An air flow ventilation simulation test method, system, device and medium

Abstract

The present invention discloses a method, system, device and medium for airflow ventilation simulation test. The method includes setting an initial experimental environment, obtaining a calculated value of the system pressure loss based on the initial experimental environment, and determining the power system requirements; building an experimental air duct based on the initial experimental environment, providing the power system requirements to the experimental air duct, and obtaining a measured value of the system pressure loss; comparing the calculated value of the system pressure loss with the measured value of the system pressure loss, determining a correction value for the parameters of the experimental air duct, and constructing a digital model of the system pressure loss according to the correction value. The digital model of the system pressure loss is used for the airflow ventilation simulation test. By comparing the theoretical calculated value with the actual measured value, the present invention corrects the material parameters, realizes the combination of simulation technology and model test, reduces the cost while improving the accuracy, and further provides a theoretical basis for the power selection of the full-module high-speed airflow ventilation system by engineering designers.

Description

Technical Field

[0001] The present invention relates to the field of heating, ventilation and air conditioning, and particularly to an air flow ventilation simulation test method, system, device and medium. Background Art

[0002] With the development of computer technology and numerical calculation technology, CFD (Computational Fluid Dynamics) has also developed. Briefly speaking, CFD is equivalent to "virtually" conducting experiments in a computer to simulate the actual fluid flow situation. With the development of CFD technology, many general CFD software has emerged, such as ANSYS Fluent, CFX, OpenFOAM, etc. These software have rich physical models and numerical algorithms, can handle various complex fluid flow problems, and provide a friendly user interface and pre- and post-processing functions, which is convenient for engineers and researchers to carry out simulation calculations and result analysis.

[0003] Current traditional laboratories often require a large number of physical devices and materials, with high costs and complex maintenance. At the same time, they cannot meet our requirements for obtaining various information of different flow fields. Therefore, the application of CFD technology is crucial. Nowadays, in the design stage of the heating and ventilation system, the determination of parameters such as the frictional resistance along the way generally only uses the method of mathematical calculation with empirical formulas. However, theoretical calculations sometimes deviate from the actual situation, and it is costly to build an overall experimental model for conventional experiments. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide an air flow ventilation simulation test method, system, device and medium, aiming to solve the problems that in the current design process of the heating and ventilation system, there are deviations in theoretical calculations and it is costly to build an overall experimental model for conventional experiments.

[0005] To achieve the above purpose, the present invention proposes an air flow ventilation simulation test method, and the air flow ventilation simulation test method includes:

[0006] Set an initial experimental environment, and based on the initial experimental environment, obtain the calculated value of the system pressure loss and determine the power system requirements;

[0007] Build an experimental air duct based on the initial experimental environment, provide the power system requirements to the experimental air duct, and obtain the measured value of the system pressure loss;

[0008] Compare the calculated value of the system pressure loss with the measured value of the system pressure loss, determine the correction value of the experimental air duct parameters, and construct a system pressure loss digital model according to the correction value. The system pressure loss digital model is used for air flow ventilation simulation tests.

[0009] In summary, according to a method for simulating an air flow ventilation experiment proposed by the present invention, an initial experimental environment is set. Based on the initial experimental environment, a calculated value of the system pressure loss is obtained, and the power system requirements are determined. According to the obtained power system requirements, an experimental air duct is built based on the initial experimental environment parameters, and ventilation is carried out on the experimental air duct according to the obtained power system requirements. The measured value of the system pressure loss is obtained. Multiple groups of experimental data are repeated, and the measured value and the calculated value under the same environment are compared to obtain a correction value of the experimental air duct parameters. A digital model of the system pressure loss is built according to the correction value of the experimental air duct parameters to improve the simulation degree and reduce errors. By comparing the theoretical calculated value and the actual measured value, the present invention corrects the material parameters, realizes the combination of the simulation technology and the model test, improves the accuracy while reducing the cost, and further provides a theoretical basis for the power selection of the full-module high-speed air flow ventilation system by engineering designers.

[0010] According to one aspect of the above technical solution, the step of setting the initial experimental environment includes:

[0011] Construct a computational fluid dynamics model, and input the initial experimental environment parameters into the computational fluid dynamics model. The initial experimental environment parameters at least include the initial environmental pressure P, the environmental temperature T, the pipe diameter , the pipe length , the fluid flow velocity , the absolute roughness of the pipe surface , and the resistance coefficient .

