New air system and control method based on plant and personnel metabolism coupling

Abstract

The present application relates to a kind of new air system and control method based on plant and personnel metabolism coupling, the method comprises: according to indoor plant state and personnel metabolism design the maximum fresh air volume and minimum fresh air volume of new air system;Based on minimum fresh air volume, the minimum light intensity of pre-set system is corrected plant net photosynthetic rate and respiration rate to new air system debugging;Based on pre-set minimum light intensity, the plant net photosynthetic rate and respiration rate of corrected, and personnel quantity fluctuation dynamic adjustment fresh air volume;Combining the real-time fresh air volume of new air system carries out feedback type minimum light intensity adjustment, plant net photosynthetic rate and respiration rate back calculation, and dynamic adjustment of fresh air volume.The new air system and control method of the present application, according to indoor CO2 concentration, photosynthetic active radiation intensity and personnel quantity are comprehensively regulated as needed, and carry out feedback type plant net photosynthetic rate analysis and fresh air volume as needed calculation, real-time control new air system, accurate regulation of new air system is realized.

Description

Technical Field

[0001] This invention relates to the field of fresh air system control technology, and in particular to a fresh air system and control method based on the coupling effect of plant and human metabolism. Background Technology

[0002] Humans inhale O2 and exhale CO2 through respiration. Excessive indoor CO2 concentration can cause headaches, fatigue, and difficulty breathing. To ensure human health, indoor CO2 concentration must be lower than the set maximum CO2 concentration. CO2 acts as nutrients for plants; higher CO2 concentrations help accelerate photosynthesis and promote plant growth. The coupled metabolic processes of plants and humans require an appropriate indoor ventilation system control strategy to meet the needs of both plant growth and human health.

[0003] Given that buildings such as plant pavilions and flower expos have high plant and human density, the metabolism of both people and plants affects air quality, and air quality also affects the health of people and plants. Therefore, a fresh air system control strategy that differs from that of conventional civil buildings is needed to ensure indoor air quality. Summary of the Invention

[0004] Therefore, it is necessary to provide a fresh air system and control method based on the coupling effect of plant and human metabolism to address the above-mentioned technical problems.

[0005] This invention provides a control method for a fresh air system based on the coupling effect of plant and human metabolism, the method comprising:

[0006] The maximum and minimum fresh air volume of the fresh air system are designed based on the condition of indoor plants and the metabolism of people.

[0007] The fresh air system is adjusted based on the minimum fresh air volume to preset the minimum light intensity of the system and correct the net photosynthetic rate and respiration rate of the plants.

[0008] The fresh air volume is dynamically adjusted based on the preset minimum light intensity, the corrected net photosynthetic rate of plants, the respiration rate, and the fluctuations in the number of people.

[0009] The system combines real-time fresh air volume of the fresh air system to perform feedback-based minimum light intensity adjustment, back calculation of plant net photosynthetic rate and respiration rate, and dynamic adjustment of fresh air volume.

[0010] In one embodiment, the design of the maximum and minimum fresh air volume of the fresh air system based on the indoor plant conditions and human metabolism includes:

[0011] Calculate the minimum fresh air volume Q required for plant photosynthesis from the perspective of plant health. min ,for

[0012]

[0013] In the formula, E plant,day E represents the net photosynthetic rate of indoor plants. plant,day =P n ×A leaf / ρ CO2 ;P n The net photosynthetic rate of a plant is represented by a value where the photosynthetic rate is greater than the respiration rate, and a value where the photosynthetic rate is less than the respiration rate is negative. A leaf (m 2 ρ represents the leaf area of ​​plants, which is the product of the leaf area index and the green area; CO2 M1 represents the CO2 gas density; M2 represents the CO2 compensation point concentration for plant photosynthesis; M... out The CO2 concentration of the fresh air;

[0014] Calculate the maximum fresh air volume Q of the system to meet the target indoor CO2 concentration and personnel density from the perspective of human health. max ,for

[0015]

[0016] In the formula, N represents the number of visitors to the exhibition hall, and e people M1 represents the rate at which people exhale CO2; M2 represents the target design CO2 concentration indoors.

[0017] In one embodiment, the adjustment of the fresh air system based on the minimum fresh air volume to preset the minimum light intensity and correct the net photosynthetic rate and respiration rate of the plants includes:

[0018] When the number of people in the room N = 0, and the indoor CO2 concentration is less than the CO2 compensation point concentration M2, the fresh air system operates at the minimum air volume Q. min When the indoor CO2 concentration is greater than the CO2 compensation point concentration M2, the fresh air system is in standby mode.

[0019] When the indoor CO2 fresh air system is running at its minimum airflow rate, the indoor CO2 concentration M is recorded during the period. τ Given the corresponding time τ and photosynthetically active radiation intensity PFD, the net photosynthetic rate E of all indoor plants was calculated. plant ,for:

[0020]

[0021] In the formula, Q τ Let V be the fresh air volume at time τ, V be the room volume, Δτ be the time step, and ΔM be the fresh air volume at time τ. τ This represents the change in indoor CO2 concentration within a time step Δτ.

