Air supply system design method, machine-readable storage medium, and processor

Abstract

The application discloses a kind of air supply system design method, machine readable storage medium and processor, method includes: air supply branch pipe arrangement mode and design experience parameter are drafted;Air supply branch pipe nozzle calculation parameter is calculated according to design experience parameter;Air supply branch pipe branch pipe head loss is calculated according to design experience parameter and nozzle calculation parameter;Air supply branch pipe branch pipe static head is calculated according to branch pipe head loss;Static pressure coefficient k is drafted to calculate the branch pipe diameter of air supply branch pipe;When it is judged that the branch pipe diameter is in the range of pre-set allowable diameter, it is determined to use the branch pipe diameter, otherwise, design experience parameter is corrected until the branch pipe diameter is in the range of pre-set allowable diameter.The application can consider the actual factors such as pipeline resistance affecting the uniformity of each nozzle flow in the design process, so that the uniformity of each nozzle flow reaches the preset uniformity requirement when the design result is used, and rapid design can be realized.

Description

Technical Field

[0001] This invention relates to the field of air supply system technology, and more specifically, to an air supply system design method, a machine-readable storage medium, a processor, and a computer program product. Background Technology

[0002] In applications such as air purification and pollutant collection, the higher the homogeneity of the flow field, the lower the probability of pollutant accumulation points forming in enclosed spaces. Therefore, it is necessary to design an air supply system that can ensure uniform air delivery. Currently, the design of air supply systems mainly relies on experience and CFD simulation, which do not adequately consider pipe resistance. This can easily lead to a significant difference between the actual flow distribution and the preset flow distribution in branch pipes, resulting in uneven flow at the branch pipe nozzles and making it difficult to meet the requirements for a highly homogeneous flow field. Summary of the Invention

[0003] In view of at least one of the above-mentioned defects or deficiencies in the prior art, the present invention provides an air supply system design method, a machine-readable storage medium, a processor, and a computer program product, which can take into account the actual factors affecting the flow uniformity of each nozzle, such as pipe resistance, during the design process, so that the flow uniformity of each nozzle reaches the preset uniformity requirement when the design result is adopted, and at the same time, rapid design can be achieved.

[0004] To achieve the above objectives, the first aspect of the present invention provides a method for designing an air supply system, comprising:

[0005] Determine the layout and design parameters of the air supply branch ducts;

[0006] The nozzle calculation parameters of the air supply branch pipe are calculated based on the design experience parameters.

[0007] The branch head loss of the air supply branch pipe is calculated based on the design experience parameters and the nozzle calculation parameters.

[0008] The static pressure head of the air supply branch pipe is calculated based on the branch pipe pressure head loss.

[0009] The diameter of the air supply branch pipe is calculated based on the design experience parameters, the static pressure head of the branch pipe, and the proposed static pressure coefficient k, wherein the static pressure coefficient k is the ratio of the static pressure head to the dynamic pressure head at the inlet of the air supply branch pipe.

[0010] Determine whether the diameter of the branch pipe exceeds the preset allowable diameter range;

[0011] When it is determined that the diameter of the branch pipe is within the preset allowable diameter range, the branch pipe diameter is adopted; otherwise, the design experience parameters are corrected until the diameter of the branch pipe is within the preset allowable diameter range.

[0012] Optionally, the proposed layout and design parameters for the air supply branch ducts include:

[0013] The main air supply pipe is planned to be connected sequentially to an upstream air supply branch pipe and a downstream air supply branch pipe along the airflow direction inside the pipe.

[0014] The total air volume q of the proposed air supply main is determined. t The length L of the air distribution area of ​​each of the upstream and downstream air supply branches, and the penetration depth L of the nozzle jet of the upstream air supply branch. u The penetration depth L of the nozzle jet in the downstream air supply branch pipe b The terminal velocity v of the jet stream from the nozzles of the upstream and downstream air supply branches. jm The jet angle θ of the axisymmetric jets from the nozzles of the upstream and downstream air supply branches, and the nozzle friction length l of the upstream air supply branch. ju The nozzle friction length l of the downstream air supply branch pipe jb The following parameters are considered: nozzle form coefficient α, gravitational acceleration g, friction loss coefficient λ, local loss coefficient ξ, and orifice plate contraction coefficient x of the upstream air supply branch pipe. u The orifice plate shrinkage coefficient x of the downstream air supply branch pipe b .

[0015] Optionally, the nozzle calculation parameters of the air supply branch pipe calculated based on the aforementioned design experience parameters include:

[0016] Calculate the air supply volume q of the upstream branch pipe. u The downstream branch air supply volume q of the downstream air supply branch pipe b ,satisfy:

[0017] q u = u / (L b + u )*q t q b = b / (L b + u 0*q t ;

[0018] Calculate the nozzle spacing ΔL between two adjacent nozzles of the upstream air supply branch pipe. u The nozzle spacing ΔL between two adjacent nozzles of the downstream air supply branch pipe b ,satisfy:

[0019] ΔL u =2tan(0.5)L u ΔL b =2tan(0.5)Lb ;

[0020] Calculate the number n of nozzles in the upstream air supply branch pipe. u and the number n of nozzles in the upstream air supply branch pipe b , satisfying: n u = / ΔL u n b = / ΔL b ;