[0012] According to one aspect of the above technical solution, after the step of constructing the computational fluid dynamics model and inputting the initial experimental environment parameters into the computational fluid dynamics model, it includes:

[0013] Obtain the calculated value of the system pressure loss through the pipe friction loss calculation formula and the pipe local resistance calculation formula. The calculated value of the system pressure loss includes the pipe friction loss and the local resistance ;

[0014] The pipe friction loss The calculation formula is:

[0015]

[0016]

[0017] Where is the friction resistance coefficient, is the fluid density, is the pipe diameter, is the fluid flow velocity, is the pipe length, is the absolute roughness of the pipe surface, is the logarithmic function, is the Reynolds number, and the Reynolds number is calculated by the formula:

[0018]

[0019] wherein, is the kinematic viscosity of the fluid;

[0020] The local resistance is calculated by the formula:

[0021]

[0022] wherein, is the resistance coefficient;

[0023] Based on the frictional resistance of the pipeline and the local resistance , determine the power system requirements.

[0024] According to one aspect of the above technical solution, in the step of building an experimental air duct based on the initial experimental environment, providing the power demand to the experimental air duct, and obtaining the measured value of the system pressure loss;

[0025] Based on the initial experimental environment parameters, build an experimental air duct, provide the power system requirements to the experimental air duct, and measure the frictional resistance of the pipeline and the local resistance under the current initial experimental environment parameters.

[0026] According to one aspect of the above technical solution, the steps of comparing the calculated value and the measured value of the system pressure loss, determining the correction value of the experimental air duct parameters, and constructing a system pressure loss digital model according to the correction value, and the system pressure loss digital model is used for the airflow ventilation simulation test include:

[0027] Repeat the design to exclude the experimental environment parameters of different groups except the resistance coefficient and the absolute roughness of the pipe surface, obtain the calculated values and measured values of the frictional resistance of the pipeline and the local resistance of multiple groups, compare the calculated values and measured values of the frictional resistance of the pipeline and the local resistance of multiple groups to obtain the correction value of the frictional resistance of the pipeline and the local resistance , and inversely deduce the absolute roughness of the pipe surface and the resistance coefficient Correction value;

[0028] Based on the initial environmental pressure P, environmental temperature T, pipe diameter , pipe length , fluid flow rate , and the absolute roughness of the pipe surface correction value and resistance coefficient correction value, a digital model of the system pressure loss is established.

[0029] The present invention also provides an air flow ventilation simulation test system, which is used to implement the above-mentioned air flow ventilation simulation test method. The system includes:

[0030] A theoretical calculation module for setting an initial experimental environment, obtaining a calculated value of the system pressure loss based on the initial experimental environment, and determining the power system requirements;

[0031] An actual measurement module for building an experimental air duct based on the initial experimental environment, providing the power system requirements to the experimental air duct, and obtaining a measured value of the system pressure loss;

[0032] A pressure loss model module for comparing the calculated value of the system pressure loss and the measured value of the system pressure loss, determining the correction value of the experimental air duct parameters, and constructing a digital model of the system pressure loss according to the correction value. The digital model of the system pressure loss is used for the air flow ventilation simulation test.

[0033] The present invention also provides an air flow ventilation simulation test device, which is used to implement the above-mentioned air flow ventilation simulation test method. The air flow ventilation simulation test device includes an experimental air duct, a power system and a damper respectively arranged at both ends of the experimental air duct, a plurality of wind speed and air volume transmitters arranged in the experimental air duct, a plurality of pressure transmitters, and a data collector electrically connected to the wind speed and air volume transmitters and the pressure transmitters;

[0034] The experimental air duct includes a first pipe section, a second pipe section, and a third pipe section connected in sequence. The second pipe section is bent and connected to both the first pipe section and the second pipe section. Wind speed and air volume transmitters and pressure transmitters are arranged on the first pipe section, the second pipe section, and the third pipe section.

[0035] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the air flow ventilation simulation test method as described above.

