Design method and product for uniform air outlet of equal-section multi-air outlet air duct

Abstract

The present invention discloses a uniform air outlet design method and product for an air outlet duct with equal cross-section and multiple air outlets. For an air outlet duct with equal cross-section and multiple air outlets, the air outlet duct is equally divided into a plurality of small sections of the air outlet duct. The air outlet area of ​​each small section of the air outlet duct is designed so that the air outlet flow rate of each small section of the air outlet duct is equal, thereby achieving uniform air outlet: assuming that the total length of the air outlet duct is L, the width is B, and the height is H, the air outlet duct is equally divided into n small sections and n≥2, that is, the length L1 of each small section of the air outlet duct is L / n, according to the air supply direction, the air outlet area F1 of the first small section of the air outlet duct is first determined, and then according to the calculation formula F （i+1） =(B*H*F i ) / ((2*n‑2)*F i 2 +B 2 *H 2 ) 0.5 Calculate the outlet area of ​​the next small section of the outlet duct in sequence, where F i and F （i+1） The air outlet area of ​​the i-th air outlet duct and the air outlet area of ​​the i+1-th air outlet duct are calculated respectively, until the air outlet areas of all the air outlet ducts are calculated. This method does not require additional hardware investment and the calculation method is simple.

Description

Technical Field

[0001] The present invention belongs to the field of ventilation technology, and in particular relates to a uniform air outlet design method and product for an air outlet duct with equal cross-section and multiple air outlets. Background Art

[0002] Ventilation ducts are responsible for the transmission and distribution of air. Currently, the air outlets on the air outlet ducts are generally of the same size, and are either installed with mesh plates or designed in a trapezoidal shape. As the air volume is gradually diverted, the air outlet is not uniform. In order to achieve uniform air outlet, air valves are currently installed at the air outlets to change the air flow rate of the air outlets. Since the air outlets are of the same size, uniform air outlet can be achieved by controlling the air flow rate of each air outlet to be the same. This method not only requires the addition of air valves, but also requires the addition of wind speed measuring components for measuring wind speed, which requires a large hardware investment. Summary of the invention

[0003] The purpose of the present invention is to provide a method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets, and a product obtained by the design. The method does not require additional hardware investment and the calculation method is simple.

[0004] The technical solution adopted by the present invention is:

[0005] A method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets is provided. For an air outlet duct with equal cross-section and multiple air outlets, the air outlet duct is equally divided into several small sections. The air outlet area of ​​each small section of the air outlet duct is designed so that the air outlet flow rate of each small section of the air outlet duct is equal, thereby achieving uniform air outlet: assuming that the total length of the air outlet duct is L, the width is B, and the height is H, the air outlet duct is equally divided into n small sections and n≥2, that is, the length of each small section of the air outlet duct L1=L / n, according to the air supply direction, the air outlet area F1 of the first small section of the air outlet duct is first determined, and then according to the calculation formula F （i+1） =(B*H*F i ) / ((2*n-2)*F i 2 +B 2 *H 2 ) 0.5 Calculate the outlet area of ​​the next small section of the outlet duct in sequence, where F i and F （i+1） are the air outlet area of ​​the i-th small air outlet duct section and the air outlet area of ​​the i+1-th small air outlet duct section respectively, where i is an integer ≥1 and ≤n-1, until the air outlet areas of all small air outlet duct sections are calculated.

[0006] Further, when determining the air outlet area F1 of the first small section of the air outlet duct, the air outlet area F1 of the first small section of the air outlet duct cannot exceed the area of ​​the small section of the air outlet duct, that is, F1≤B*L1.

[0007] Furthermore, if there is a minimum wind speed requirement, when determining the outlet area F1 of the first small section of the outlet duct, the outlet wind speed V1 of the first small section of the outlet duct cannot be less than the required minimum wind speed requirement V min , that is, V1=A / (n*F1)≥V min , where A is the total air supply volume of the air outlet duct.

[0008] As a first solution, for each small section of the air outlet duct, the air outlet is a centralized single opening.

[0009] As a second solution, for each small section of the air outlet duct, the air outlet is provided with a plurality of evenly arranged distributed openings.

[0010] As a third solution, for each small section of the air outlet duct, a portion of the air outlets adopts a centralized single opening, and another portion of the air outlets adopts a distributed plurality of evenly arranged openings.

