0136] Furthermore, the mixing efficiency calculation model can be obtained as shown in equations (5), (6), and (7):

[0137] (5);

[0138] (6);

[0139] (7).

[0140] In equations (5), (6), and (7), E' represents the estimated actual mixing efficiency, β represents the mixing coefficient, and the subscript p indicates the vertical direction. Simultaneously, the estimated actual mixing efficiency in the horizontal direction can also be calculated using equations (5), (6), and (7).

[0141] According to embodiments of the present invention, the blades in each blade array have the same tilt direction and the same spacing between the blades. Changing the tilt direction and spacing of the blades may affect the mixing efficiency. Based on the determined mixer structure, i.e., the blade array size, other parameters of the mixer structure can be optimized.

[0142] Furthermore, while maintaining good mixing efficiency, it is necessary to further analyze the pressure drop loss caused by the mixer structure. Excessive pressure drop in the mixer structure will lead to a higher operating frequency of the enthalpy difference chamber fan at the same airflow rate, resulting in higher energy consumption and negatively impacting the creation of the enthalpy difference chamber's ambient temperature. Therefore, it is necessary to minimize the mixing pressure drop as much as possible while ensuring mixing efficiency, and further optimize the mixer structure.

[0143] According to an embodiment of the present invention, the design method of the mixer structure further includes:

[0144] Based on the premise that the blade tilt direction and blade array size remain unchanged in the target mixer structure, multiple target mixer structures with different blade spacings are designed.

[0145] Calculate the percentage of airflow area for multiple target mixer structures with different blade spacings;

[0146] The target blade spacing of the target mixer structure is determined based on the percentage of airflow area.

[0147] In some specific embodiments of the present invention, the airflow area percentage is obtained by calculating the ratio of the airflow area of ​​the mixer structure without blades to the airflow area with blades. The airflow area percentage is a parameter for measuring the airflow efficiency in the mixer structure. The airflow area after adding blades can be calculated by multiplying the vertical distance between the blades by their height.

[0148] According to an embodiment of the present invention, without changing the blade tilt direction and the size of the blade array, the blade spacing of the blade array is optimized by controlling a single variable to change only the blade spacing of the mixer structure and calculating the percentage of airflow area.

[0149] In some specific embodiments of the present invention, the influence of the blade structure on the mixing efficiency and pressure drop can also be optimized by changing the blade structure.

[0150] Figure 7 This is a schematic diagram showing the structural features and dimensions of the mixer according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the optimized blade structure according to an embodiment of the present invention; Figure 9 This is a graph showing the percentage change in airflow area for the optimized blade structure in an embodiment of the present invention.

[0151] Among them, Figure 7 In the diagram, D3 represents the spacing between adjacent blades, Dt represents the thickness of the mixer, Dn and Dy represent the blade array size, and Dh represents the width of the mixer.

[0152] exist Figure 7 and Figure 8 In the diagram, D1 and D2 represent the feature dimensions of the improved blade in the orthographic projection direction of the blade array.

[0153] according to Figure 7 , Figure 8 and Figure 9 It can be seen that when the blade spacing D3 is kept consistent with D1, the mixing efficiency remains unchanged. However, due to the bending of the blades, the flow area of ​​the mixer is increased, which can effectively reduce the mixing pressure drop. Considering the influence of the mixing blade thickness, keeping D1 and D3 consistent as variables, we can derive D1 and D3 that maximize the flow area.

[0154] It can be seen that, for example, when Dh is 500mm, the optimal flow area percentage is approximately 45.53% when D1(D3) = 0.036Dh or 18mm, while it is 45.03% when D1(D3) = 0.05Dh or 25mm, with a difference of only 1.1%. Considering lightweight design and ease of processing, the final design size of D1(D3) is 0.05Dh. The optimized structure is structure 14. Structure 14 has a mixing efficiency of 89% and a pressure drop of 330Pa, while structure 13 has a mixing efficiency of 90% and a pressure drop of 550Pa. That is, structure 14 reduces the pressure drop by 40% while maintaining the same mixing efficiency, illustrating the influence of the flow area percentage on the mixing pressure drop. This also supplements the lack of consideration for blade spacing in the estimated mixing efficiency proposed in this invention.

[0155] According to embodiments of the present invention, multiple target mixer structures with different blade tilt directions can be designed while keeping the blade spacing and blade array size unchanged in the target mixer structure.

[0156] Calculate the mixing coefficients of multiple target mixer structures with different blade tilt directions;

[0157] The target blade tilt direction of the target mixer structure is determined based on the mixing coefficient of multiple target mixer structures with different blade tilt directions.

[0158] Figure 10 This is a schematic diagram of an optimized scheme for structure 14 in an embodiment of the present invention.

[0159] In some specific embodiments of the present invention, taking structure 14 as an example, such as... Figure 10 As shown, using the proposed mixing coefficient, the mixing efficiency is analyzed for different mixing ratio regions, different mixer thicknesses, and different blade angles, where D... n and D y This can represent the proportion of different blade array regions in structure 14, i.e., the blade array size, D. t It can represent the thickness of the mixer structure.

[0160] like Figure 10As shown, based on the optimization of schemes A (including schemes A1~A7), B (including schemes B1~B7), X (including schemes X1~X5), Y (including schemes Y1~Y3), and Z (including schemes Z1~Z3), the blade structure is modified to ensure that the function of the outer ring baffle blades remains consistent when the mixer structure changes. The blades in section D1 are meaningless for improving mixing efficiency. Based on the above theoretical optimization and improvement, the final scheme Y1 is obtained. In order to achieve lightweight design, the thickness is reduced to restore the initial blade structure, while the range of the outer ring baffle is increased to offset the impact of the thickness reduction. According to the mixing coefficient calculation method of this invention, its mixing coefficient is 54, consistent with structure 13. After Fluent simulation, the mixing efficiency is 89% and the pressure drop is 367 Pa, which further demonstrates the effectiveness of the design method proposed in this invention.