[0021] Calculate the nozzle flow rate q of the upstream air supply branch pipe. ju and the nozzle flow rate q of the downstream air supply branch pipe jb , satisfying: q ju = u / n u q jb = b / n b ;

[0022] Calculate the nozzle diameter d of the upstream air supply branch pipe. ju and the initial velocity v of the nozzle jet ju and the nozzle diameter d of the downstream air supply branch pipe jb and the initial velocity v of the nozzle jet jb ,satisfy:

[0023]

[0024]

[0025] Optionally, the branch pipe head loss of the air supply branch pipe is calculated based on the design experience parameters and the nozzle calculation parameters, including:

[0026] Calculate the nozzle friction loss h of the upstream air supply branch pipe. ju and the nozzle friction loss h of the downstream air supply branch pipe jb ,satisfy:

[0027] Calculate the local nozzle loss h' of the upstream air supply branch pipe. ju and the local nozzle loss h' of the downstream air supply branch pipe jb ,satisfy:

[0028] Calculate the local loss h' of the orifice plate in the upstream air supply branch pipe. sou and the local loss h' of the orifice plate of the downstream air supply branch pipe sob ,satisfy:

[0029]

[0030] Optionally, calculating the static pressure head of the air supply branch pipe based on the branch pipe head loss includes:

[0031] Calculate the static pressure head of the upstream branch of the upstream air supply branch and the static pressure head of the downstream branch of the downstream air supply branch, satisfying the following: Where, p at Standard atmospheric pressure.

[0032] Optionally, the branch pipe diameter of the air supply branch pipe is calculated based on the design experience parameters, the branch pipe static pressure head, and the proposed static pressure coefficient k, including:

[0033] Calculate the inlet velocity v of the upstream branch pipe of the upstream air supply branch pipe. u and the downstream branch inlet velocity v of the downstream air supply branch. b ,satisfy:

[0034] Calculate the upstream branch pipe diameter d of the upstream air supply branch pipe. u and the downstream branch pipe diameter d of the downstream air supply branch pipe b ,satisfy:

[0035] Optionally, determining the layout and design parameters of the supply air branch pipes may also include: determining the orifice plate shrinkage coefficient y of the upstream supply air branch pipe. u The shrinkage coefficient y of the large orifice plate of the downstream air supply branch pipe b The throttle valve opening f of the upstream air supply branch pipe u and the throttle valve opening f of the downstream air supply branch pipe b ;

[0036] The branch diameter of the air supply branch is calculated based on the design experience parameters, the branch static pressure head, and the proposed static pressure coefficient k, including: calculating the upstream branch inlet velocity v of the upstream air supply branch. u The downstream branch inlet velocity v of the downstream air supply branch pipe b ;

[0037] The air supply system design method also includes:

[0038] Calculate the local loss h' of the large-orifice plate in the upstream air supply branch pipe. lou and the local loss h' of the large orifice plate of the downstream air supply branch pipe lob ,satisfy:

[0039]

[0040] Calculate the local loss h' of the throttling valve in the upstream air supply branch pipe. vu and the local loss h' of the throttling valve of the upstream air supply branch pipe vb ,satisfy:

[0041] Optionally, the proposed layout and design parameters for the air supply branch pipes may also include: determining the main pipe diameter d of the main air supply pipe and the distance l from the inlet of the main air supply pipe to the connection point of the upstream air supply branch pipe. u The distance l from the inlet of the main air supply pipe to the connection point of the downstream air supply branch pipe b ;

[0042] The calculation parameters for the nozzles of the air supply branch pipe, based on the aforementioned design experience parameters, include: calculating the downstream air supply volume q of the downstream air supply branch pipe. b ;

[0043] The air supply system design method also includes:

[0044] Calculate the friction loss h along the connection point from the inlet of the main air supply pipe to the upstream branch air supply pipe. i-u ,satisfy:

[0045] Calculate the friction loss h along the main air supply pipe from the connection point of the upstream air supply branch pipe to the connection point of the downstream air supply branch pipe. u-b ,satisfy:

[0046] Optionally, calculating the static pressure head of the supply air branch pipe based on the branch pipe head loss includes: calculating the upstream static pressure head p of the upstream supply air branch pipe. u / ρg and the downstream branch static pressure head p of the downstream air supply branch. b / ρg;

[0047] The air supply system design method also includes:

[0048] Calculate the static pressure head p' at the connection between the main air supply pipe and the upstream air supply branch pipe. u / ρg, satisfying:

[0049] Calculate the static pressure head p' at the connection between the main air supply pipe and the downstream air supply branch pipe. b / ρg, satisfying:

[0050] Determine if the equation is satisfied:

[0051] When it is determined that the pressure head equation is satisfied, the throttle valve opening f is adopted. u and the throttle valve opening f b Otherwise, the opening degree f of the throttle valve is... u And / or the throttle valve opening f bMake corrections until the pressure head equation is satisfied.

[0052] Optionally, the air supply system design method further includes:

[0053] Calculate the dynamic head v at the main inlet of the air supply duct. 2 / 2g, of which, v represents the inlet velocity of the main air supply pipe;

[0054] Calculate the static pressure head p at the main inlet of the air supply duct. in / ρg, satisfying:

[0055]

[0056] Select the blower based on the main inlet pressure head information.

[0057] A second aspect of the present invention provides a machine-readable storage medium storing instructions that cause a machine to perform the above-described air supply system design method.

