A method, device and medium for controlling variable air volume of a fume hood

Abstract

The application discloses a fume hood variable air volume control method, device and medium, and relates to the technical field of general cleaning. The method comprises the following steps: collecting the current pollutant concentration generated in the fume hood; determining the air volume control mode corresponding to the fume hood according to the current pollutant concentration; obtaining experimental information of the fume hood, and determining the experimental process in which the fume hood is located according to the experimental information and experimental operation performed in the fume hood; determining the required air volume corresponding to the fume hood according to the current pollutant concentration, and determining the emission speed of the pollutant in the fume hood according to the experimental process and the current pollutant concentration, so as to determine the emission duration corresponding to the required air volume according to the emission speed; based on the air volume control mode, controlling the fan to discharge the fresh air corresponding to the required air volume of the fume hood within the emission duration; after the fresh air emission is completed, re-detecting the pollutant concentration in the fume hood, and adjusting the required air volume of the fume hood based on the pollutant concentration.

Description

Technical Field

[0001] This application relates to the field of general cleaning technology, and specifically to a method, device and medium for controlling the variable air volume of a fume hood. Background Technology

[0002] As a core piece of equipment for laboratory environmental control, the fume hood's core function is to efficiently remove toxic and harmful gases, dust, and other pollutants generated during experiments by dynamically adjusting the exhaust volume, while ensuring operator safety. Traditional methods typically employ manual termination, lacking the ability to perceive actual pollutant concentrations in real time, which may lead to residual pollution accumulation or unnecessary energy consumption. Summary of the Invention

[0003] To address the aforementioned problems, this application proposes a method for controlling the variable air volume of a fume hood, comprising:

[0004] The sensor installed inside the fume hood identifies the opening height of the fume hood's operating port, and when the opening height is within a preset range, it collects the current concentration of pollutants generated inside the fume hood.

[0005] Based on the current pollutant concentration, determine the airflow control mode corresponding to the fume hood;

[0006] Obtain the experimental information of the fume hood, and determine the experimental procedure in which the fume hood is located based on the experimental information and the experimental operations performed inside the fume hood;

[0007] The required air volume corresponding to the fume hood is determined based on the current pollutant concentration, and the emission rate corresponding to the pollutants in the fume hood is determined based on the experimental procedure and the current pollutant concentration, so as to determine the emission duration corresponding to the required air volume based on the emission rate.

[0008] Based on the air volume control mode, the fan is controlled to discharge fresh air corresponding to the required air volume to the fume hood during the emission duration;

[0009] After the fresh air is exhausted, the concentration of pollutants in the fume hood is re-detected, and the required air volume of the fume hood is adjusted based on the pollutant concentration.

[0010] In one implementation of this application, determining the airflow control mode corresponding to the fume hood based on the current pollutant concentration specifically includes:

[0011] When the current pollutant concentration is greater than a preset concentration threshold, the air volume control mode corresponding to the fume hood is determined to be the linkage control mode.

[0012] Otherwise, the airflow control mode corresponding to the fume hood is determined to be the standard control mode.

[0013] In one implementation of this application, after determining the required air volume corresponding to the fume hood based on the current pollutant concentration, the method further includes:

[0014] When the air volume control mode is the linkage control mode, the target ventilation hood corresponding to the branch pipe in the ventilation state is selected from each branch pipe connected to the main ventilation duct, and the wind speed corresponding to the ventilation hood and the target ventilation hood is obtained respectively.

[0015] When the wind speed of the target fume hood is less than the wind speed of the fume hood itself, the cross-flow ratio between the fume hood and the target fume hood is determined based on the ratio between the wind speeds.

[0016] Based on the crossflow ratio and the flow distance between the target fume hood and the fume hood, the target air volume corresponding to the target fume hood is adjusted in a coordinated manner.

[0017] In one implementation of this application, determining the crossflow ratio between the fume hood and the target fume hood based on the ratio between the wind speeds specifically includes:

[0018] The crossflow ratio between the fume hood and the target fume hood is determined using the following formula:

[0019]

[0020] Where C represents the crossflow ratio in the flow direction from the fume hood to the target fume hood, v1 represents the wind speed of the fume hood, and v2 represents the wind speed of the target fume hood.

