Carbon dioxide concentration measuring device in high humidity environment and monitoring method

Abstract

The application discloses a kind of high-humidity environment carbon dioxide concentration measuring device and monitoring method, including air collector, host computer, controller and refrigerator, air collector includes working pump, collection pipe, monitoring unit and driver, monitoring unit includes at least two temperature sensors, airflow sensor, concentration sensor and humidity sensor, one temperature sensor is installed in each chamber of collection pipe, and one concentration sensor is installed in initial section and end section of collection pipe respectively.The concentration sensor and the refrigerator are integrated in the collection pipe of the air collector in the application, the collected air can be cooled and dehumidified, the air can be cooled to the dew point temperature, and the water vapor in the air can be quickly condensed, thereby improving the detection accuracy of the concentration sensor and reducing the measurement error.The initial section carbon dioxide concentration can be corrected based on the flow rate, temperature and concentration measurement values and other parameters to improve the accuracy.

Description

Technical Field

[0001] This invention relates to the field of CO2 concentration detection in high humidity environments, and more particularly to a device for measuring carbon dioxide concentration in high humidity environments, as well as a method for monitoring carbon dioxide concentration in high humidity environments. Background Technology

[0002] Carbon dioxide is crucial for crop growth in greenhouses; both excessively high and low concentrations can negatively impact photosynthetic rates. Therefore, it's essential to maintain carbon dioxide concentrations within a suitable range during greenhouse cultivation to maximize photosynthetic rates, promote growth, and increase yield. Different plants have varying CO2 requirements (e.g., tomatoes and cucumbers are CO2-loving crops that require higher CO2 concentrations), necessitating monitoring of CO2 levels within the greenhouse.

[0003] Currently, infrared carbon dioxide sensors are commonly used to monitor carbon dioxide concentration in greenhouses, determining the concentration by measuring the reduction in light intensity. However, to promote plant growth, the humidity inside greenhouses is often high, exceeding 95% at night. Water vapor in high-humidity environments can absorb infrared light, interfering with carbon dioxide concentration detection. Furthermore, condensation may form on the surface of optical components in high-humidity environments, leading to scattering or absorption of infrared light and reducing the sensor's signal-to-noise ratio. Therefore, improving the accuracy of CO2 concentration monitoring in high-humidity environments such as greenhouses is a key challenge that needs to be overcome in greenhouse cultivation. Summary of the Invention

[0004] In view of this, the first objective of the present invention is to provide a carbon dioxide concentration measuring device in a high humidity environment, and the second objective of the present invention is to provide a method for monitoring carbon dioxide concentration in a high humidity environment.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The carbon dioxide concentration measuring device in a high humidity environment according to the present invention includes an air collector, a host computer, a controller, and a cooler; the air collector includes a working pump, a collection pipe disposed at the air inlet of the working pump, a monitoring unit disposed in the collection pipe, and a driver for driving the working pump; the cooler is disposed in the collection pipe, and a drain hole is provided at the bottom of the collection pipe.

[0007] Multiple inclined partitions are arranged at intervals inside the collection tube. The multiple partitions are arranged in parallel and divide the collection tube into multiple chambers. The upper or lower part of the partition between two adjacent chambers has a connecting part. The connecting parts of the multiple partitions are staggered vertically, so that the gas flows forward in a deflected manner inside the collection tube.

[0008] The monitoring unit includes at least two temperature sensors, an airflow sensor for monitoring the airflow velocity inside the collection tube, a concentration sensor for monitoring the carbon dioxide concentration, and a humidity sensor for monitoring the ambient humidity. Each chamber of the collection tube is equipped with one of the temperature sensors, and the initial and final sections of the collection tube are each equipped with one of the concentration sensors. The humidity sensor is installed in a high-humidity environment or at the inlet of the collection tube.

[0009] The temperature sensor, concentration sensor, airflow sensor, and humidity sensor are all communicatively connected to the controller. The driver and cooler are communicatively connected to the controller, and the controller is communicatively connected to the host computer.

[0010] The beneficial effects are: This invention integrates the concentration sensor and the cooler into the collection tube of the air collector, which can cool and dehumidify the collected air, lower the air to the dew point temperature, and thus cause the water vapor in the air to condense quickly, thereby improving the detection accuracy of the concentration sensor and reducing measurement errors.

[0011] The air collector of this invention integrates two concentration sensors, located at the initial and final sections of the air collector's collection tube, respectively. The final section concentration sensor has high monitoring accuracy, and the concentration in the final section can be used to correct the measured concentration in the initial section, further improving the accuracy of the initial section concentration.