[0036] Additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0037] Figure 1 This is a flowchart of the air flow ventilation simulation test method in the first embodiment of the present invention;

[0038] Figure 2 This is a schematic structural diagram of the air flow ventilation simulation test system in the second embodiment of the present invention;

[0039] Figure 3 This is a schematic structural diagram of the air flow ventilation simulation test equipment in the fourth embodiment of the present invention. Detailed Embodiments

[0040] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0041] It should be noted that when an element is referred to as being "fixedly provided on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0043] Embodiment 1

[0044] As Figure 1 shown is a flowchart of an air flow ventilation simulation test method in the first embodiment of the present invention. The air flow ventilation simulation test method includes the following steps S01-step S03, where:

[0045] S01. Set the initial experimental environment. Based on the initial experimental environment, obtain the calculated value of the system pressure loss and determine the power system requirements.

[0046] Input the initial experimental environment parameters into the computational fluid dynamics model. The initial experimental environment parameters at least include the initial environmental pressure P, the environmental temperature T, the pipe diameter , the pipe length , fluid flow rate , absolute roughness of the pipe surface and resistance coefficient . Based on the material of the experimental air duct, the absolute roughness of the pipe surface and resistance coefficient of the pipe material to be used are determined through data query.

[0047] Input the initial ambient pressure P, ambient temperature T, pipe diameter , pipe length , fluid flow rate and other parameters into the numerical model, and discretize the numerical model. The methods include but are not limited to the finite difference method, finite volume method, finite element method, etc. And use the absolute roughness of the pipe surface and resistance coefficient of the pipe material to be used obtained through query as boundary conditions, and call the N - S equation solver for CFD (Computational Fluid Dynamics) simulation to obtain the frictional resistance and local resistance of the pipe.

[0048] Input the initial experimental environment parameters, build a computational fluid dynamics model, and use the frictional resistance calculation formula of the pipe and the local resistance calculation formula of the pipe to obtain the calculated value of the system pressure loss. The calculated value of the system pressure loss includes the frictional resistance and local resistance of the pipe.

[0049] The calculation formula of the frictional resistance of the pipe is:

[0050]

[0051]

[0052] Among them, is the friction resistance coefficient, is the fluid density, is the pipe diameter, is the fluid flow rate, is the pipe length, is the absolute roughness of the pipe surface, is the logarithmic function, is the Reynolds number, and the calculation formula of the Reynolds number is:

[0053]

[0054] Among them, is the kinematic viscosity of the fluid;

[0055] The local resistance has the following calculation formula:

[0056]

[0057] where is the resistance coefficient;

[0058] Based on the frictional resistance of the pipeline and the local resistance the power system requirements are determined.

[0059] S02. Based on the initial experimental environment, an experimental air duct is built, and the power system requirements are provided to the experimental air duct to obtain the measured value of the system pressure loss.

[0060] After obtaining the power system requirements, an experimental air duct is built according to the initial experimental environment parameters, and the power system requirements obtained in step S01 are provided to the experimental air duct. By setting measurement points in the experimental air duct, the frictional resistance of the pipeline under the actual environment and the local resistance are measured.

[0061] S03. Compare the calculated value of the system pressure loss with the measured value of the system pressure loss, determine the correction value of the experimental air duct parameters, and build a digital model of the system pressure loss according to the correction value. The digital model of the system pressure loss is used for the airflow ventilation simulation test.

[0062] Compare the measured values and calculated values of the frictional resistance of the pipeline and the local resistance . If the error between the measured value and the calculated value is within the preset error threshold, multi-specification verification is carried out. At least two different pipe diameters are required for each group of materials for experiments to improve the reliability;

[0063] If the error between the measured value and the calculated value exceeds the preset error threshold, correct the obtained measured value and calculated value

[0064] Based on the principle of controlling variables, after excluding the resistance coefficient and the absolute roughness of the pipeline surface, repeat the design of the experimental environment parameters to obtain multiple sets of calculated values and measured values of the frictional resistance of the pipeline and the local resistance . Compare the calculated value with the measured value to obtain the correction values of the frictional resistance and the local resistance of the pipeline, and inversely deduce the absolute roughness of the pipeline surface and the resistance coefficient correction values.