[0022] When E plant When E is less than 0, the photosynthetic rate of the plant is greater than the respiration rate; when E plant A value greater than 0 indicates that the plant's photosynthetic rate is less than its respiration rate; in E... plant The photosynthetically active radiation intensity PFD corresponding to a value close to 0 is the system's preset minimum light intensity PFD1;

[0023] When the photosynthetically active radiation intensity PFD ≤ PFD1, the average value at each time point is taken as the rate E of CO2 release by all indoor plants at night or under low light conditions. plant,night That is, the respiratory rate; when PFD>PFD1, multiple sets of data within a day are fitted with a quadratic equation to calculate E under different photosynthetically active radiation intensities (PFD) and CO2 concentrations indoors. plant,day ,

[0024]

[0025] In one embodiment, adjusting the fresh air volume based on a preset minimum light intensity, a corrected net photosynthetic rate of plants, and fluctuations in the number of people includes:

[0026] Based on human health and plant net photosynthetic rate, the first fresh air volume Q1 is calculated to meet the target indoor CO2 concentration and occupancy density.

[0027]

[0028] In the formula, E plant M1 represents the rate at which indoor plants absorb or release CO2 through photosynthesis and respiration; absorption is represented by negative values, and release by positive values. M1 is the target design CO2 concentration for the indoor environment. out CO2 concentration of fresh air

[0029] The second fresh air volume Q2 is required to meet the needs of plant photosynthesis.

[0030]

[0031] When the photosynthetically active radiation intensity PFD≤PFD1 and N=0, the fresh air unit is in standby mode;

[0032] When PFD≤PFD1 and N>0, and the indoor CO2 concentration is greater than or equal to the design target concentration M1, the fresh air volume of the air purifier is calculated based on the first fresh air volume Q1; if the calculated air volume is lower than the system minimum fresh air volume Q... min If the calculated air volume exceeds the system's maximum fresh air volume Q, then the system will operate at the minimum fresh air volume. maxIf the calculated air volume exceeds the preset value of the system's maximum design fresh air volume, an alarm message will be sent to the management personnel to remind the indoor personnel that the number of people has exceeded the limit; if the indoor CO2 concentration is lower than the design target concentration within a preset time, the fresh air system will be in standby mode.

[0033] When the photosynthetically active radiation intensity PFD > PFD1 and N = 0, and the indoor CO2 concentration is less than the CO2 compensation point M2, the current E plant,day Substitute the value into the second fresh air volume Q2 for air volume calculation and operation; if the calculated air volume is lower than the system minimum fresh air volume Q... min If the calculated air volume exceeds the system's maximum fresh air volume Q, then the system will operate at the minimum fresh air volume. max If the indoor CO2 concentration is higher than the CO2 compensation point M2 within a preset time, the fresh air system will be in standby mode.

[0034] When the photosynthetically active radiation intensity PFD > PFD1 and N > 0, and the indoor CO2 concentration is greater than or equal to the design target concentration M1, the fresh air volume of the air purifier is calculated based on the first fresh air volume Q1; if the calculated air volume is lower than the system's minimum fresh air volume Q... min If the calculated air volume exceeds the system's maximum fresh air volume Q, then the system will operate at the minimum fresh air volume. max If the calculated air volume exceeds the preset value of the system's maximum design fresh air volume, an alarm message will be sent to the management personnel to remind the indoor personnel that the limit has been exceeded; if the indoor CO2 concentration is lower than the design target concentration within a preset time, the fresh air system will be in standby mode.

[0035] In one embodiment, the step of combining the real-time fresh air volume of the fresh air system with feedback-type minimum light intensity adjustment, back-calculation of plant net photosynthetic rate, and dynamic adjustment of fresh air volume includes:

[0036] Real-time recording of fresh air volume Q at time τ during the actual operation of the fresh air unit. τ Photosynthetically Active Radiation Intensity (PFD) τ CO2 concentration M τ , number of people N τ Dynamic correction of plant net photosynthetic rate E by back-calculation using feedforward method. plant,τ :

[0037]

[0038] E plant,τ The PFD value corresponding to a moment close to 0 is set as system PFD1;

[0039] When PFD > PFD1, according to E at each time point plant,day PFD and CO2 concentrations were fitted to determine the E suitable for indoor use. plant,day=f(PFD, M) relation, based on the calculated E plant,day Correction value, continue to dynamically adjust the fresh air volume; when PFD≤PFD1, based on the room volume V and the CO2 concentration M at each time point. τ E is calculated using the time step Δτ. plant,night ;

[0040] According to the revised PFD1, E plant,day E plant,night Dynamically adjust the fresh air volume.

[0041] The present invention also provides a fresh air system based on the coupling effect of plant and human metabolism, and a control method for the fresh air system based on the above-mentioned coupling effect of plant and human metabolism, wherein the fresh air system includes an indoor sensor cluster, an indoor occupant number monitoring sensor, an analysis and control unit, a fresh air device, a dehumidification device and a spray humidification device;

[0042] The indoor sensor cluster includes a CO2 concentration sensor, a relative humidity sensor, and a photosynthetically active radiation sensor;

[0043] The analysis and control unit can perform feedback-type plant net photosynthetic rate analysis and on-demand control of fresh air volume; connect and analyze indoor sensor clusters and indoor personnel number monitoring sensor data; and connect and control fresh air devices, dehumidification devices and spray humidification devices.