[0058] A third aspect of the present invention provides a processor configured to execute the above-described air supply system design method.

[0059] A fourth aspect of the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the above-described air supply system design method.

[0060] In the design phase, this invention calculates the head loss of the air supply branch pipe while taking into account the influence of pipe resistance; it introduces a static pressure coefficient k to account for the objective situation that static pressure air supply cannot be fully achieved in actual working conditions; and it considers space constraints by determining the size of the branch pipe diameter.

[0061] Therefore, the design results obtained through this invention are more accurate and reliable. Compared with traditional constant cross-section air supply ducts, it is beneficial to improve the flow uniformity of each nozzle. Compared with completely static pressure air supply ducts, due to the introduction of the static pressure coefficient k, it can effectively combine the actual engineering needs and avoid unrestrained expansion of the duct cross-section to reduce dynamic pressure or increase air supply resistance to increase static pressure, thus having better economic efficiency. Compared with traditional variable cross-section air supply ducts, this invention is simple to design and has relatively low requirements for design and process. Compared with CFD simulation, this invention can quickly respond to engineering needs.

[0062] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0063] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0064] Figure 1 This is a schematic diagram of an air supply system according to a specific embodiment of the present invention;

[0065] Figures 2 to 4 These are schematic diagrams illustrating different processes of the air supply system design method in specific embodiments of the present invention. Detailed Implementation

[0066] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0067] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0068] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0069] Existing air supply systems generally include a fan, a main air supply pipe, and branch air supply pipes with multiple nozzles. During operation, the airflow generated by the fan is distributed through the main air supply pipe to one or more branch air supply pipes, and then ejected from the multiple nozzles in the branch air supply pipes, thereby forming a flow field in the enclosed space to achieve purposes such as air purification and pollutant collection. Theoretically, to ensure the uniformity of flow rate at each nozzle, the branch air supply pipes should achieve complete static pressure air supply. However, in practice, due to various forms of airflow losses during flow within the pipes, it is difficult to achieve complete static pressure air supply. Therefore, it is necessary to approach complete static pressure air supply as closely as possible. This condition of approaching complete static pressure air supply can be called quasi-static pressure air supply condition.

[0070] Currently, the design of quasi-static pressure air supply systems in enclosed large spaces mainly relies on two technical means: experience and CFD simulation. However, these two technical means take into account less pipe resistance and have insufficient design capability for the flow distribution of each nozzle in the air supply branch pipe, resulting in a general situation where the flow uniformity of each nozzle is not high.

[0071] In the field of HVAC, there are several design methods that can be used to solve the design problem of uniform air supply in air supply branch pipes. These include four technical means: circular pipe air supply, large cross-section quasi-static pressure air supply, slotted air supply, and variable cross-section air supply.

[0072] For circular tube air supply design, it is essentially a variable cross-section air supply design. The difference is that the cross-section is segmented rather than continuously variable. This design requires segmented calculation of friction resistance and segmented design of pipe diameter. However, the friction resistance coefficient and the flow pattern inside the pipe have a great impact on the accuracy of the design.

[0073] For variable cross-section air supply design, the dynamic pressure difference overcomes the friction resistance by changing the cross-sectional area of ​​the pipe along the pipe, so as to achieve uniform static pressure distribution. However, it places high demands on design accuracy, processing and installation, and is difficult to achieve completely.

[0074] For large-section quasi-static pressure air supply design, quasi-static pressure is achieved by increasing the pipe diameter and reducing the dynamic pressure, but the designed pipe diameter is too large and the space limitation problem is not considered.

[0075] The slotted air supply design relies on the flow distribution of the static pressure chamber and is only suitable for applications with concentrated nozzles.

[0076] In summary, there is still a lack of a rapid design method that can effectively address the design shortcomings of ventilation systems in enclosed large spaces.

[0077] In view of this, refer to Figure 2 A first exemplary embodiment of the present invention provides a method for designing an air supply system, comprising:

[0078] Step S10: Determine the layout and design parameters of the air supply branch pipes;

[0079] Step S20: Calculate the nozzle calculation parameters of the air supply branch pipe based on the design experience parameters;

[0080] Step S30: Calculate the branch pipe head loss of the air supply branch pipe based on the design experience parameters and nozzle calculation parameters;

[0081] Step S40: Calculate the static pressure head of the air supply branch pipe based on the branch pipe pressure head loss;

[0082] Step S50: Calculate the diameter of the air supply branch pipe based on the design experience parameters, the static pressure head of the branch pipe and the proposed static pressure coefficient k, where the static pressure coefficient k is the ratio of the static pressure head to the dynamic pressure head at the inlet of the air supply branch pipe.

[0083] Step S60: Determine whether the diameter of the branch pipe exceeds the preset allowable diameter range;

[0084] Step S70: When it is determined that the branch pipe diameter is within the preset allowable diameter range, the branch pipe diameter is determined to be used; otherwise, the design experience parameters are corrected until the branch pipe diameter is within the preset allowable diameter range.

[0085] As can be seen, in the method of this exemplary embodiment, by executing step S30, the branch head loss of the air supply branch pipe is calculated, taking into account the influence of pipe resistance; by executing step S50, the static pressure coefficient k is introduced, taking into account the objective situation that static pressure air supply cannot be fully realized in actual working conditions; by executing steps S60 to S70, the space limitation problem can be taken into account.