[0065] where, due to the resistance coefficient and the absolute roughness of the pipe surface cannot be measured by metering methods and can only be obtained by measuring the resistance loss and using the calculation formulas for the frictional resistance and local resistance of the pipe to calculate inversely. Therefore, in order to obtain a more accurate resistance coefficient and the absolute roughness of the pipe surface is used for the power selection of the full-modulus high-speed airflow ventilation system by engineering designers. By using the computational fluid dynamics model to theoretically calculate the calculated value of the system pressure loss and comparing it with the measured value of the actual system pressure loss, the corrected frictional resistance of the pipe and local resistance correction values can be obtained. Among them, the correction method can establish the mapping relationship between the measured value and the calculated value through statistical methods (linear regression, polynomial fitting). Specifically, the quadratic relationship between the wind speed and the resistance loss can be fitted by the least squares method. Using the frictional resistance of the pipe and local resistance correction values to inversely calculate the resistance coefficient and the correction value of the absolute roughness of the pipe surface , and taking the correction values of the resistance coefficient and the absolute roughness of the pipe surface as the boundary conditions of the digital model to obtain the digital model of the system pressure loss.

[0066] Using the calibrated parameters, perform performance simulation calculations for any specifications (full modulus) of the air duct of this material. Finally, establish an air duct resistance coefficient model, clarify the resistance characteristics under different air volumes and wind speeds, and use it for the power selection of the full-modulus high-speed airflow ventilation system by engineering designers.

[0067] In summary, according to an airflow ventilation simulation test method proposed by the present invention, an initial experimental environment is set. Based on the initial experimental environment, the calculated value of the system pressure loss is obtained, and the power system requirements are determined. According to the obtained power system requirements, an experimental air duct is built based on the initial experimental environment parameters, and ventilation is carried out on the experimental air duct according to the obtained power system requirements. The measured value of the system pressure loss is measured, multiple groups of experimental data are repeated, and the measured value and the calculated value in the same environment are compared to obtain the correction value of the experimental air duct parameters. And according to the correction value of the experimental air duct parameters, a digital model of the system pressure loss is built to improve the simulation degree and reduce the error. The present invention corrects the material parameters by comparing the theoretical calculated value and the actual measured value, realizes the combination of the simulation technology and the model test, reduces the cost while improving the accuracy, and further provides a theoretical basis for the power selection of the full-modulus high-speed airflow ventilation system by engineering designers.

[0068] Embodiment 2

[0069] On the other hand, the present invention also provides an air flow ventilation simulation test system. Please refer to Figure 2 , which shows a schematic structural diagram of the air flow ventilation simulation test system in the second embodiment of the present invention. The air flow ventilation simulation test system includes:

[0070] A theoretical calculation module 21, configured to set an initial experimental environment, and based on the initial experimental environment, obtain a calculated value of the system pressure loss and determine the power system requirements;

[0071] An actual measurement module 22, configured to build an experimental air duct based on the initial experimental environment, provide the power system requirements to the experimental air duct, and obtain a measured value of the system pressure loss;

[0072] A pressure loss model module 23, configured to compare the calculated value of the system pressure loss and the measured value of the system pressure loss, determine a correction value of the experimental air duct parameters, and based on the correction value, construct a digital model of the system pressure loss, and the digital model of the system pressure loss is used for the air flow ventilation simulation test.

[0073] Input the initial experimental environment parameters into the computational fluid dynamics model. The initial experimental environment parameters at least include the initial environmental pressure P, the environmental temperature T, the pipe diameter , the pipe length , the fluid flow velocity , the absolute roughness of the pipe surface and the resistance coefficient . Based on the material of the experimental air duct, determine the empirical values of the absolute roughness and the resistance coefficient of the pipe material to be used through data query.

[0074] Input the initial environmental pressure P, the environmental temperature T, the pipe diameter , the pipe length , the fluid flow velocity and other parameters into the digital model, and perform discretization processing on the digital model. The methods include but are not limited to the finite difference method, the finite volume method, and the finite element method, etc. And use the empirical values of the absolute roughness and the resistance coefficient of the pipe material to be used queried as boundary conditions, and call the N-S equation solver to perform CFD (computational fluid dynamics) simulation to obtain the frictional resistance and the local resistance of the pipe.