[0044] The aforementioned fresh air system and control method based on the coupling effect of plant and human metabolism comprehensively regulates the system on demand according to indoor CO2 concentration, photosynthetically active radiation intensity and number of people, and performs feedback-type plant net photosynthetic rate analysis and fresh air volume calculation on demand to regulate the fresh air system in real time, thus achieving relatively accurate regulation of the fresh air system. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0046] Figure 1 This is a flowchart of a control method for a fresh air system based on the coupling effect of plant and human metabolism, according to an embodiment of the present invention.

[0047] Figure 2 This is a diagram illustrating the control steps of a fresh air system based on the coupling effect of plant and human metabolism, according to an embodiment of the present invention.

[0048] Figure 3The trend of CO2 concentration changes during the nighttime commissioning phase;

[0049] Figure 4 This is a diagram showing the initial state of the indoor fresh air system.

[0050] Figure 5 This is a diagram showing the dynamic adjustment of fresh air volume in response to changes in photosynthetically active radiation intensity, indoor CO2 concentration, and number of people. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this specification are for illustrative purposes only and do not represent the only possible implementation.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0055] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0056] People inhale O2 and exhale CO2 through respiration. Excessive indoor CO2 concentration can cause headaches, fatigue, and difficulty breathing. To ensure human health, indoor CO2 concentration must be lower than the set maximum CO2 concentration. The design of fresh air systems in conventional buildings is based on the metabolic needs of people. The "Indoor Air Quality Standard" GB / T18883-2002 stipulates that the indoor fresh air volume should be ≥30m³. 3 The daily average indoor CO2 concentration is <1000 ppm (per person / h). CO2 is equivalent to nutrients for plants; a higher CO2 concentration helps accelerate photosynthesis and promotes plant growth. Plants absorb CO2 and release O2 during photosynthesis. It is estimated that 30% herbaceous cover in the exhibition hall, under sufficient light, can reduce the indoor CO2 concentration by 60% within 1.5 hours. Unlike conventional residential buildings, ventilation in greenhouses is relatively less precise. According to the "Technical Specifications for Plant Maintenance and Management in Chongqing Exhibition Greenhouses," taking the flower area as an example, "Throughout the year, when the indoor temperature exceeds 18℃, depending on the weather, the top windows, side windows, and circulating fans should be opened in a timely manner to maintain ventilation and air circulation within the greenhouse." According to "Modern Greenhouse Engineering," after sunrise, plants absorb a large amount of CO2 from the greenhouse air during photosynthesis, causing a sharp drop in CO2 concentration. Although the respiration of microorganisms and the decomposition of organic matter in the indoor soil release CO2, providing a small supplement, this is far from sufficient. To maintain normal photosynthesis, exhibition halls with continuous nighttime lighting require continuous fresh air ventilation to replenish indoor CO2 concentration. Exhibition halls without continuous nighttime lighting need to start fresh air ventilation immediately after sunrise, and the indoor CO2 concentration must be higher than the set minimum CO2 concentration (e.g., 200-300 ppm). In summary, the metabolic coupling between plants and people requires a corresponding indoor fresh air system control strategy to meet the needs of plant growth and human health.

[0057] Many environmental factors influence plant photosynthetic rates, including leaf temperature, CO2 concentration, photosynthetically active radiation (PAR), and soil moisture. The plants in the exhibition hall are all indoors and artificially cultivated. The environmental factors affecting photosynthesis, namely temperature and soil moisture, are relatively constant. The photosynthetic rate is mainly affected by CO2 concentration and PAR intensity. Existing quantitative studies on the relationship between plant photosynthetic rates and environmental responses still have limitations and cannot be used for general engineering calculations. To simplify the design, this study surveyed 146 species of trees, shrubs, vines, and grasses in 10 regions, including Beijing, Shanghai, Wuhan, and Changsha, measuring daily carbon sequestration per unit leaf area and leaf area index. Empirical values ​​for daytime net photosynthetic rate, nighttime dark respiration rate, and leaf area index of trees, shrubs, herbs, and vines were established to simplify design calculations. However, considering the significant differences in metabolic rates among different plant types, classifying them as trees, shrubs, grasses, and vines may not accurately reflect the actual situation. Therefore, this invention proposes a feedback-based fresh air system regulation method, which uses data from the commissioning and operation phases to correct the metabolic intensity of plants, thereby improving the regulation accuracy of the fresh air system.

[0058] Given that buildings such as plant pavilions and flower expos have high plant and human density, the metabolism of both people and plants affects air quality, and air quality also affects the health of people and plants. Therefore, a fresh air system control strategy that differs from that of conventional civil buildings is needed to ensure indoor air quality.

[0059] The purpose of this invention is to propose an indoor air quality control system based on the coupling effect of plant and human metabolism. The system consists of an indoor CO2 concentration sensor, photosynthetically active radiation intensity, indoor occupant number monitoring sensor, analysis and control unit, and a fresh air system. The analysis and control unit is used to analyze the monitoring data of the indoor sensor cluster and the indoor occupant number monitoring sensor, and to perform feedback-type net photosynthetic rate analysis of plants and on-demand calculation of fresh air volume, thereby controlling the fresh air system in real time.