[0086] Therefore, the design results obtained by this method are more accurate and reliable. Compared with traditional constant cross-section air supply ducts, it is beneficial to improve the flow uniformity of each nozzle. Compared with completely static pressure air supply ducts, due to the introduction of the static pressure coefficient k, it can effectively combine the actual needs of the project and avoid unrestrained expansion of the duct cross-section to reduce dynamic pressure or increase static pressure by increasing air supply resistance, which has better economic efficiency. Compared with traditional variable cross-section air supply ducts, this method is simple to design and has relatively low requirements for design and process. Compared with CFD simulation, this method can quickly respond to engineering needs.

[0087] It should be noted that in step S10, the number and location of the air supply branch pipes can be determined based on the actual space. When multiple air supply branch pipes are planned, according to the air supply zoning requirements, all air supply branch pipes can be arranged on the same side of the main air supply pipe (e.g., Figure 1 (As shown); Design experience parameters are parameters that can be formulated based on existing design experience.

[0088] In step S20, the nozzle calculation parameters are nozzle parameters that need to be calculated with the help of design experience parameters. Some nozzle parameters that can be proposed based on existing design experience are nozzle experience parameters, which fall under the category of design experience parameters in this paper.

[0089] In step S70, when it is determined that the diameter of the branch pipe is not within the preset allowable diameter range, the design experience parameters in step S10 need to be corrected, and steps S10 to S60 are executed repeatedly until it is determined that the diameter of the branch pipe is within the preset allowable diameter range. Only then can the correction of the design experience parameters in step S10 and the repeated execution of steps S10 to S60 be stopped.

[0090] After completing steps S10 to S70, the parameters related to the structural characteristics of the air supply branch pipe in the design experience parameters (such as some parameters in the nozzle experience parameters), the nozzle calculation parameters, and the branch pipe diameter can be determined, thus providing a basis for nozzle selection and air supply branch pipe processing when actually arranging the air supply system.

[0091] In one embodiment, reference is made to... Figure 1 The proposed air supply system includes a main air supply pipe 1, an upstream air supply branch pipe 3, and a downstream air supply branch pipe 2. The upstream air supply branch pipe 3 includes multiple nozzles 31 and orifice plates 32, and the downstream air supply branch pipe 2 includes multiple nozzles 21 and orifice plates 22.

[0092] Therefore, step S10 may include:

[0093] Step S101: The main air supply pipe is designed to be connected sequentially to an upstream air supply branch pipe and a downstream air supply branch pipe along the airflow direction within the pipe;

[0094] Step S102: Determine the total air volume q of the main air supply pipe. t The length L of the air distribution area of ​​each of the upstream and downstream air supply branches, and the penetration depth L of the nozzle jet of the upstream air supply branch. u The penetration depth L of the nozzle jet in the downstream air supply branch pipe b The terminal velocity v of the jet stream from the nozzles of the upstream and downstream air supply branches. jm The jet angle θ of the axisymmetric jets from the nozzles of the upstream and downstream air supply branches, and the nozzle friction length l of the upstream air supply branch. ju The nozzle friction length l of the downstream air supply branch pipe jb Nozzle form factor α, gravitational acceleration g, friction loss factor λ, local loss factor ξ, and orifice plate contraction factor x of upstream air supply branch duct. u The orifice plate shrinkage coefficient x of the downstream air supply branch pipe b .

[0095] It should be noted that, referring to Figure 1 In step S101, the arrow in the main air supply pipe 1 indicates the airflow direction inside the main air supply pipe 1, the arrow in the upstream air supply branch pipe 3 indicates the airflow direction inside the upstream air supply branch pipe 3, and the arrow in the downstream air supply branch pipe 2 indicates the airflow direction inside the downstream air supply branch pipe 2. The airflow direction mentioned in step S101 refers to the airflow direction inside the main air supply pipe 1.

[0096] In step S102, the length L of the air distribution area of ​​the upstream air supply branch 3 and the downstream air supply branch 2 are defined to be the same, and the terminal velocity v of the nozzle jet of the upstream air supply branch 3 and the downstream air supply branch 2 is defined to be the same. jmThe same applies to the upstream air supply branch pipe 3 and the downstream air supply branch pipe 2, which are defined to have the same jet angle θ (for example, a value between 26.8° and 30.4°). The same nozzle type coefficient α, gravitational acceleration g, friction loss coefficient λ and local loss coefficient ξ are also defined to be used for the upstream air supply branch pipe 3 and the downstream air supply branch pipe 2.