[0075] After inputting the initial experimental environment parameters and building the computational fluid dynamics model, use the frictional resistance calculation formula of the pipe and the local resistance calculation formula of the pipe to obtain the calculated value of the system pressure loss. The calculated value of the system pressure loss includes the frictional resistance of the pipe and local resistance .

[0076] The frictional resistance of the pipeline The calculation formula is as follows:

[0077]

[0078]

[0079] Among them, is the friction resistance coefficient, is the fluid density, is the pipeline diameter, is the fluid flow velocity, is the pipeline length, is the absolute roughness of the pipeline surface, is the logarithmic function, is the Reynolds coefficient, and the Reynolds coefficient The calculation formula is as follows:

[0080]

[0081] Among them, is the kinematic viscosity of the fluid;

[0082] The local resistance The calculation formula is as follows:

[0083]

[0084] Among them, is the resistance coefficient;

[0085] Based on the frictional resistance of the pipeline and the local resistance , determine the power system requirements.

[0086] After obtaining the power system requirements, build an experimental air duct according to the initial experimental environment parameters, provide the power system requirements obtained in step S01 to the experimental air duct, and set measurement points in the experimental air duct to obtain the frictional resistance of the pipeline under the actual environment and local resistance measurement values.

[0087] Compare the measurement values and calculated values of the frictional resistance of the pipeline and local resistance . If the error between the measurement value and the calculated value is within the preset error threshold, perform multi-specification verification. At least two different pipe diameters are required for each set of materials for experiments to improve reliability;

[0088] If the error between the measured value and the calculated value exceeds the preset error threshold, correct the obtained measured value and calculated value.

[0089] Based on the principle of control variables, after excluding the resistance coefficient and the absolute roughness of the pipe surface, repeat the design of the experimental environment parameters to obtain multiple sets of calculated values and measured values of the pipe friction loss. and local resistance Compare the calculated value and the measured value to obtain the correction values of the pipe friction loss and local resistance, and inversely deduce the absolute roughness of the pipe surface through the calculation formulas of the pipe friction loss and local resistance. and resistance coefficient correction values.

[0090] Among them, since the resistance coefficient and the absolute roughness of the pipe surface cannot be measured by metering methods, it can only be obtained by measuring the resistance loss and inversely deducing through the calculation formulas of the pipe friction loss and local resistance. Therefore, in order to obtain a more accurate resistance coefficient and the absolute roughness of the pipe surface for the power selection of the full-module high-speed airflow ventilation system by engineering designers, use the computational fluid dynamics model to theoretically calculate the calculated value of the system pressure loss and compare it with the measured value of the actual system pressure loss to obtain the corrected pipe friction loss and local resistance correction values. Among them, the correction method can establish the mapping relationship between the measured value and the calculated value through statistical methods (linear regression, polynomial fitting). Specifically, the quadratic relationship between the wind speed and the resistance loss can be fitted by the least squares method. Use the corrected values of the pipe friction loss and local resistance to inversely deduce the correction values of the resistance coefficient and the absolute roughness of the pipe surface , and use the correction values of the resistance coefficient and the absolute roughness of the pipe surface as the boundary conditions of the digital model to obtain the digital model of the system pressure loss.

[0091] Use the calibrated parameters to perform performance simulation calculations for any specifications (full-module) of the air duct of this material, and finally establish an air duct resistance coefficient model to clarify the resistance characteristics under different air volumes and wind speeds, and use it for the power selection of the full-module high-speed airflow ventilation system by engineering designers.

[0092] In summary, for an air flow ventilation simulation test system proposed according to the present invention, an initial experimental environment is set. Based on the initial experimental environment, a calculated value of the system pressure loss is obtained, and the power system requirements are determined. According to the obtained power system requirements, an experimental air duct is built based on the initial experimental environment parameters, and ventilation is carried out in the experimental air duct according to the obtained power system requirements. The measured value of the system pressure loss is obtained, multiple groups of experimental data are repeated, and the measured value and the calculated value in the same environment are compared to obtain a correction value of the experimental air duct parameters. A digital model of the system pressure loss is built according to the correction value of the experimental air duct parameters to improve the simulation degree and reduce errors. By comparing the theoretical calculated value and the actual measured value, the present invention corrects the material parameters, realizes the combination of simulation technology and model test, reduces the cost while improving the accuracy, and further provides a theoretical basis for the power selection of the full-module high-speed air flow ventilation system for engineering designers.