[0060] The following is combined Figures 1-5 This invention describes a fresh air system and control method based on the coupling effect of plant and human metabolism.

[0061] like Figure 1 As shown, in one embodiment, a control method for a fresh air system based on the coupling effect of plant and human metabolism includes the following steps:

[0062] Step S110: Design the maximum and minimum fresh air volume of the fresh air system based on the condition of indoor plants and the metabolism of people;

[0063] Step S120: Adjust the fresh air system to the preset minimum light intensity and correct the net photosynthetic rate and respiration rate of the plants.

[0064] Step S130: Dynamically adjust the fresh air volume based on the preset minimum light intensity, the corrected net photosynthetic rate of plants, the respiration rate, and fluctuations in the number of people.

[0065] Step S140 involves adjusting the minimum light intensity using a feedback mechanism, back-calculating the net photosynthetic rate and respiration rate of the plants, and dynamically adjusting the fresh air volume in conjunction with the real-time fresh air volume of the fresh air system.

[0066] The control method for a fresh air system based on the coupling effect of plant and human metabolism, as described in this invention, is divided into a design phase, a commissioning phase, and a formal operation phase, and specifically includes the following steps:

[0067] Step A. In the design phase, the fresh air volume is designed based on the condition of indoor plants and the metabolism of people, and the maximum design fresh air volume Q of the system is determined. max and minimum design fresh air volume Q min .

[0068] Step A1. Calculate the minimum fresh air volume Q required for plant photosynthesis. min :

[0069]

[0070]

[0071] Step A2. Calculate the maximum fresh air volume Q of the system to meet the target indoor CO2 concentration and personnel density from the perspective of human health. max :

[0072]

[0073] In equations (1-3), E plant，day (m 3 / h) represents the net photosynthetic rate of the plants within the exhibition hall, calculated during the design phase. plant,day The calculation can be performed using formula (2) and Table 1 based on the design of the plants in the exhibition hall; M2 (ppm) is the minimum indoor CO2 concentration required for plants to perform photosynthesis; M out (ppm) represents the CO2 concentration in the fresh air; P n (g / (m 2 ·h)) represents the net photosynthetic rate of the plant; a positive value indicates that the photosynthetic rate is greater than the respiration rate, and a negative value indicates that the photosynthetic rate is less than the respiration rate; A leaf (m 2 ρ represents the leaf area of ​​plants, which is the product of the leaf area index and the green area; CO2 (g / m 3 () represents the density of CO2 gas, typically taken as 1.997 g / m³. 3 N represents the number of people; e people (m3 / (h·person)) represents the rate at which people exhale CO2; M1 represents the target design CO2 concentration indoors.

[0074] Table 1. Empirical values ​​of plant leaf area index and metabolic parameters

[0075]

[0076] Note: The data in the table above will be optimized as research progresses and the statistical sample increases, or the plant classification may be further refined.

[0077] Step B. Debugging Phase: The fresh air system is debugged to set the system's minimum light intensity PFD1 and correct the plant's net photosynthetic rate E. plant,day and respiratory rate E plant,night The debugging phase typically lasts 1 to 2 days;

[0078] Step B1. When the number of people in the room N = 0, and the indoor CO2 concentration is less than the CO2 compensation point concentration M2, the fresh air system operates at the minimum air volume Q. min During operation, when the indoor CO2 concentration exceeds the CO2 compensation point concentration M2, the fresh air system enters standby mode Q=0. The indoor CO2 concentration M during the recording period is recorded. τ Given the corresponding time τ and the photosynthetically active radiation intensity PFD, the net photosynthetic rate E of all plants in the exhibition hall was calculated. plant ,Right now:

[0079]

[0080] Step B2. In E plant The photosynthetically active radiation intensity PFD corresponding to the value close to 0 (transitioning from positive to negative, or from negative to positive) is the system's preset minimum light intensity PFD1.

[0081] Step B3. When the photosynthetically active radiation intensity PFD ≤ PFD1, take the average value at each time point as the rate E of CO2 release by all indoor plants at night or under low light conditions. plant,night ;

[0082] Step B4. When PFD > PFD1, perform a binary quadratic fitting on multiple sets of data within one day to calculate E under different photosynthetically active radiation intensities (PFD) and CO2 concentrations indoors. plant,day ,

[0083]

[0084] Corrected E plant,night More in line with the actual operating status of the exhibition hall;

[0085] Step C. Formal Operation Phase: Based on the preset minimum light intensity and the corrected net photosynthetic rate of the plant, E... plant,day Respiratory rate E plant,night The fresh air volume is dynamically adjusted based on fluctuations in the number of personnel (N).

[0086] Step C1. Calculate the first fresh air volume Q1 to meet the indoor target CO2 concentration and occupancy density based on human health and plant net photosynthetic rate.

[0087]

[0088] Step C2. Calculate the second fresh air volume Q2 required for plant photosynthesis.