[0011] An air outlet duct is obtained by adopting the above-mentioned uniform air outlet design method for an air outlet duct with equal cross-section and multiple air outlets.

[0012] As the first solution, the air outlet duct is used in the drying room for agricultural products. The heating equipment outside the drying room sends the heated hot air into the drying room through the air outlet duct. The air outlet duct evenly sends the hot air to various positions in the drying room to ensure that the agricultural products can be evenly dehydrated during the drying process. In addition, the number of equal parts of the air outlet duct is selected according to the requirements of the drying room for air supply uniformity. The more equal parts of the air outlet duct, the more uniform the air supply, and the smaller the total air supply required to dry the same amount of agricultural products.

[0013] As the second solution, the air outlet duct is used in a large space venue with a long air supply distance and a minimum wind speed requirement. First, the air outlet duct is set according to the distribution of the venue plane and the number of equal parts of the air outlet duct is determined. Then, the air outlet area F1 of the first small section of the air outlet duct is determined, so that the air outlet wind speed V1 of the first small section of the air outlet duct is not lower than the minimum wind speed requirement V min To ensure that the air volume of each small section of the air outlet duct is uniform and the air speed at the air outlet is not lower than the minimum wind speed requirement V min .

[0014] The beneficial effects of the present invention are:

[0015] The method can achieve uniform air outlet only by designing the air outlet area of ​​each small section of the air outlet duct, without increasing hardware investment; the key is that the calculation method adopted by the method is simple, and only a few parameters need to be determined to quickly calculate the air outlet area of ​​each small section of the air outlet duct to obtain a complete design scheme; and according to the characteristics of the method, the larger the n value, the more uniform the air outlet, so the number of equal parts of the air outlet duct can be determined according to the actual uniformity requirements; and according to the characteristics of the method, the air outlet wind speed of each small section of the air outlet duct gradually increases according to the air supply direction, so the air outlet wind speed V1 of the first small section of the air outlet duct can be controlled by controlling the air outlet area F1 of the first small section of the air outlet duct, thereby ensuring that the minimum wind speed requirement is met. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of an air outlet duct with a medium cross-section and multiple air outlets in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0018] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0019] Embodiment 1

[0020] The present invention discloses a method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets. Figure 1 As shown, the outlet duct is divided into several small sections. By designing the outlet area of ​​each small section of the outlet duct, the air flow rate of each small section of the outlet duct is equal, so as to achieve uniform air outlet: Assume that the total length of the outlet duct is L, the width is B, and the height is H. The outlet duct is divided into n small sections and n ≥ 2, that is, the length of each small section of the outlet duct is L1 = L / n. According to the air supply direction, the outlet area F1 of the first small section of the outlet duct is first determined, and then according to the calculation formula F （i+1） =(B*H*F i ) / ((2*n-2)*F i 2 +B 2 *H 2 ) 0.5 Calculate the outlet area of ​​the next small section of the outlet duct in sequence, where F i and F （i+1）are the air outlet area of ​​the i-th small air outlet duct section and the air outlet area of ​​the i+1-th small air outlet duct section respectively, where i is an integer ≥1 and ≤n-1, until the air outlet areas of all small air outlet duct sections are calculated.

[0021] According to the characteristics of the present method, the total length L, width B, and height H of the air outlet duct are generally quantitative, and the number n of the air outlet ducts can be set according to actual needs. Therefore, determining the air outlet area F1 of the first small section of the air outlet duct is a key step: when determining the air outlet area F1 of the first small section of the air outlet duct, the air outlet area F1 of the first small section of the air outlet duct cannot exceed the area of ​​the small section of the air outlet duct, that is, F1≤B*L1; and, if there is a minimum wind speed requirement, when determining the air outlet area F1 of the first small section of the air outlet duct, the air outlet wind speed V1 of the first small section of the air outlet duct cannot be less than the required minimum wind speed requirement V min , that is, V1=A / (n*F1)≥V min , where A is the total air supply volume of the air outlet duct.