[0093] Embodiment III

[0094] On the other hand, the present invention also proposes a computer-readable storage medium, on which one or more computer programs are stored. When the program is executed by a processor, the above-mentioned air flow ventilation simulation test method is realized.

[0095] Those skilled in the art can understand that the logic or steps represented in the flowchart or described in other ways herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable storage medium for use by an instruction execution system, apparatus or device (such as a computer-based system, a system including a processor, or other systems that can fetch instructions from the instruction execution system, apparatus or device and execute the instructions), or used in combination with these instruction execution systems, apparatus or devices. For the purposes of this specification, a "computer-readable storage medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus or device.

[0096] More specific examples (non-exhaustive list) of computer-readable storage media include the following: an electrical connection part with one or more wirings (electronic device), a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable storage medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, then editing, interpreting, or processing in other suitable ways if necessary, and then storing it in the computer memory.

[0097] Example 4

[0098] Figure 3 An air flow ventilation simulation test device provided for Example 4, the air flow ventilation simulation test device includes an experimental air duct, a power system 13 and a damper 12 respectively arranged at both ends of the experimental air duct, a plurality of wind speed and air volume transmitters and a plurality of pressure transmitters arranged in the experimental air duct, and a data collector electrically connected to the wind speed and air volume transmitters and the pressure transmitters.

[0099] In this embodiment, the pipeline includes a first pipe section, a second pipe section, and a third pipe section connected in sequence. The second pipe section is bent and connected to the first pipe section and the second pipe section respectively. Wind speed and air volume transmitters and pressure transmitters are provided on the first pipe section, the second pipe section, and the third pipe section.

[0100] A power system 13 is provided at one end of the first pipe section away from the second pipe section, and a measurement point 14 and a measurement point 2 15 are respectively arranged at the middle and the end of the first pipe section. A first wind speed and air volume transmitter 2 and a first pressure transmitter 3 are provided at the measurement point 14. The measurement point 2 15 is a turning point, and a second pressure transmitter 4 and a third pressure transmitter 5 are provided. A measurement point 3 16 is also provided at the middle of the second pipe section, and a second wind speed and air volume transmitter 6 and a fourth pressure transmitter 7 are provided therewith. Measurement points 4 17 and 5 18 are provided on the third pipe section. The measurement point 4 17 is a bending point, and a fifth pressure transmitter 8 and a sixth pressure transmitter 9 are provided. A third wind speed and air volume transmitter 10 and a seventh pressure transmitter 11 are provided at the measurement point 5 18, and a damper 12 is provided at the end of the third pipe section.

[0101] Further, the power system 13 can be composed of a centrifugal fan, a centrifugal fan box, a frequency converter, a temperature and humidity sensor, a pressure sensor, etc., to provide pipeline air supply power for the experimental air duct, and the power size is adjusted through the frequency converter.

[0102] After selecting the initial experimental environment parameters to build the experimental air duct, determine the initial wind speed and the maximum wind speed, adjust the damper 12, and conduct a start-up test to ensure that by adjusting the frequency of the damper 12, the wind speed provided by the centrifugal fan is within the set wind speed range of the initial wind speed and the maximum wind speed.

[0103] Before conducting the experiment, read the current ambient temperature, humidity, and atmospheric pressure, adjust the frequency of the centrifugal fan, set the initial wind speed in the pipeline, and record the test data of the first wind speed and air volume transmitter 2, the second wind speed and air volume transmitter 6, the third wind speed and air volume transmitter 10, the first pressure transmitter 3, the second pressure transmitter 4, the third pressure transmitter 5, the fourth pressure transmitter 7, the fifth pressure transmitter 8, the sixth pressure transmitter 9, and the seventh pressure transmitter 11 in sequence through the data collector. Repeat the above test, gradually increase the wind speed until the maximum set wind speed is reached. Organize the data through the data collector, export the test record form, obtain the pressure, air volume, and wind speed distribution data within the set wind speed range for different pipe diameters of the current model, and calculate the absolute roughness of the pipe surface. and the correction value of the resistance coefficient , and based on the obtained absolute roughness of the pipe surface and the correction value of the resistance coefficient , build a digital model of the system pressure loss to improve the accuracy of the digital model and provide a theoretical basis for the power selection of the full-modulus high-speed airflow ventilation system by engineering designers.