[0021] In one implementation of this application, the target air volume corresponding to the target fume hood is adjusted in a coordinated manner based on the crossflow ratio and the flow distance between the target fume hood and the target fume hood, specifically including:

[0022] Based on the cross-flow ratio, calculate the flow rate of pollutants from the target fume hood to the fume hood;

[0023] Based on the flow distance, calculate the attenuation factor of the pollutants flowing from the target fume hood to the fume hood, and determine the flow pollution concentration of the pollutants flowing into the fume hood based on the attenuation factor and the flow rate;

[0024] Determine the compensation air volume corresponding to the flow pollution concentration, and adjust the target air volume corresponding to the target fume hood in conjunction with the compensation air volume.

[0025] In one implementation of this application, determining the emission rate of pollutants within the fume hood based on the experimental procedure and the current pollutant concentration specifically includes:

[0026] Based on the experimental procedures described above, determine the gas release rate corresponding to each pollutant;

[0027] The emission adjustment factor corresponding to the fume hood is determined based on the ratio between the gas release rate and the volume of the fume hood;

[0028] Calculate the emission change rate of the current pollutant concentration based on the required air volume, the volume, and the current pollutant concentration;

[0029] The emission rate corresponding to the pollutants in the fume hood is determined based on the sum of the emission adjustment factor and the emission change rate.

[0030] In one implementation of this application, determining the emission duration corresponding to the required air volume based on the emission rate specifically includes:

[0031] Obtain the operating condition information corresponding to the experimental procedure; wherein, the operating condition information reflects the operation type corresponding to the current experimental procedure, and the operation type includes self-reaction type and manual operation type;

[0032] Based on the operation type, a corresponding concentration benchmark value for the pollutant is determined; wherein, the concentration benchmark value corresponding to the human operation type is less than the concentration benchmark value corresponding to the self-reaction type;

[0033] Based on the emission rate, calculate the duration of emission required for the pollutant to decrease from the current pollution concentration to the concentration baseline.

[0034] In one implementation of this application, collecting the current pollutant concentration generated inside the fume hood specifically includes:

[0035] The pollutants collected by each sensor are analyzed to determine the concentration of each pollutant component generated in the fume hood.

[0036] Determine the pollution index factor corresponding to each pollutant component, and determine the current pollutant concentration generated in the fume hood based on the pollution index factor and the concentration of the pollutant component;

[0037] Determining the required air volume for the fume hood based on the current pollutant concentration specifically includes:

[0038] Based on the concentration of the pollutant components, the required air volume for the corresponding pollutant components is calculated, and based on the required air volume for each pollutant component and the pollution index factor, the required air volume for the fume hood is calculated.

[0039] This application provides a control device for variable air volume in a fume hood, including:

[0040] At least one processor; and,

[0041] At least one processor-communication-connected memory; wherein,

[0042] The memory stores instructions that can be executed by at least one processor, which enables the at least one processor to perform a variable air volume control method for a fume hood as described in any of the preceding claims.

[0043] This application provides a non-volatile computer storage medium storing computer-executable instructions, which are configured as follows:

[0044] A method for controlling the variable air volume of a fume hood as described in any of the preceding items.

[0045] The method for controlling the variable air volume of a fume hood proposed in this application can bring the following beneficial effects:

[0046] Based on real-time concentration dynamics, the air volume control mode and required air volume are determined. Combined with the analysis of pollutant emission rate and calculation of emission duration in experimental procedures, the ventilation needs of different experimental scenarios can be accurately matched. This avoids the risk of residual pollution accumulation due to insufficient exhaust volume when the pollution concentration is high, and can automatically reduce the required air volume after the pollutant concentration decreases, avoiding unnecessary energy consumption caused by long-term high air volume operation in traditional manual mode. Attached Figure Description

[0047] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0048] Figure 1 A flowchart illustrating a method for controlling the variable air volume of a fume hood, provided as an embodiment of this application;

[0049] Figure 2 This is a schematic diagram of a control device for variable air volume in a fume hood, provided as an embodiment of this application. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0051] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0052] like Figure 1 As shown in the embodiment of this application, a method for controlling the variable air volume of a fume hood includes:

[0053] S101: Using sensors installed inside the fume hood, the opening height corresponding to the operating port of the fume hood is identified, and when the opening height is within a preset range, the current concentration of pollutants generated inside the fume hood is collected.