[0022] According to the above scheme, for example, five air outlets are opened at equal intervals in a section of air outlet duct with a cross section of 1500mm*500mm and a length of 10 meters, so that the air volume of the five air outlets is uniform, and the total air volume is 20000m 3 / h, and the wind speed at each outlet is not less than 4m / s, then the design process is:

[0023] The first step is to sort out the known data. It can be known that the total length of the air outlet duct is L=10m, the width is B=1500mm, and the height is H=500mm. The air outlet duct is divided into 5 small sections. The length of each small section of the air outlet duct is L1=2000mm. The total air supply volume of the air outlet duct is A=20000m 3 / h, the ideal air volume of each small section of the air outlet duct is A / 5=4000m 3 / h, minimum wind speed requirement V min =4m / s.

[0024] The second step is to determine the outlet area F1 of the first section of the air duct according to the air supply direction. Here, F1=270000mm 2 ; Meet F1 <B*L1=3000000mm 2 ; The outlet wind speed of the first section of the air outlet duct is V1=A / (n*F1)≈4.12m / s, satisfying V1>V min =4m / s.

[0025] Step 3: Calculate the outlet area of ​​the second section of the air duct F2 = (B*H*F1) / ((2*n-2)*F1) 2 +B 2 *H 2 ) 0.5≈189186mm 2 At this time, the wind speed at the outlet of the second section of the air outlet duct is V2=A / (n*F2)≈5.87m / s, satisfying V2>V min =4m / s.

[0026] Step 4: Calculate the outlet area of ​​the third section of the air outlet duct F3 = (B*H*F2) / ((2*n-2)*F2 2 +B 2 *H 2 ) 0.5 ≈154007mm 2 At this time, the wind speed at the outlet of the third section of the air outlet duct is V3=A / (n*F3)≈7.21m / s, satisfying V3>V min =4m / s.

[0027] Step 5: Calculate the outlet area of ​​the fourth section of the air duct F4 = (B*H*F3) / ((2*n-2)*F3 2 +B 2 *H 2 ) 0.5 ≈133175mm 2 At this time, the wind speed at the outlet of the fourth section of the air outlet duct is V4=A / (n*F4)≈8.34m / s, satisfying V4>V min =4m / s.

[0028] Step 6: Calculate the outlet area of ​​the fifth section of the air duct F5 = (B*H*F4) / ((2*n-2)*F4) 2 +B 2 *H 2 ) 0.5 ≈119009mm 2 At this time, the outlet wind speed of the fifth section of the air outlet duct is V5=A / (n*F5)≈9.34m / s, satisfying V5>V min =4m / s.

[0029] For each small section of the air outlet duct, the air outlet can be set in the following three ways:

[0030] 1) The air outlets are all centralized single openings, see 1 Figure 1 ;

[0031] 2) The air outlets are distributed with multiple evenly arranged openings;

[0032] 3) Some of the air outlets use a centralized single opening, while other air outlets use distributed multiple evenly arranged openings.

[0033] Embodiment 2

[0034] The present embodiment discloses an air outlet duct, which is obtained by adopting the above-mentioned uniform air outlet design method for the air outlet duct with equal cross-section and multiple air outlets. The air outlet duct is used in a drying room for agricultural products. The heating equipment outside the drying room sends the heated hot air into the drying room through the air outlet duct. The air outlet duct evenly sends the hot air to various positions in the drying room to ensure that the agricultural products can be evenly dehydrated during the drying process. In addition, the number of equal parts of the air outlet duct is selected according to the requirements of the drying room for air supply uniformity. The more the number of equal parts of the air outlet duct is, the more uniform the air supply is, and the smaller the total air supply required for drying the same amount of agricultural products is.

[0035] Embodiment 3

[0036] The present embodiment discloses an air outlet duct, which is obtained by adopting the above-mentioned uniform air outlet design method for an air outlet duct with equal cross-section and multiple air outlets. The air outlet duct is applied to large-space venues (swimming pools, gymnasiums, etc.), where the air supply distance is long and there is a minimum wind speed requirement. First, the air outlet duct is arranged according to the distribution of the venue plane and the number of equal divisions of the air outlet duct is determined, and then the air outlet area F1 of the first small section of the air outlet duct is determined, so that the air outlet wind speed V1 of the first small section of the air outlet duct is not lower than the minimum wind speed requirement V min To ensure that the air volume of each small section of the air outlet duct is uniform and the air speed at the air outlet is not lower than the minimum wind speed requirement V min If the traditional hydraulic calculation method is used, it is often necessary to use the assumed flow rate method for complex repeated calculations, which is computationally intensive and difficult to calculate accurately. In the project, the air supply volume can only be increased to meet the minimum air velocity requirement of each air outlet, resulting in uneven air supply and low energy consumption. This method perfectly solves this problem.