[0089]

[0090] Step C3. Dynamically adjust the fresh air volume according to formula (7) or (8). The specific adjustment method is as follows:

[0091] Step C3.1. When PFD ≤ PFD1,

[0092] Step C3.1.1. If no one is in the room, i.e. N=0, the fresh air unit is in standby mode;

[0093] Step C3.1.2. If there are people indoors, i.e., N>0, when the indoor CO2 concentration is greater than or equal to the design target concentration M1, calculate the fresh air volume of the fresh air unit according to the first fresh air volume Q1 in formula (7); if the calculated air volume is lower than the minimum fresh air volume Q of the system... min If the calculated air volume exceeds the system's maximum fresh air volume Q, then the system will operate at the minimum fresh air volume. max If the calculated air volume exceeds a certain value of the system's maximum design fresh air volume, an alarm message will be sent to the management personnel to remind the indoor personnel that the limit has been exceeded; if the indoor CO2 concentration is lower than the design target concentration M1 within a certain period of time, the fresh air system will be in standby mode.

[0094] Step C3.2 When the photosynthetically active radiation intensity PFD > PFD1,

[0095] Step C3.2.1 If there is no one in the room, i.e. N=0, when the indoor CO2 concentration is less than the CO2 compensation point M2, calculate the air volume according to the second fresh air volume in formula (8);

[0096] Step C3.2.2 If there are people indoors, i.e., N>0, and the indoor CO2 concentration is greater than or equal to the design target concentration M1, set at 1000ppm, calculate the fresh air volume of the fresh air unit according to formula (7). If the calculated air volume exceeds the maximum design fresh air volume of the system, then the maximum air volume Q shall be used. maxThe system operates; simultaneously, when the calculated air volume exceeds a certain value of the system's maximum design fresh air volume, such as 20%, an alarm message is sent to the management personnel to remind the indoor personnel that the limit has been exceeded; when the indoor CO2 concentration is lower than the design target concentration M1 within a certain period of time, the fresh air system is in standby mode.

[0097] Step D. Combine the real-time fresh air volume of the fresh air system to perform feedback-based minimum light intensity adjustment, back calculation of plant net photosynthetic rate and respiration rate, and dynamic adjustment of fresh air volume, as detailed below:

[0098] Step D1. Record the fresh air volume Q at time τ during the actual operation of the fresh air unit in real time. τ Photosynthetically Active Radiation Intensity (PFD) τ CO2 concentration M τ , number of people N τ Dynamic correction of plant net photosynthetic rate E by back-calculation using feedforward method. plant,τ ,Right now:

[0099]

[0100] Step D2. Place E plant,τ The PFD value corresponding to a moment close to 0 is set as system PFD1;

[0101] Step D3. When PFD > PFD1, the net photosynthetic rate of the plant is denoted as E. plant,day According to E at each time point plant,day PFD and CO2 concentrations were fitted to determine the E suitable for indoor use. plant,day =f(PFD, M) relation, based on the calculated E plant,day Correction value, continue to dynamically adjust the fresh air volume;

[0102] Step D4. When PFD ≤ PFD1, take the median value at each time point as the rate E of CO2 release by all indoor plants at night or under low light conditions. plant,night ;

[0103] Step D5. According to the revised PFD1, E plant,day E plant,night Continue with step C to dynamically adjust the fresh air volume.

[0104] As described above, this invention proposes a feedback-based fresh air system regulation method based on the coupling effect of plant and human metabolism. It comprehensively regulates the system according to indoor CO2 concentration, photosynthetically active radiation intensity, and number of people, filling the gap in existing research on fresh air system regulation strategies for buildings such as plant exhibition halls and flower expos.

[0105] In a specific embodiment, the exhibition hall has an area of ​​500m². 2The plant is 4.5m tall. The indoor exhibit features flowering shrubs, covering 30% of the plant's area. Statistics show that the net photosynthetic rate of these shrubs during the day is approximately 1g / (m²). 2 The nighttime dark respiration rate is approximately 0.25 g / (m³). 2 The leaf area is approximately 3.9, and the CO2 compensation point is 50 ppm. The exhibition hall can accommodate 150 people at peak times.

[0106] This invention relates to a fresh air system based on the coupling effect of plant and human metabolism. The system includes an indoor sensor cluster, an indoor occupant number monitoring sensor, an analysis and control unit, a fresh air device, a dehumidification device, and a spray humidification device. The indoor sensor cluster includes a CO2 concentration sensor, a relative humidity sensor, and a photosynthetically active radiation sensor. The analysis and control unit can perform feedback-type analysis of plant net photosynthetic rate and on-demand control of fresh air volume. It connects and analyzes data from the indoor sensor cluster and the indoor occupant number monitoring sensor, and connects and controls the fresh air device, dehumidification device, and spray humidification device.

[0107] This invention relates to a fresh air system regulation process based on the coupling of plant and human metabolism (see...). Figure 2 (As shown).

[0108] Step A. Design phase: Calculate the fresh air volume based on the condition of indoor plants and human metabolism.