[0054] A displacement sensor is installed on the side of the fume hood's operating opening to detect the vertical opening height of the glass window. When the vertical opening height is 0, meaning the operating opening is closed, the fume hood may be in standby or isolation mode. When the operating opening is open, it allows for arm insertion for experimental operations. During the experiment, pollutants generated are quickly extracted due to the stable negative pressure inside the fume hood. When the opening height of the operating opening is within a preset range, it indicates that the fume hood is in an effective operating scenario. At this time, the pollutant concentration collection process is triggered. Electrochemical sensors and ultraviolet absorption sensors installed in the fume hood are used to detect the concentration of pollutants generated inside in real time. Taking the photoionization sensor for detecting volatile organic compounds (VOCs) as an example, the built-in ultraviolet lamp ionizes VOC molecules in the air into positive and negative ions. The ions move towards the electrode under the influence of an electric field, forming a weak current. After amplification and conversion, the pollutant concentration value is obtained.

[0055] It should be noted that multiple different types of pollutants may coexist in a fume hood, each with different levels of hazard and concentration. In order to accurately assess the pollution status in the fume hood, it is necessary to analyze each pollutant component and determine the overall current pollutant concentration.

[0056] Component analysis is performed on pollutants collected by various sensors to determine the concentration of each pollutant component generated within the fume hood, based on the sensor type. Different pollutants vary in nature, toxicity, and volatility, resulting in varying degrees of pollution. Therefore, each pollutant component has a corresponding pollution index factor. This pollution index factor measures the degree of harm to the environment and human health posed by each pollutant component; its specific value can be set based on actual experimental data, and this application does not impose any limitations on its value. The concentration of each pollutant component is multiplied by its corresponding pollution index factor, and all results are summed to obtain the current pollutant concentration within the fume hood. This current concentration is a comprehensive concentration calculated by integrating the concentrations of various types of pollutants and their corresponding impact levels, reflecting the overall pollution level within the fume hood.

[0057] S102: Determine the airflow control mode corresponding to the fume hood based on the current pollutant concentration.

[0058] Depending on the current pollutant concentration, the fume hood controller will trigger the fume hood to open different airflow control modes, and the ventilation control operations performed by the controller will also be different under different airflow control modes.

[0059] Specifically, when the current pollutant concentration exceeds the preset threshold, the pollutant concentration inside the fume hood is in an excessive state. On the one hand, it is necessary to increase the exhaust volume of the current fume hood to safely remove all pollutants. On the other hand, while increasing the exhaust volume, the fan frequency and speed increase, and the air pressure decreases. The branch pipes corresponding to each fume hood in the laboratory are responsible for introducing the polluted gas inside the fume hood into the main ventilation duct. The main ventilation duct is connected to each branch pipe. If there are other fume hoods in operation in the laboratory, due to the pressure difference between the internal ventilation ducts, pollutants generated by other fume hoods may diffuse to the current fume hood. This will undoubtedly increase the exhaust pressure of the current fume hood. Therefore, when there is a large exhaust pressure in the current fume hood, in order to minimize the possibility of other fume hoods increasing the pollutant concentration, the air volume control mode needs to be adjusted to the linkage control mode. In the linkage control mode, when adjusting the air volume of the fume hood, the mutual influence of airflow between them must be considered to avoid cross-contamination or airflow turbulence. At this time, in addition to the fume hood currently being tested, the variable air volume of other fume hoods connected to the same main ventilation duct in the laboratory also needs to be adjusted in a linkage manner. When the current pollutant concentration is greater than the preset concentration threshold, the exhaust pressure of the fume hood fan is relatively stable. The air volume control mode corresponding to the fume hood can be set to the standard control mode. In the standard control mode, there is no need to adjust other connected fume hoods. Only the variable air volume of the fume hood being monitored needs to be controlled.

[0060] In one embodiment, when the fume hood is in linkage control mode, it is necessary to select the target fume hood corresponding to the branch pipe that is in a ventilated state from the branch pipes connected to the main ventilation duct. Whether it is in a ventilated state can be determined by whether the branch pipe valve is open and whether the fan power supply is normal. After identifying which target fume hoods' exhaust air may affect the fume hood, it is necessary to further analyze the intensity of airflow interaction between them, and wind speed is a key factor in determining the direction and degree of pollutant flow. When the wind speed of this fume hood and the target fume hood are different, the wind speed difference will cause the airflow in the main duct to tilt towards the branch pipe with the higher wind speed, forming cross flow. The cross flow ratio is calculated by the wind speed ratio to quantify the airflow distribution relationship between the two fume hoods.