[0037] The method can achieve uniform air outlet only by designing the air outlet area of ​​each small section of the air outlet duct, without increasing hardware investment; the key is that the calculation method adopted by the method is simple, and only a few parameters need to be determined to quickly calculate the air outlet area of ​​each small section of the air outlet duct to obtain a complete design scheme; and according to the characteristics of the method, the larger the n value, the more uniform the air outlet, so the number of equal parts of the air outlet duct can be determined according to the actual uniformity requirements; and according to the characteristics of the method, the air outlet wind speed of each small section of the air outlet duct gradually increases according to the air supply direction, so the air outlet wind speed V1 of the first small section of the air outlet duct can be controlled by controlling the air outlet area F1 of the first small section of the air outlet duct, thereby ensuring that the minimum wind speed requirement is met.

[0038] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets, characterized in that: For an outlet duct with equal cross-section and multiple air outlets, divide it into several small sections of outlet duct. By designing the outlet area of ​​each small section of the outlet duct, the air flow rate of each small section of the outlet duct is equal, so as to achieve uniform air outlet: Assume that the total length of the outlet duct is L, the width is B, and the height is H. The outlet duct is divided into n small sections and n ≥ 2, that is, the length of each small section of the outlet duct is L1 = L / n. According to the air supply direction, first determine the outlet area F1 of the first small section of the outlet duct, and then calculate it according to the calculation formula F （i+1） =(B*H*F i ) / ((2*n-2)*F i 2 +B 2 *H 2 ) 0.5 Calculate the outlet area of ​​the next small section of the outlet duct in sequence, where F i and F （i+1） are the outlet areas of the i-th small section of the air outlet duct and the outlet areas of the i+1-th small section of the air outlet duct, respectively, where i is an integer ≥1 and ≤n-1, until the outlet areas of all small sections of the air outlet duct are calculated; when determining the outlet area F1 of the first small section of the air outlet duct, the outlet area F1 of the first small section of the air outlet duct cannot exceed the area of ​​the small section of the air outlet duct, that is, F1≤B*L1; if there is a minimum wind speed requirement, when determining the outlet area F1 of the first small section of the air outlet duct, the outlet wind speed V1 of the first small section of the air outlet duct cannot be less than the required minimum wind speed requirement V min , that is, V1=A / (n*F1)≥V min , where A is the total air supply volume of the air outlet duct.

2. The method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets as claimed in claim 1, characterized in that: For each small section of the air outlet duct, the air outlet is a centralized single opening.

3. The method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets as claimed in claim 1, characterized in that: For each small section of the air outlet duct, the air outlet is a distributed multiple evenly arranged opening.

4. The method for designing uniform air outlet of an air outlet duct with equal cross-section and multiple air outlets as claimed in claim 1, characterized in that: For each small section of the air outlet duct, a portion of the air outlets adopts a centralized single opening, and another portion of the air outlets adopts a distributed plurality of evenly arranged openings.

5. An air outlet duct, characterized in that: The method is obtained by adopting the uniform air outlet design method of the air outlet duct with equal cross-section and multiple air outlets as described in any one of claims 1 to 4.

6. The air outlet duct according to claim 5, characterized in that: The air outlet duct is used in the drying room for agricultural products. The heating equipment outside the drying room sends the heated hot air into the drying room through the air outlet duct. The air outlet duct evenly sends the hot air to various positions in the drying room to ensure that the agricultural products can be evenly dehydrated during the drying process. In addition, the number of equal parts of the air outlet duct is selected according to the requirements of the drying room for air supply uniformity. The more equal parts of the air outlet duct, the more uniform the air supply, and the smaller the total air supply required for drying the same amount of agricultural products.

7. The air outlet duct according to claim 5, characterized in that: The air outlet duct is used in large-space venues. The air supply distance is long and there is a minimum wind speed requirement. First, the air outlet duct is set according to the distribution of the venue plane and the number of equal parts of the air outlet duct is determined. Then, the outlet area F1 of the first small section of the air outlet duct is determined, so that the outlet wind speed V1 of the first small section of the air outlet duct is not lower than the minimum wind speed requirement V min To ensure that the air volume of each small section of the air outlet duct is uniform and the air speed at the air outlet is not lower than the minimum wind speed requirement V min .

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