[0109] Step A1. Calculate the fresh air volume Q required for plant photosynthesis. min :

[0110]

[0111] Step A2. Calculate the maximum fresh air volume Q of the system to meet the target indoor CO2 concentration and personnel density from the perspective of human health. max :

[0112]

[0113] Step B. Commissioning phase: The fresh air system is commissioned according to the minimum design fresh air volume Q2. The commissioning phase usually lasts 1 to 2 days.

[0114] Step B1, indoor occupancy N = 0. When the indoor CO2 concentration is less than the CO2 compensation point concentration M2, the fresh air system operates at the minimum airflow Q. min During operation, the fresh air system enters standby mode when the indoor CO2 concentration exceeds the CO2 compensation point concentration M2. The indoor CO2 concentration M during the recording period is recorded. τ Given the corresponding time τ and the photosynthetically active radiation intensity PFD, the net photosynthetic rate E of all plants in the exhibition hall is calculated. plant,τ ,

[0115]

[0116] The CO2 concentration trend during the commissioning phase of the example is shown in the attached figure. Figure 3 As shown, assuming the initial indoor CO2 concentration is equal to the outdoor CO2 concentration at 400 ppm, and the time step Δτ is 1 minute, the E values ​​calculated at different times in the example are... plant The values ​​are shown in Table 2;

[0117] Table 2 Relationship between plant net photosynthetic rate and photosynthetically active radiation intensity and indoor CO2 concentration.

[0118]

[0119]

[0120] Step B2. In E plant The photosynthetically active radiation intensity (PFD) approaching 0 (transitioning from positive to negative, or from negative to positive) is the system's preset minimum light intensity, PFD1. In this example, PFD = 0 μmol / (m 2 ·s);

[0121] Step B3. When the photosynthetically active radiation intensity PFD ≤ PFD1, take the median value at each time point as the rate E of CO2 release by all indoor plants at night or under low light conditions. plant,night ;

[0122] In this example, the nighttime respiration rate of the plant is E. plant,night =0.08m 3 / h;

[0123] Step B4: When PFD > PFD1, adjust multiple sets of data within one day, and calculate the E under different photosynthetically active radiation intensities (PFD) and CO2 concentrations indoors using a bivariate quadratic polynomial fitting method. plant,day ,

[0124]

[0125] In the examples, the E of the exhibition hall under different photosynthetically active radiation intensities (PFD) and CO2 concentrations was calculated. plant ,Right now:

[0126] E plant = -0.30035 + 0.00194 × M - 2.53308 × 10 -5 ×PFD-3.98261×10 -6 ×M 2 -2.70287×10 -8 ×PFD 2 -6.5886×10 -7×M×PFD(m 3 / h) (R 2 =0.98762)

[0127] This value better reflects the actual condition of the plants in the exhibition hall and can be used to correct the system's operating airflow and guide the fresh air control during the operation period.

[0128] Step C. Formal Operation Phase: Based on the preset minimum light intensity and the corrected net photosynthetic rate of the plant, E... plant,day Respiratory rate E plant,night The fresh air volume is dynamically adjusted based on fluctuations in the number of personnel (N).

[0129] Step C1. Calculate the first fresh air volume Q1 to meet the indoor target CO2 concentration and occupancy density based on human health and plant net photosynthetic rate.

[0130]

[0131] In the formula, M1 is the target design CO2 concentration indoors; M out E represents the CO2 concentration of the fresh air. plant The result obtained from fitting in step B is:

[0132] E plant,night =0.08m 3 / h,

[0133] E plant,day = -0.30035 + 0.00194 × M - 2.53308 × 10 -5 ×PFD-3.98261×10 -6 ×M 2 -

[0134] 2.70287×10 -8 ×PFD 2 -6.5886×10 -7 ×M×PFD(m 3 / h);

[0135] Step C2. To meet the second fresh air volume Q2 required for plant photosynthesis,

[0136]

[0137] Step C3. Dynamically adjust the fresh air volume according to the first fresh air volume Q1 defined in step C1 or the minimum fresh air volume Q2 defined in step C2. The specific adjustment method is as follows:

[0138] Step C3.1. When PFD ≤ PFD1,

[0139] Step C3.1.1. If no one is in the room, i.e. N=0, the fresh air unit is in standby mode;

[0140] Step C3.1.2. If there are people indoors, i.e., N>0, and the indoor CO2 concentration is greater than or equal to the design target concentration M1, calculate the fresh air volume of the air purifier based on the first fresh air volume Q1; if the calculated air volume is lower than the system's minimum fresh air volume Q... min If the calculated air volume exceeds the system's maximum fresh air volume Q, then the system will operate at the minimum fresh air volume. max If the calculated air volume exceeds a certain value of the system's maximum design fresh air volume, an alarm message will be sent to the management personnel to remind the indoor personnel that the limit has been exceeded; if the indoor CO2 concentration is lower than the design target concentration M1 within a certain period of time, the fresh air system will be in standby mode.