[0061] When the air velocity in the target fume hood is lower than that in the target fume hood, pollutants extracted by the target fume hood may be drawn back into the target fume hood due to the pressure difference, thus increasing the pollutant concentration in the target fume hood. In this case, the ratio of air velocities between the target and target fume hoods is needed to determine the crossflow ratio between them. The crossflow ratio represents the relative intensity of airflow interaction between the two fume hoods; the higher the crossflow ratio, the greater the likelihood of pollutant flow. The crossflow ratio can be calculated using the following formula:

[0062]

[0063] Where C represents the crossflow ratio in the flow direction from the fume hood to the target fume hood, v1 represents the air velocity in the fume hood, and v2 represents the air velocity in the target fume hood. The fixed parameters in the above formula are calculated by simulating the variable air volume of the fume hood under different operating conditions.

[0064] The intensity of airflow interaction between fume hoods is also related to their flow distance in the main duct, which is calculated as the distance between the nodes where branch pipes connect to the main duct. The closer the flow distance, the stronger the airflow interaction, and correspondingly, the greater the possibility of cross-influence of pollutants on the fume hood, and the larger the required airflow adjustment. Therefore, after determining the cross-flow ratio between the fume hood and the target fume hood, it is also necessary to adjust the target airflow required for the target fume hood in conjunction with the flow distance between them.

[0065] In one embodiment, when multiple fume hoods operate in conjunction with a main ventilation duct, differences in airflow velocity among the hoods may cause pollutants to cross-flow between branch ducts. To maintain a safe pollutant concentration threshold for each fume hood, the required airflow needs to be dynamically adjusted based on the pollutant flow relationship. Given the required airflow and pollutant concentration of the target fume hood, the total amount of pollutants generated can be calculated, which is the product of the pollutant concentration and the required airflow. Then, based on the cross-flow ratio, the flow rate of pollutants from the target fume hood into the fume hood is calculated, which is the product of the total pollutant amount and the cross-flow ratio. Since pollutants attenuate with distance as they flow through the duct, simply determining the flow rate is insufficient to determine the actual amount of pollutants reaching the fume hood; further assessment of the flow pollution concentration is required, taking into account the flow distance.

[0066] As pollutants flow through ventilation ducts, they gradually attenuate due to factors such as friction against the duct walls and air diffusion; the longer the distance, the more significant the attenuation. The degree of attenuation can be characterized by an attenuation factor, which is negatively correlated with the flow distance. The attenuation factor is calculated by measuring the flow distance between the target fume hood and the current fume hood, and then calculating the attenuation factor when the pollutants reach the fume hood. The attenuation factor can be obtained using the following formula:

[0067]

[0068] Among them, v i ,v j Let i and j represent fume hoods respectively, α represent the attenuation coefficient, determined by empirical formulas or experimental data, typically taken as 0.15 / m, and L ij Indicates the distance traveled.

[0069] After determining the attenuation factor, the degree of pollutant attenuation is calculated based on the product of the attenuation factor and the flow rate, i.e., the attenuated pollutant flow rate. By calculating the ratio between the pollutant flow rate and the current required airflow of the fume hood, the attenuated pollutant flow rate is converted into the corresponding flow pollution concentration. The flow pollution concentration represents the actual impact of the pollutants in the target fume hood on the current fume hood. To eliminate this impact, it is necessary to calculate the additional airflow required. By adjusting the required airflow of the target fume hood, its extraction capacity is enhanced, thereby reducing the impact on other fume hoods.

[0070] Based on the mobile pollution concentration and the safe concentration threshold, the additional compensation air volume required to exhaust from the target fume hood is calculated. For example, if the mobile pollution concentration causes the current concentration in the fume hood to exceed the standard by 10%, the additional compensation air volume required by the target fume hood needs to be adjusted according to the ratio between the product of the excess concentration and the current fume hood volume and the emission rate of the target fume hood. This compensation air volume is then fed back to the target fume hood's air volume requirement. Since the target fume hood is the source of pollutant outflow, its air volume requirement is increased to reduce pollutant spillage. Through this coordinated adjustment, it is possible to ensure that pollutants in the current fume hood are effectively controlled, reduce the risk of cross-contamination between multiple fume hoods, and achieve coordinated exhaust of the entire fume hood system.