[0097] Further, step S20 may include:

[0098] Step S201: Calculate the air supply volume q of the upstream branch pipe. u The air supply volume q of the downstream branch pipe and the downstream branch pipe b Satisfying Equations 1 and 2:

[0099] q u =L u / (L b +L u )*q t (Equation 1)

[0100] q b =L b / (L b +L u )*q t (Equation 2);

[0101] Step S202: Calculate the nozzle spacing ΔL between two adjacent nozzles in the upstream air supply branch pipe. u The nozzle spacing ΔL between two adjacent nozzles of the downstream air supply branch pipe b Satisfying equations 3 and 4:

[0102] ΔL u =2tan(0.5θ)L u (Equation 3)

[0103] ΔL b =2tan(0.5θ)L b (Equation 4);

[0104] Step S203: Calculate the number of nozzles n in the upstream air supply branch pipe. u The number of nozzles n in the upstream air supply branch pipe b Satisfying equations 5 and 6:

[0105] n u =L / ΔL u (Equation 5)

[0106] n b =L / ΔL b (Equation 6);

[0107] Step S204: Calculate the nozzle flow rate q of the upstream air supply branch pipe.ju and the nozzle flow rate q of the downstream air supply branch pipe jb Satisfying equations 7 and 8:

[0108] q ju =q u / n u (Equation 7)

[0109] q jb =q b / n b (Equation 8);

[0110] Step S205: Calculate the nozzle diameter d of the upstream air supply branch pipe. ju and the initial velocity v of the nozzle jet ju and the nozzle diameter d of the downstream air supply branch pipe jb and the initial velocity v of the nozzle jet jb Satisfying equations 9 and 10, as well as equations 11 and 12:

[0111]

[0112]

[0113]

[0114]

[0115] The nozzle shape coefficient α is generally taken as 0.07-0.08.

[0116] Further, step S30 may include:

[0117] Step S301: Calculate the nozzle friction loss h of the upstream air supply branch pipe. ju The nozzle friction loss h of the downstream air supply branch pipe jb Satisfying equations 13 and 14:

[0118]

[0119]

[0120] Step S302: Calculate the local nozzle loss h' of the upstream air supply branch pipe. ju Localized nozzle loss h' of downstream air supply branch pipe jb Satisfying equations 15 and 16:

[0121]

[0122]

[0123] Step S303: Calculate the local loss h' of the orifice plate in the upstream air supply branch pipe. sou Localized loss h' of the orifice plate in the downstream air supply branch pipe sob Satisfying equations 17 and 18:

[0124]

[0125]

[0126] It should be noted that the friction loss coefficient λ is related to the Reynolds number and the relative roughness of the pipe wall, and can be determined with reference to relevant experimental curves.

[0127] The nozzle, when spraying outwards, is a flared nozzle transitioning from a small cross-section to an infinitely large cross-section. The local loss coefficient ξ is set to 1, meaning the entire dynamic head of the jet is lost to the environment. If the nozzle is an opening in the wall of a branch duct or a ball valve, friction loss can be ignored; that is, the nozzle friction loss h is negligible. ju and h jb All are 0.

[0128] In addition, refer to Figure 1 The orifice plate is set at the nozzle, and the orifice plate shrinkage coefficient x u The ratio of the orifice plate area of ​​the orifice plate 32 in the upstream air supply branch pipe 3 to the area of ​​the nozzle 31, and the orifice plate contraction coefficient x. b This is the ratio of the orifice plate area of ​​the small orifice plate 22 in the downstream air supply branch duct 2 to the area of ​​the nozzle 21. The thickness of the small orifice plate does not exceed 10 mm, and its friction loss is negligible. The small orifice plate plays a stabilizing role in the static pressure of the air supply branch duct, similar to the function of a static pressure chamber.

[0129] Further, step S40 may include:

[0130] Step S401: Calculate the static pressure head of the upstream branch of the upstream air supply branch and the static pressure head of the downstream branch of the downstream air supply branch, satisfying Equations 19 and 20:

[0131]

[0132]

[0133] Where, p at At standard atmospheric pressure, the static head of the upstream branch pipe is... The static pressure head of the downstream branch pipe is

[0134] Further, step S50 may include:

[0135] Step S501: Calculate the inlet velocity v of the upstream branch pipe of the upstream air supply branch pipe. u and the inlet velocity v of the downstream branch pipe of the downstream air supply branch pipe bSatisfying equations 21 and 22:

[0136]

[0137]

[0138] Step S502: Calculate the diameter d of the upstream branch pipe of the upstream air supply branch pipe. u The diameter d of the downstream branch pipe and the downstream air supply branch pipe b Satisfying equations 23 and 24:

[0139]

[0140]

[0141] It should be noted that the air supply branch duct is responsible for conveying airflow, and achieving completely static pressure air supply is difficult in practice. Therefore, setting the deviation between the flow rates of each nozzle within an acceptable range and maintaining a relatively high static head ratio within the air supply branch duct is more practical. For ease of calculation, this method introduces a static pressure coefficient k, defined as the ratio of the static head to the dynamic head at the inlet of the air supply branch duct. In this embodiment, the static pressure coefficient k... u The static pressure head to dynamic pressure head ratio at the inlet of the upstream air supply branch 3, and the static pressure coefficient k. b This is the ratio of static pressure head to dynamic pressure head at the inlet of the downstream air supply branch 2.

[0142] The larger the static pressure coefficient k, the closer the air supply branch pipe is to a state of complete static pressure air supply, and the smaller the deviation between the flow rates of each nozzle. In the design, the static pressure coefficient k can be determined according to actual needs.

[0143] Further, step S70 may include:

[0144] When it is determined that the branch pipe diameter is not within the preset allowable diameter range, the orifice plate shrinkage coefficient x is adjusted. u and the shrinkage coefficient x of the orifice plate b Make adjustments until the branch pipe diameter is within the preset allowable diameter range.