[0104] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0105] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. An airflow ventilation simulation test method, characterized in that: The airflow ventilation simulation test method comprises: Construct a computational fluid dynamics model and input initial experimental environment parameters into the computational fluid dynamics model. The initial experimental environment parameters include initial environment pressure P, environment temperature T, pipe diameter , Pipeline length , fluid flow rate , Absolute roughness of pipeline surface and drag coefficient Based on the initial experimental environment, the system pressure loss calculation value is obtained by using the pipeline along-the-way resistance calculation formula and the pipeline local resistance calculation formula. The system pressure loss calculation value includes the pipeline along-the-way resistance and local resistance , and determine powertrain requirements; Based on the initial experimental environment, an experimental air duct is built, the power system requirements are provided to the experimental air duct, and a system pressure loss measurement value is obtained, wherein the system pressure loss measurement value includes the pipeline along-the-way resistance Metered value and local resistance The measurement value of Repeat the design to exclude different groups of experimental environmental parameters except for the resistance coefficient and the absolute roughness of the pipeline surface, and obtain multiple groups of pipeline along-the-way resistance and local resistance Compare the calculated and measured values ​​of multiple groups of pipeline resistance along the way and local resistance The calculated and measured values ​​of the pipeline resistance are obtained and local resistance The absolute roughness of the pipeline surface can be obtained by inverse calculation of the pipeline resistance and local resistance. and drag coefficient The correction value is based on the initial ambient pressure P, ambient temperature T, and pipe diameter , Pipeline length , fluid flow rate , absolute roughness of pipeline surface Correction value and drag coefficient A correction value is used to build a digital model of system pressure loss, and the digital model of system pressure loss is used for airflow ventilation simulation test.

2. The airflow ventilation simulation test method according to claim 1 is characterized in that: The step of obtaining the calculated value of the system pressure loss by using the pipeline along-the-line resistance calculation formula and the pipeline local resistance calculation formula comprises: The pipeline resistance The calculation formula is: in, is the friction coefficient, is the fluid density, is the pipe diameter, is the fluid flow rate, is the pipe length, is the absolute roughness of the pipe surface, is a logarithmic function, is the Reynolds coefficient, and the Reynolds coefficient The calculation formula is: in, is the kinematic viscosity of the fluid; The local resistance The calculation formula is: in, is the drag coefficient; Based on the pipeline resistance and the local resistance , determine the power system requirements.

3. An airflow ventilation simulation test system, characterized in that: The airflow ventilation simulation test system is used to implement the airflow ventilation simulation test method according to any one of claims 1 to 2, and the system includes: Theoretical calculation module, used to set the initial experimental environment, obtain the system pressure loss calculation value based on the initial experimental environment, and determine the power system demand; An actual metering module, used to build an experimental air duct based on the initial experimental environment, provide the power system requirements to the experimental air duct, and obtain a system pressure loss metering value; The pressure loss model module is used to compare the calculated value of the system pressure loss and the measured value of the system pressure loss, determine the correction value of the experimental air duct parameters, and construct a system pressure loss digital model based on the correction value. The system pressure loss digital model is used for airflow ventilation simulation test.

4. An airflow ventilation simulation test device, characterized in that: The airflow ventilation simulation test equipment is used to implement the airflow ventilation simulation test method described in any one of claims 1-2, and the airflow ventilation simulation test equipment includes an experimental air duct, a power system and an air damper respectively arranged at both ends of the experimental air duct, a plurality of wind speed and air volume transmitters and a plurality of pressure transmitters arranged in the experimental air duct, and a data collector electrically connected to the wind speed and air volume transmitter and the pressure transmitter; The experimental air duct includes a first pipe section, a second pipe section, and a third pipe section which are connected in sequence. The second pipe section is bent and connected to the first pipe section and the second pipe section. The first pipe section, the second pipe section, and the third pipe section are all provided with wind speed and volume transmitters and pressure transmitters.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the airflow ventilation simulation test method as described in any one of claims 1-2 is implemented.

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