[0141] Step C3.2. When the photosynthetically active radiation intensity PFD > PFD1,

[0142] Step C3.2.1. If there is no one in the room, i.e. N=0, when the indoor CO2 concentration is less than the CO2 compensation point M2, the example takes 100ppm, and the air volume is calculated according to the second fresh air volume;

[0143] like Figure 4 As shown, the initial indoor CO2 concentration is equal to the outdoor concentration, which is 400 ppm. With the increase of photosynthetically active radiation (PFD), plant photosynthesis intensifies, and CO2 absorption begins, gradually decreasing the indoor CO2 concentration. When it falls below the CO2 compensation point (<100 ppm), the fresh air system is turned on (10:00-18:00). The required fresh air volume at this time is: After sunset or when the exhibition hall lights are turned off, the plants' respiration rate exceeds their photosynthetic rate. At this time, the fresh air system can be turned off (19:00-05:00 the next day); repeat the same airflow adjustment measures the next day.

[0144] Step C3.2.2 If there are people indoors, i.e., N>0, and the indoor CO2 concentration is greater than or equal to the design target concentration M1, set at 1000ppm, calculate the fresh air volume of the fresh air unit according to formula (7). If the calculated air volume exceeds the maximum design fresh air volume of the system, then the maximum air volume Q shall be used. max The system operates; simultaneously, when the calculated air volume exceeds a certain value of the system's maximum design fresh air volume, such as 20%, an alarm message is sent to the management personnel to remind the indoor personnel that the limit has been exceeded; when the indoor CO2 concentration is lower than the design target concentration M1 within a certain period of time, the fresh air system is in standby mode.

[0145] As attached Figure 5 As shown, as people enter the venue, the indoor CO2 concentration gradually increases. When it reaches the design target concentration (1000 ppm in this example), the fresh air volume is adjusted according to the formula... Calculate and run (10:00-17:00). After closing, the number of people indoors is reduced to zero. At this time, the air volume operation is performed according to the logic of step C3.2.2 (18:00-6:00 the next day). Repeat the same air volume adjustment measures on the second day.

[0146] Step D. Combine the real-time fresh air volume of the fresh air system to perform feedback-based minimum light intensity adjustment, back calculation of plant net photosynthetic rate and respiration rate, and dynamic adjustment of fresh air volume, as detailed below:

[0147] Step D1. Record the fresh air volume Q at time τ during the actual operation of the fresh air unit in real time. τ Photosynthetically Active Radiation Intensity (PFD) τ CO2 concentration M τ , number of people N τ Dynamic correction of plant net photosynthetic rate E by back-calculation using feedforward method. plant,τ ,Right now:

[0148]

[0149] Step D2. Place E plant,τ The PFD value corresponding to a moment close to 0 is set as system PFD1;

[0150] Step D3. When PFD > PFD1, the net photosynthetic rate of the plant is denoted as E. plant,day According to E at each time point plant,day PFD and CO2 concentrations were fitted to determine the E suitable for indoor use. plant,day =f(PFD, M) relation, based on the calculated E plant,day Correction value, continue to dynamically adjust the fresh air volume;

[0151] Step D4. When PFD ≤ PFD1, take the median value at each time point as the rate E of CO2 release by all indoor plants at night or under low light conditions. plant,night ;

[0152] Step D5. According to the revised PFD1, E plant,day E plant,night Continue with step C to dynamically adjust the fresh air volume.

[0153] Under this operating mode, even if the number of plants in the exhibition hall increases or decreases, the critical photosynthetically active radiation intensity (PFD1) and net photosynthetic rate (E) that conform to the overall metabolic characteristics of the indoor plants can be obtained through feedback calculations. plant Even so, the system can still operate reliably.