[0145] Specifically, when it is determined that the diameter of the branch pipe is greater than the upper threshold of the preset allowable diameter range, it indicates a space constraint problem. In this case, it is necessary to reduce the orifice plate shrinkage coefficient x. u and the shrinkage coefficient x of the orifice plate b When the branch pipe diameter is determined to be less than the lower threshold of the preset allowable diameter range, it indicates that the branch pipe diameter is too small. At this time, the orifice plate shrinkage coefficient x u and the shrinkage coefficient x of the orifice plate bIf the diameter is too small, it will place excessively high demands on the static pressure of the pipeline, increasing the cost of selecting the fan while ensuring flow rate. Therefore, when it is determined that the branch pipe diameter is smaller than the lower threshold of the preset allowable diameter range, the orifice plate shrinkage coefficient x needs to be appropriately increased. u and the shrinkage coefficient x of the orifice plate b .

[0146] In one embodiment, reference is made to... Figure 1 The proposed air supply system includes a main air supply pipe 1, an upstream air supply branch pipe 3, and a downstream air supply branch pipe 2. The upstream air supply branch pipe 3 includes a throttle valve 34 and a large orifice plate 33, and the downstream air supply branch pipe 2 includes a throttle valve 24 and a large orifice plate 23.

[0147] Therefore, step S10 may also include:

[0148] Step S103: Determine the orifice plate shrinkage coefficient y of the upstream air supply branch pipe. u The shrinkage coefficient y of the large orifice plate in the downstream air supply branch pipe b The opening degree f of the throttle valve of the upstream air supply branch pipe u The throttle valve opening f of the downstream air supply branch pipe b .

[0149] To verify the throttle valve opening f of the upstream air supply branch pipe 3 u The throttle valve opening f of the downstream air supply branch pipe 2 b Whether the flow distribution between upstream air supply branch 3 and downstream air supply branch 2 can be satisfied depends on the following: Figure 3 The design methods for air supply systems may also include:

[0150] Step S80: Calculate the local loss h' of the large orifice plate in the upstream air supply branch pipe. lou Local loss h' of the large orifice plate in the downstream air supply branch pipe lob Satisfying equations 25 and 26:

[0151]

[0152]

[0153] Step S90: Calculate the local loss h' of the throttling valve in the upstream air supply branch pipe. vu Local loss h' of the throttling valve in the upstream air supply branch pipe vb Satisfying equations 27 and 28:

[0154]

[0155]

[0156] It should be noted that, referring to Figure 1 Throttling valve opening f uSpecifically, it refers to the opening degree of the throttle valve 34 located at the inlet of the upstream air supply branch pipe 3, where the throttle valve opening degree f is... b Specifically, this refers to the opening degree of the throttle valve 24 located at the inlet of the downstream air supply branch pipe 2. The large orifice plate, located at the outlet of the throttle valve, serves to stabilize the flow, i.e., to homogenize the flow field after passing through the throttle valve; the large orifice plate has a contraction coefficient γ. u The ratio of the area of ​​the large-orifice plate 33 in the upstream air supply branch duct 3 to the cross-sectional area of ​​the upstream air supply branch duct 3, and the coefficient of contraction of the large-orifice plate y. b It is the ratio of the area of ​​the large perforated plate 23 in the downstream air supply branch 2 to the cross-sectional area of ​​the downstream air supply branch 2.

[0157] As can be seen, by performing steps S80 and S90, the total head loss at the inlet of the air supply branch pipe can be calculated.

[0158] Furthermore, step S10 may also include:

[0159] Step S104: Determine the main pipe diameter d of the main air supply pipe and the distance l from the inlet of the main air supply pipe to the connection point of the upstream air supply branch pipe. u The distance l between the inlet of the main air supply pipe and the connection point of the downstream air supply branch pipe b ;

[0160] Reference Figure 3 The design methods for air supply systems may also include:

[0161] Step S100: Calculate the friction loss h at the connection point from the inlet of the main air supply pipe to the upstream branch air supply pipe. i-u Satisfying Equation 29:

[0162]

[0163] Step S110: Calculate the friction loss h along the main air supply pipe from the connection point of the upstream air supply branch pipe to the connection point of the downstream air supply branch pipe. u-b Satisfying equation 30:

[0164]

[0165] It can be seen that by performing steps S100 and S110, the total head loss of the main air supply pipe 1 at its inlet to the connection point of the downstream air supply branch pipe 2 can be calculated.

[0166] Furthermore, the air supply system design method may also include:

[0167] Step S120: Calculate the static pressure head p' at the connection between the main air supply pipe and the upstream branch air supply pipe. u / ρg, satisfying equation 31:

[0168]

[0169] Step S130: Calculate the static pressure head p' at the connection between the main air supply pipe and the downstream air supply branch pipe. b / ρg, satisfying equation 32:

[0170]

[0171] Step S140: Determine if equation 33 is satisfied.

[0172]

[0173] Step S150: When it is determined that the head equation is satisfied, determine the throttle valve opening f. u and throttle valve opening f b Otherwise, the throttle valve opening f u and / or throttle valve opening f b Make corrections until the pressure head equation is satisfied.