[0161] The results are shown in Tables 2 to 6.

[0162] Table 2

[0163]

[0164] Table 3

[0165]

[0166] Table 4

[0167]

[0168] Table 5

[0169]

[0170] Table 6

[0171]

[0172] As can be seen from Tables 2 to 6, by optimizing the thickness, blade angle, and blade array size of the mixer structure, calculating the mixing coefficient to obtain the estimated mixing efficiency, and then performing actual measurements of the mixing efficiency, the mixing structure can be optimized to obtain the trend of mixing efficiency and mixing pressure drop after the structure is changed, which greatly saves development and experimental costs.

[0173] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A design method for a mixer structure, comprising: Design multiple mixer structures, wherein the mixer structure includes multiple mixing zones configured with blade arrays, and the multiple blade arrays are tilted in different directions relative to each other; Multiple mixing planes are determined for each of the mixer structures, wherein the mixing planes are determined based on the interfaces formed by airflows passing through the adjacent multiple blade arrays; Each of the mixing planes is determined by a partition correction coefficient, a distance correction coefficient, and a mixing region coefficient. The partition correction coefficient is used to characterize the airflow volume relationship of the multiple airflows forming the mixing plane. The distance correction coefficient is used to characterize the relationship between the theoretical maximum distance and the actual maximum distance traveled by the multiple airflows during the mixing process. The mixing region coefficient is used to characterize the relationship between the theoretical mixing area and the actual mixing area of ​​the mixing plane. The mixing coefficient of each mixer structure is calculated based on the partition correction coefficient, the distance correction coefficient, and the mixing region coefficient of each of the plurality of mixing planes of each mixer structure, wherein the mixing coefficient is used to characterize the mixing effect of the mixer structure; A target mixer structure is determined from the plurality of mixer structures based on the mixing coefficient of each mixer structure.

2. The design method according to claim 1, wherein, Each of the multiple mixing planes in the mixer structure includes m vertical mixing planes and n horizontal mixing planes; The calculation of the mixing coefficient of each mixer structure based on the partition correction coefficient, the distance correction coefficient, and the mixing region coefficient of each of the plurality of mixing planes of each mixer structure includes: The mixing coefficient of each vertical mixing plane is determined based on its respective partition correction coefficient, distance correction coefficient, and mixing region coefficient. The vertical mixing coefficient is determined based on the mixing coefficient of each of the m vertical mixing planes; The mixing coefficient of each horizontal mixing plane is determined based on its respective partition correction coefficient, distance correction coefficient, and mixing region coefficient. The horizontal mixing coefficient is determined based on the mixing coefficient of each of the n horizontal mixing planes. The mixing coefficient of each of the mixer structures is obtained based on the vertical mixing coefficient and the horizontal mixing coefficient.

3. The design method according to claim 1, wherein, The determination of the partition correction coefficient, distance correction coefficient, and mixing region coefficient for each of the mixing planes includes: The partition correction coefficient is determined based on the area ratio of each of the two adjacent blade arrays; The distance correction coefficient is determined based on the ratio of the theoretical maximum distance traveled by the airflow during the mixing process to the actual maximum distance. The mixing region coefficient is determined based on the ratio of the actual mixing area to the theoretical mixing area of ​​the mixing plane.

4. The design method according to claim 3, wherein, The determination of the distance correction coefficient based on the ratio of the theoretical maximum distance traveled by the airflow during the mixing process to the actual maximum distance includes: The farthest mixing point is determined based on the extension lines of the edge blades of each of the two adjacent blade arrays; The theoretical maximum distance is determined based on the distance between the farthest mixing point and the mixer structure; The actual maximum distance is determined based on the preset mixer structure and the distance used. The distance correction coefficient is determined based on the ratio of the farthest distance to the total mixing distance.

5. The design method according to claim 1, wherein, The design method further includes: The estimated actual mixing efficiency of each mixer structure is obtained based on the mixing coefficient and mixing efficiency calculation model of each mixer structure.

6. The design method according to claim 5, wherein, The mixing efficiency calculation model is established by measuring the actual mixing efficiency of multiple mixing device structures and the mixing coefficient calculation results.

7. The design method according to claim 1, wherein, The design method further includes: Based on the fact that the blade tilt direction and blade array size remain unchanged in the target mixer structure, multiple target mixer structures with different blade spacings are designed. Calculate the percentage of airflow area for each of the target mixer structures with different blade spacings; The target blade spacing of the target mixer structure is determined based on the percentage of the airflow area.

8. The design method according to claim 7, wherein, The percentage of airflow area is obtained by calculating the ratio of the airflow area of ​​the mixer structure without blades to the airflow area with blades.

9. The design method according to claim 1, wherein, The design method further includes: Based on the premise that the blade spacing and blade array size remain unchanged in the target mixer structure, multiple target mixer structures with different blade tilt directions are designed. Calculate the mixing coefficients of the multiple target mixer structures with different blade tilt directions; The target blade tilt direction of the target mixer structure is determined based on the mixing coefficient of multiple target mixer structures with different blade tilt directions.

10. The application of a design method for a mixer structure as described in any one of claims 1 to 9 in the design or optimization of enthalpy difference chamber mixers.

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