[0071] S103: Obtain experimental information about the fume hood, and determine the experimental procedure in which the fume hood is located based on the experimental information and the experimental operations performed inside the fume hood.

[0072] The core function of a fume hood is to control airflow to remove contaminants and ensure the safety of laboratory personnel. However, different experimental procedures have vastly different performance requirements for fume hoods, and the gas release rates of the contaminants also vary. For example, in reagent preparation procedures where no chemical reaction occurs, the amount of volatile contaminants released is relatively small, and medium-speed exhaust ventilation is sufficient to filter out the volatile gases. In synthesis procedures, however, highly toxic gaseous raw materials are used, and the temperature rises during the chemical reaction, accelerating the gas release rate. In this case, high-speed exhaust ventilation from the fume hood is required to ensure the safety of laboratory personnel. Therefore, it is necessary to match the required experimental procedures based on experimental information and operations so that the operating parameters of the fume hood can dynamically adapt to changes in the experimental procedures.

[0073] Before starting the experiment, researchers fill in experimental information such as the experiment name, reagents used, main equipment, and operation type through the system interface. The controller can directly obtain this experimental information. The experimental operations involved in the experiment can be obtained by analyzing the combination of feature parameters collected by sensors installed inside the fume hood. After extracting the combination of feature parameters, it is matched with the operation feature library corresponding to the current experiment to obtain the experimental operation to be executed.

[0074] S104: Determine the required air volume for the fume hood based on the current pollutant concentration, and determine the emission rate of the pollutants in the fume hood based on the experimental procedure and the current pollutant concentration, so as to determine the emission duration corresponding to the required air volume based on the emission rate.

[0075] The core function of a fume hood is to control the spread of pollutants through ventilation. Therefore, it is necessary to calculate the required air volume for the safe discharge of pollutants based on the current pollutant concentration and industry exhaust standards. The calculation of the required air volume is similar to obtaining the current pollutant concentration in the fume hood; it involves summing the products of the required air volume for each pollutant component concentration and the pollution index factor. This required air volume is set based on the real-time current pollutant concentration. However, during the discharge process, the pollutant release rate varies under different experimental procedures. Consequently, the discharge rate of pollutants will differ depending on the concentration and experimental procedure. The discharge rate directly affects the duration of airflow discharge in each stage of the fume hood operation.

[0076] In one embodiment, when calculating the emission rate, the gas release rate corresponding to each pollutant is determined according to the experimental procedure. The gas release rate is related to the reaction procedure and the temperature change in the current procedure. The specific values ​​can be obtained by referring to the relevant experimental records and taking the average value.

[0077] Once the gas release rates for different pollutants are determined, the emission adjustment factor for the fume hood is determined based on the ratio between the gas release rate and the volume of the fume hood. The emission adjustment factor is a coefficient used to adjust fume hood emissions; it comprehensively considers the relationship between the pollutant gas release rate and the fume hood volume, reflecting the impact of the fume hood's internal space size on pollutant emissions.

[0078] The required air volume reflects the ventilation capacity of the ventilation system, the fume hood volume determines the space for containing pollutants, and the current pollutant concentration represents the initial state. These three factors together determine the degree to which the ventilation system changes the pollutant concentration over a certain period of time, i.e., the emission change rate. By calculating the emission change rate, we can understand the effectiveness of the ventilation system in controlling the pollutant concentration. Therefore, the emission change rate of the current pollutant concentration can be calculated based on the ratio of the product of the required air volume and the current pollutant concentration to the volume.

[0079] The emission adjustment factor considers the generation of pollutants and the influence of the fume hood volume, while the emission change rate reflects the rate at which the ventilation system changes the current pollutant concentration. Combining these two factors allows for a more comprehensive determination of the actual rate at which pollutants are discharged from the fume hood, thereby better controlling the pollutant concentration within the fume hood and ensuring the safety of the experimental environment. The emission rate represents the actual rate of change of the pollutant concentration within the fume hood over time.

[0080] After determining the emission rate of pollutants, it is necessary to determine the duration of emission from the fume hood at this required air volume. During this emission duration, the pollutant concentration needs to be reduced from the current concentration to the baseline concentration value.