[0174] As can be seen, the air supply system design method of this exemplary embodiment determines the static pressure head p' at the connection point between the main air supply pipe 1 and the upstream air supply branch pipe 3 and the downstream air supply branch pipe 2. u / ρg、p' b Whether / ρg satisfies equation 33 above can be used to verify the throttle valve opening f. u and throttle valve opening f b Does it meet the flow distribution requirements of the two branch pipes, and can the throttle valve opening f be adjusted based on the verification results? u and / or f b To meet design requirements, crucially, during the verification of the throttle valve opening, the pressure head loss of the throttle valve, the large orifice plate, and the main air supply pipe is taken into account, thereby improving the accuracy of the design and facilitating the realization of quasi-static pressure air supply.

[0175] In one embodiment, reference is made to... Figure 4 The design methods for air supply systems may also include:

[0176] Step S160: Calculate the dynamic head v at the main inlet of the air supply duct. 2 / 2g, of which, v represents the inlet velocity of the main air supply pipe;

[0177] Step S170: Calculate the static pressure head p at the main inlet of the air supply duct. in / ρg, satisfying equation 34:

[0178]

[0179] Step S180: Select the blower based on the main inlet pressure head information.

[0180] As can be seen, by executing steps S160 and S180, the fan model that meets the design requirements can be determined, thus realizing the overall design of the quasi-static pressure air supply system.

[0181] The air supply system design method of this exemplary embodiment can be applied to indoor VOC treatment, odor collection in garbage transfer stations, and other enclosed large-space application scenarios with high requirements for flow field uniformity. It has the following technical features:

[0182] 1. By using a small orifice plate to stabilize the pressure and the branch pipe diameter to be expanded in a limited way, quasi-static pressure air supply can be achieved in the air supply branch pipe, which can achieve uniform air supply over a wide range and with high precision.

[0183] Second, compared with variable cross-section pipes, the system structure obtained according to this design method is simple, has low accuracy requirements for design parameters such as friction resistance, is easy to process and install, and helps to quickly respond to engineering needs.

[0184] Third, the introduction of the static pressure coefficient k can be used to evaluate the uniformity of flow distribution at each nozzle, and has good theoretical guiding significance.

[0185] A second exemplary embodiment of the present invention provides a machine-readable storage medium storing instructions for causing a machine to perform the above-described air supply system design method.

[0186] A third exemplary embodiment of the present invention provides a processor for running a program, which executes the above-described air supply system design method during program execution.

[0187] The processor contains a kernel, which retrieves the corresponding program unit from memory. One or more kernels can be configured, and the dishwasher can be controlled by adjusting the kernel parameters.

[0188] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0189] The fourth exemplary embodiment of the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described air supply system design method.

[0190] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, machine-readable storage media, processors, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-readable program code.

[0191] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0192] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0193] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0194] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0195] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0196] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0197] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0198] The above are merely embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for designing an air supply system, comprising: Determine the layout and design parameters of the air supply branch ducts; The nozzle calculation parameters of the air supply branch pipe are calculated based on the design experience parameters. The branch head loss of the air supply branch pipe is calculated based on the design experience parameters and the nozzle calculation parameters. The static pressure head of the air supply branch pipe is calculated based on the branch pipe pressure head loss. The diameter of the air supply branch pipe is calculated based on the design experience parameters, the static pressure head of the branch pipe, and the proposed static pressure coefficient k, wherein the static pressure coefficient k is the ratio of the static pressure head to the dynamic pressure head at the inlet of the air supply branch pipe. Determine whether the diameter of the branch pipe exceeds the preset allowable diameter range; When it is determined that the diameter of the branch pipe is within the preset allowable diameter range, the branch pipe diameter is adopted; otherwise, the design experience parameters are corrected until the diameter of the branch pipe is within the preset allowable diameter range. The proposed layout and design parameters for the air supply branch ducts include: The main air supply pipe is planned to be connected sequentially to an upstream air supply branch pipe and a downstream air supply branch pipe along the airflow direction inside the pipe. The total air volume q of the proposed air supply main is to be determined. t The length L of the air distribution area of ​​each of the upstream and downstream air supply branches, and the penetration depth L of the nozzle jet of the upstream air supply branch. u The penetration depth L of the nozzle jet in the downstream air supply branch pipe b The terminal velocity v of the jet stream from the nozzles of the upstream and downstream air supply branches. jm The jet angle θ of the axisymmetric jets from the nozzles of the upstream and downstream air supply branches, and the nozzle friction length l of the upstream air supply branch. ju The nozzle friction length l of the downstream air supply branch pipe jb The following parameters are considered: nozzle form coefficient α, gravitational acceleration g, friction loss coefficient λ, local loss coefficient ξ, and orifice plate contraction coefficient x of the upstream air supply branch pipe. u The orifice plate shrinkage coefficient x of the downstream air supply branch pipe b ; The nozzle calculation parameters of the air supply branch pipe, calculated based on the aforementioned design experience parameters, include: Calculate the air supply volume q of the upstream branch pipe. u The downstream branch air supply volume q of the downstream air supply branch pipe b ,satisfy: ， ； Calculate the nozzle spacing ΔL between two adjacent nozzles of the upstream air supply branch pipe. u The nozzle spacing ΔL between two adjacent nozzles of the downstream air supply branch pipe b ,satisfy: ， ； Calculate the number n of nozzles in the upstream air supply branch pipe. u and the number n of nozzles in the upstream air supply branch pipe b ,satisfy: , ; Calculate the nozzle flow rate q of the upstream air supply branch pipe. ju and the nozzle flow rate q of the downstream air supply branch pipe jb ,satisfy: , ; Calculate the nozzle diameter d of the upstream air supply branch pipe. ju and the initial velocity v of the nozzle jet ju and the nozzle diameter d of the downstream air supply branch pipe jb and the initial velocity v of the nozzle jet jb ,satisfy: ， ， ， ； The branch head loss of the air supply branch pipe is calculated based on the design experience parameters and the nozzle calculation parameters, including: Calculate the nozzle friction loss h of the upstream air supply branch pipe. ju and the nozzle friction loss h of the downstream air supply branch pipe jb ,satisfy: , ; Calculate the local nozzle loss h' of the upstream air supply branch pipe. ju and the local loss h' of the nozzle of the downstream air supply branch pipe jb ,satisfy: , ; Calculate the local loss h' of the orifice plate in the upstream air supply branch pipe. sou and the local loss h' of the orifice plate of the downstream air supply branch pipe sob ,satisfy: ， 。 2. The air supply system design method according to claim 1, wherein, The static pressure head of the air supply branch pipe is calculated based on the branch pipe head loss, including: Calculate the static pressure head of the upstream branch of the upstream air supply branch and the static pressure head of the downstream branch of the downstream air supply branch, satisfying the following: , , where p at Standard atmospheric pressure.