[0154] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0155] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A control method of a fresh air system based on plant and personnel metabolic coupling, characterized by, The method comprises: Designing the maximum fresh air volume and the minimum fresh air volume of the fresh air system according to the indoor plant state and the personnel metabolism; Debugging the fresh air system based on the minimum fresh air volume to set the system minimum light intensity, correct the plant net photosynthetic rate and the respiration rate; Dynamically adjusting the fresh air volume based on the preset minimum light intensity, the corrected plant net photosynthetic rate, the respiration rate and the personnel number fluctuation; Combining the real-time fresh air volume of the fresh air system to perform the feedback type minimum light intensity adjustment, the plant net photosynthetic rate and respiration rate back calculation and the dynamic adjustment of the fresh air volume; The method comprises: Based on the calculation of the minimum fresh air volume Q required to meet the photosynthesis of plants from the perspective of meeting plant health min , In the formula, E plant,day Pn is the net photosynthetic rate of indoor plants, ; P n Pn is the net photosynthetic rate of plants, which is positive when the photosynthetic rate is greater than the respiration rate, and negative when the photosynthetic rate is less than the respiration rate; A leaf (m 2 ) is the leaf area of the plant, which is the product of the leaf area index and the green area; ρ CO2 is the CO2 gas density; M2 is the CO2 compensation point concentration for photosynthesis of the plant; M out is the CO2 concentration of fresh air; System maximum fresh air quantity Q based on meeting personnel health angle to calculate meeting indoor target CO2 concentration and personnel density max , wherein N is the number of people, e people is the rate of CO2 exhalation by the people; M1 is the target design CO2 concentration in the room. The method comprises: N = 0, when the indoor CO2 concentration is less than the CO2 compensation point concentration M 2, the fresh air system operates at the minimum air volume Q min when the indoor CO2 concentration is greater than the CO2 compensation point concentration M 2, the fresh air system is in standby mode; M: CO2 concentration in the room during the recording period τ E(τ, PFD): net photosynthetic rate of all plants in the room at time τ plant,τ E(τ, PFD) = aPFD + b In the formula, Q τ is the real-time fresh air volume corresponding to the time τ, V is the volume of the house, Δτ is the time step, and ΔM τ is the change in indoor CO2 concentration within the time step Δτ. When E plant less than 0, the photosynthetic rate of the plant is greater than the respiration rate; when E plant greater than 0, the photosynthetic rate of the plant is less than the respiration rate; in E plant close to 0, the corresponding photosynthetically active radiation intensity PFD is the system preset minimum light intensity PFD1; When photosynthetic active radiation intensity PFD≤PFD1, the median of each time is taken as the rate of CO2 release of all plants in the room at night or in weak light E plant,night i.e. the respiration rate; When PFD > PFD1, debugging a plurality of groups of data fitting within a day, calculated to obtain indoor at different photosynthetic active radiation intensity PFD and CO2 concentration E plant,day , 2. The control method of a primary air system based on plant and personnel metabolic coupling according to claim 1, characterized by, The method comprises: The method comprises: wherein M 1 is the target design CO2 concentration indoors; M out is the CO2 concentration of the fresh air; The first fresh air volume Q1 that meets the indoor target CO2 concentration and the personnel density is calculated based on the personnel health and the plant net photosynthetic rate, and is The second fresh air volume Q2 that meets the plant photosynthesis is calculated, and is When PFD≤PFD1, and N>0, when the indoor CO2 concentration is greater than or equal to the design target concentration M 1, the fresh air machine air volume is calculated according to the first fresh air volume Q1; if the calculated air volume is lower than the minimum fresh air volume Q min of the system, the minimum fresh air volume is run; if the calculated air volume exceeds the maximum fresh air volume Q max of the system, the maximum air volume is run; when the calculated air volume exceeds the preset value of the maximum design fresh air volume of the system, an alarm information is sent to the management personnel to prompt the indoor personnel to exceed; when the indoor CO2 concentration is lower than the design target concentration within the preset time, the fresh air system is in standby mode; When photosynthetic active radiation intensity PFD>PFD1, and N=0, when indoor CO2 concentration is less than CO2 compensation point M 2, the current E plant,day value into the second fresh air quantity Q2 to carry out air quantity calculation and operation; if the calculated air quantity is lower than the minimum fresh air quantity Q min of the system, the minimum fresh air quantity is operated; if the calculated air quantity exceeds the maximum fresh air quantity Q max of the system, the maximum air quantity is operated; when indoor CO2 concentration is higher than CO2 compensation point M2 within a preset time, the fresh air system is in standby mode; When the photosynthetically active radiation intensity PFD > PFD1, and N > 0, when the indoor CO2 concentration is greater than or equal to the design target concentration M 1, the fresh air machine air volume is calculated according to the first fresh air volume Q1; if the calculated air volume is lower than the minimum fresh air volume Q min of the system, the minimum fresh air volume is run; if the calculated air volume exceeds the maximum fresh air volume Q max of the system, the maximum air volume is run; when the calculated air volume exceeds the preset value of the maximum design fresh air volume of the system, an alarm information is sent to the management personnel to prompt the indoor personnel to exceed; when the indoor CO2 concentration is lower than the design target concentration within the preset time, the fresh air system is in standby mode.

3. The control method of a primary air system based on plant and personnel metabolic coupling according to claim 2, characterized by, When the photosynthetic active radiation intensity PFD≤PFD1 and N=0, the fresh air machine is in standby mode; Q τ , photosynthetically active radiation intensity PFD τ , CO2 concentration M τ , number of people N τ , dynamic correction of the feedback type plant net photosynthetic rate inversion E plant, τ : The E plant,τ The PFD value corresponding to the time point close to 0 is set as the system PFD1; When PFD>PFD1, according to the time of each moment E plant,day 、 The method comprises: , CO2 concentration fitting suitable for indoor E plant,day = f ( PFD , M ) relationship, according to the calculated E plant,day Correction value, continue to dynamically adjust the fresh air volume; when PFD≤PFD1, according to the room volume V, the CO2 concentration M τ And time step ∆τ calculation E plant,night ; According to the revised PFD1, E plant,day , E plant,night The fresh air volume dynamic adjustment is performed.

4. A fresh air system based on the metabolic coupling of plants and people, characterized in that, PFD The control method is applied to the fresh air system based on the plant and personnel metabolism coupling according to any one of claims 1 to 3, and the fresh air system comprises an indoor sensor cluster, an indoor personnel number monitoring sensor, an analysis and control unit, a fresh air device, a dehumidification device and a spray humidification device; The indoor sensor cluster comprises a CO2 concentration sensor, a relative humidity sensor and a photosynthetic active radiation sensor; The analysis and control unit can perform the feedback type plant net photosynthetic rate analysis and the on-demand control of the fresh air volume, connect and analyze the indoor sensor cluster and the indoor personnel number monitoring sensor data; The analysis and control unit can connect and control the fresh air device, the dehumidification device and the spray humidification device.

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