[0081] Specifically, the process involves acquiring operational information corresponding to the experimental procedures, reflecting the current operational type. Operational types include self-reaction and human-operated types. Different operational types present different risks to personnel exposure and controllability of pollutants. During human-operated procedures, personnel are at high exposure risk, requiring stricter concentration control. During self-reaction procedures, personnel may temporarily leave, allowing for a slightly more relaxed concentration baseline. It's important to note that the concentration baseline is not a safety threshold, but rather a value indicating that pollutants have been effectively emitted. When setting the concentration baseline, it can be based on the current emission ratio of the pollutant concentration. Generally, the concentration baseline for the first emission stage needs to ensure that pollutants are effectively emitted but not completely emitted. Typically, this is set to 50% for human-operated procedures and 80% for self-reaction procedures.

[0082] Once the concentration baseline value is determined, the duration of continuous emission required for the pollutant concentration to decrease to the baseline value can be calculated based on the emission rate.

[0083] S105: Based on the air volume control mode, the fan controls the fresh air volume required to be discharged from the fume hood within the emission duration.

[0084] After calculating the duration of continuous emission in the current emission phase, the controller will control the fan to discharge the required amount of fresh air to the fume hood within the continuous emission duration based on the air volume control mode. If it is in the linkage control mode, it is also necessary to adjust the required air volume of other connected fume hoods at the same time.

[0085] S106: After completing the fresh air exhaust, re-detect the pollutant concentration in the fume hood, and adjust the required air volume of the fume hood based on the pollutant concentration.

[0086] After the fresh air exhaust is complete, the pollutant concentration inside the fume hood has reached the baseline value, indicating a significant decrease in pollutant concentration. However, continued exhaust dilution is still necessary. The next stage of exhaust circulation requires re-monitoring the pollutant concentration within the fume hood and setting a corresponding airflow rate based on the diluted concentration. Understandably, as the pollutant concentration decreases, the required airflow rate in the next stage will also decrease, and the fan operating frequency will be adjusted accordingly. Similarly, the baseline concentration for the next stage needs to be recalculated based on the current diluted pollutant concentration. This dynamic adjustment of the required airflow rate based on real-time changes in pollutant concentration prevents energy waste from excessively high airflow rates when the pollutant concentration decreases significantly.

[0087] The above are embodiments of the methods proposed in this application. Based on the same idea, some embodiments of this application also provide devices and non-volatile computer storage media corresponding to the above methods.

[0088] Figure 2 This is a structural schematic diagram of a variable air volume control device for a fume hood, provided as an embodiment of this application. Figure 2 As shown, it includes:

[0089] At least one processor; and,

[0090] At least one processor-communication-connected memory; wherein,

[0091] The memory stores instructions that can be executed by at least one processor, which enables the at least one processor to perform a variable air volume control method for a fume hood as described in any of the preceding claims.

[0092] This application provides a non-volatile computer storage medium storing computer-executable instructions, which are configured as follows:

[0093] A method for controlling the variable air volume of a fume hood as described in any of the preceding items.

[0094] The various embodiments in this application are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and medium embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the description of the method embodiments.

[0095] The devices and media provided in this application are one-to-one with the methods. Therefore, the devices and media also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0096] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0098] 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.

[0099] 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.

[0100] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0101] Memory may include non-persistent storage 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.

[0102] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, 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-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0103] 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 a process, method, article, or apparatus. Without further limitation, 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 said element.