3. The air supply system design method according to claim 2, wherein, Based on the aforementioned design experience parameters, the static pressure head of the branch pipe, and the proposed static pressure coefficient k, the diameter of the air supply branch pipe is calculated as follows: Calculate the inlet velocity v of the upstream branch pipe of the upstream air supply branch pipe. u and the downstream branch inlet velocity v of the downstream air supply branch. b ,satisfy: , ; Calculate the upstream branch pipe diameter d of the upstream air supply branch pipe. u and the downstream branch pipe diameter d of the downstream air supply branch pipe b ,satisfy: , .

4. The air supply system design method according to any one of claims 1 to 3, wherein, The proposed layout and design experience parameters for the supply air branch ducts also include: determining the orifice plate shrinkage coefficient y of the upstream supply air branch duct. u The shrinkage coefficient y of the large orifice plate of the downstream air supply branch pipe b The throttle valve opening f of the upstream air supply branch pipe u and the throttle valve opening f of the downstream air supply branch pipe b ; The branch diameter of the air supply branch is calculated based on the design experience parameters, the branch static pressure head, and the proposed static pressure coefficient k, including: calculating the upstream branch inlet velocity v of the upstream air supply branch. u The downstream branch inlet velocity v of the downstream air supply branch pipe b ; The air supply system design method also includes: Calculate the local loss h' of the large-orifice plate in the upstream air supply branch pipe. lou and the local loss h' of the large orifice plate of the downstream air supply branch pipe lob ,satisfy: ， ； Calculate the local loss h' of the throttling valve in the upstream air supply branch pipe. vu and the local loss h' of the throttling valve of the upstream air supply branch pipe vb ,satisfy: , .

5. The air supply system design method according to claim 4, wherein, The proposed layout and design parameters for the air supply branch ducts also include: determining the diameter d of the main air supply pipe and the distance l from the inlet of the main air supply pipe to the connection point of the upstream air supply branch duct. u The distance l from the inlet of the main air supply pipe to the connection point of the downstream air supply branch pipe b ; The calculation parameters for the nozzles of the air supply branch pipe, based on the aforementioned design experience parameters, include: calculating the downstream air supply volume q of the downstream air supply branch pipe. b ; The air supply system design method also includes: Calculate the friction loss h along the connection point from the inlet of the main air supply pipe to the upstream branch air supply pipe. i-u ,satisfy: ; Calculate the friction loss h along the main air supply pipe from the connection point of the upstream air supply branch pipe to the connection point of the downstream air supply branch pipe. u-b ,satisfy: .

6. The air supply system design method according to claim 5, wherein, The calculation of the static head of the supply air branch based on the branch head loss includes: calculating the static head p of the upstream supply air branch. u / ρg and the downstream branch static pressure head p of the downstream air supply branch. b / ρg; The air supply system design method also includes: Calculate the static pressure head p' at the connection between the main air supply pipe and the upstream air supply branch pipe. u / ρg, satisfying: ; Calculate the static pressure head p' at the connection between the main air supply pipe and the downstream air supply branch pipe. b / ρg, satisfying: ; Determine if the equation is satisfied: ; When it is determined that the pressure head equation is satisfied, the throttle valve opening f is adopted. u and the throttle valve opening f b Otherwise, the opening degree f of the throttle valve is... u And / or the throttle valve opening f b Make corrections until the pressure head equation is satisfied.

7. The air supply system design method according to claim 6, wherein, The air supply system design method also includes: Calculate the dynamic head v at the main inlet of the air supply duct. 2 / 2g, of which, v is the inlet velocity of the main air supply pipe; Calculate the static pressure head p at the main inlet of the air supply duct. in / ρg, satisfying: ； Select the blower based on the main inlet pressure head information.

8. A machine-readable storage medium storing instructions that cause a machine to perform the air supply system design method according to any one of claims 1 to 7.

9. A processor configured to execute the air supply system design method according to any one of claims 1 to 7.

10. A computer program product comprising a computer program that, when executed by a processor, implements the air supply system design method according to any one of claims 1 to 7.

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