[0104] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for controlling the variable air volume of a fume hood, characterized in that, The method includes: The sensor installed inside the fume hood identifies the opening height of the fume hood's operating port, and when the opening height is within a preset range, it collects the current concentration of pollutants generated inside the fume hood. Based on the current pollutant concentration, determine the airflow control mode corresponding to the fume hood; Obtain the experimental information of the fume hood, and determine the experimental procedure in which the fume hood is located based on the experimental information and the experimental operations performed inside the fume hood; The required air volume corresponding to the fume hood is determined based on the current pollutant concentration, and the emission rate corresponding to the pollutants in the fume hood is determined based on the experimental procedure and the current pollutant concentration, so as to determine the emission duration corresponding to the required air volume based on the emission rate. Based on the air volume control mode, the fan is controlled to discharge fresh air corresponding to the required air volume to the fume hood during the emission duration; After the fresh air is exhausted, the pollutant concentration in the fume hood is re-detected, and the required air volume of the fume hood is adjusted based on the pollutant concentration. Based on the current pollutant concentration, the airflow control mode corresponding to the fume hood is determined, specifically including: When the current pollutant concentration is greater than a preset concentration threshold, the air volume control mode corresponding to the fume hood is determined to be the linkage control mode. Otherwise, the airflow control mode corresponding to the fume hood is determined to be the standard control mode; After determining the required air volume for the fume hood based on the current pollutant concentration, the method further includes: When the air volume control mode is the linkage control mode, the target ventilation hood corresponding to the branch pipe in the ventilation state is selected from each branch pipe connected to the main ventilation duct, and the wind speed corresponding to the ventilation hood and the target ventilation hood is obtained respectively. When the wind speed of the target fume hood is less than the wind speed of the fume hood itself, the cross-flow ratio between the fume hood and the target fume hood is determined based on the ratio between the wind speeds. Based on the crossflow ratio and the flow distance between the target fume hood and the fume hood, the target air volume corresponding to the target fume hood is adjusted in a coordinated manner. Based on the ratio between the wind velocities, the crossflow ratio between the fume hood and the target fume hood is determined, specifically including: The crossflow ratio between the fume hood and the target fume hood is determined using the following formula: in, This indicates the proportion of crossflow in the flow direction from the fume hood to the target fume hood. This indicates the airflow speed of the fume hood. Indicates the air velocity of the target fume hood; Based on the crossflow ratio and the flow distance between the target fume hood and the fume hood itself, the target air volume corresponding to the target fume hood is adjusted in a coordinated manner, specifically including: Based on the cross-flow ratio, calculate the flow rate of pollutants from the target fume hood to the fume hood; Based on the flow distance, calculate the attenuation factor of the pollutants flowing from the target fume hood to the fume hood, and determine the flow pollution concentration of the pollutants flowing into the fume hood based on the attenuation factor and the flow rate; Determine the compensation air volume corresponding to the flow pollution concentration, and adjust the target air volume corresponding to the target fume hood in conjunction with the compensation air volume.

2. The method for controlling the variable air volume of a fume hood according to claim 1, characterized in that, Based on the experimental procedures and the current pollutant concentration, the emission rate of the pollutants inside the fume hood is determined, specifically including: Based on the experimental procedures described above, determine the gas release rate corresponding to each pollutant; The emission adjustment factor corresponding to the fume hood is determined based on the ratio between the gas release rate and the volume of the fume hood; Calculate the emission change rate of the current pollutant concentration based on the required air volume, the volume, and the current pollutant concentration; The emission rate corresponding to the pollutants in the fume hood is determined based on the sum of the emission adjustment factor and the emission change rate.

3. The method for controlling the variable air volume of a fume hood according to claim 1, characterized in that, The emission duration corresponding to the required air volume is determined based on the emission rate, specifically including: Obtain the operating condition information corresponding to the experimental procedure; wherein, the operating condition information reflects the operation type corresponding to the current experimental procedure, and the operation type includes self-reaction type and manual operation type; Based on the operation type, a corresponding concentration benchmark value for the pollutant is determined; wherein, the concentration benchmark value corresponding to the human operation type is less than the concentration benchmark value corresponding to the self-reaction type; Based on the emission rate, calculate the duration of emission required for the pollutant to decrease from the current pollution concentration to the concentration baseline.

4. The method for controlling the variable air volume of a fume hood according to claim 1, characterized in that, The current concentration of pollutants generated within the fume hood is collected, specifically including: The pollutants collected by each sensor are analyzed to determine the concentration of each pollutant component generated in the fume hood. Determine the pollution index factor corresponding to each pollutant component, and determine the current pollutant concentration generated in the fume hood based on the pollution index factor and the concentration of the pollutant component; Determining the required air volume for the fume hood based on the current pollutant concentration specifically includes: Based on the concentration of the pollutant components, the required air volume for the corresponding pollutant components is calculated, and based on the required air volume for each pollutant component and the pollution index factor, the required air volume for the fume hood is calculated.

5. A control device for variable air volume in a fume hood, characterized in that, The device includes: At least one processor; And, a memory communicatively connected to the at least one processor; The memory stores instructions that can be executed by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform a fume hood variable air volume control method as described in any one of claims 1-4.

6. A non-volatile computer storage medium storing computer-executable instructions, characterized in that, The computer-executable instructions are set as follows: A method for controlling the variable air volume of a fume hood as described in any one of claims 1-4.

Images