[0012] Preferably, the separator has a mounting groove, the cooler is a semiconductor cooling chip disposed in the mounting groove, the cold surface of the cooler is covered with a heat-conducting layer, and a heat dissipation cavity is formed on the separator corresponding to the other side of the cooler. The heat dissipation cavity is connected to the output end of the working pump through a connecting branch pipe.

[0013] In actual installation, a cooler can be installed on the partition between the two chambers to cool and dehumidify the air flowing through it, thereby removing moisture from the air and improving the accuracy of the sensor; the dry air drawn out by the working pump enters the heat dissipation chamber through the connecting branch pipe, which can dissipate heat from the cooler in a timely manner.

[0014] In actual manufacturing, the separator can be either a separator plate or a separator block. When a separator block with a relatively large thickness is used, coolers can be installed on both the left and right sides of the separator block.

[0015] The present invention also provides a method for monitoring carbon dioxide concentration in a high humidity environment. The monitoring method uses a carbon dioxide concentration measuring device in a high humidity environment, which includes an air collector, a host computer, a controller, and a cooler. The air collector includes a working pump, a collection pipe disposed at the air inlet of the working pump, a monitoring unit disposed in the collection pipe, and a driver for driving the working pump. The cooler is disposed in the collection pipe, and a drain hole is provided at the bottom of the collection pipe.

[0016] Multiple inclined partitions are arranged at intervals inside the collection tube. The multiple partitions are arranged in parallel and divide the collection tube into multiple chambers. The upper or lower part of the partition between two adjacent chambers has a connecting part. The connecting parts of the multiple partitions are staggered vertically, so that the gas flows forward in a deflected manner inside the collection tube.

[0017] The monitoring unit includes at least two temperature sensors, an airflow sensor for monitoring the airflow velocity inside the collection tube, a concentration sensor for monitoring the carbon dioxide concentration, and a humidity sensor for monitoring the ambient humidity. Each chamber of the collection tube is equipped with one of the temperature sensors, and the initial and final sections of the collection tube are each equipped with one of the concentration sensors. The humidity sensor is installed in a high-humidity environment or at the inlet of the collection tube.

[0018] Among them, the temperature sensor, concentration sensor, airflow sensor and humidity sensor are all communicatively connected to the controller, the driver and the cooler are communicatively connected to the controller, and the controller is communicatively connected to the host computer.

[0019] The monitoring method of the present invention includes the following specific steps:

[0020] S1: Obtain the ambient humidity in the high humidity environment. If the ambient humidity is greater than the preset humidity, generate a dehumidification command to cool and dehumidify the high humidity air entering the air collector, so that the water vapor in the high humidity air condenses into liquid water.

[0021] S2, acquire the airflow velocity, the temperature at the preset temperature measurement point, and the initial carbon dioxide concentration measurement value in the air collector. Use the airflow velocity, the temperature at the measurement point, and the initial carbon dioxide concentration measurement value as the input values ​​of the concentration correction model, and output the first concentration compensation value.

[0022] S3, determine the second concentration compensation value based on ambient humidity, measuring point temperature and airflow velocity;

[0023] S4. The carbon dioxide concentration measurement value of the initial segment is corrected and compensated using the first concentration compensation value and the second concentration compensation value to determine the actual carbon dioxide concentration value of the initial segment.

[0024] The beneficial effects are: This invention integrates the concentration sensor and the cooler into the collection tube of the air collector, which can cool and dehumidify the collected air, lower the air to the dew point temperature, and thus cause the water vapor in the air to condense quickly, thereby improving the detection accuracy of the concentration sensor and reducing measurement errors.

[0025] The air collector of this invention integrates two concentration sensors, located at the initial and final sections of the collector's collection tube, respectively. The air collector has a dehumidification function, which improves the detection accuracy of the final concentration sensor, thereby compensating for and adjusting the actual carbon dioxide concentration in the initial section, thus enhancing accuracy.

[0026] During actual monitoring, although the air humidity in the initial section of the air sampler decreased, it was still relatively high. This application determines the first and second concentration compensation values ​​based on the temperature, flow rate, and concentration of the air sampler, and then corrects and compensates the initial concentration measurement value to obtain the actual carbon dioxide concentration value in the initial section in real time, thereby improving the monitoring accuracy of carbon dioxide concentration and providing a foundation for greenhouse cultivation.

[0027] Preferably, the construction of the concentration correction model in step S2 includes the following:

[0028] S21. Under preset experimental conditions, collect a sample of carbon dioxide concentration measurements in the initial segment within a preset test duration; the preset experimental conditions include preset initial segment carbon dioxide concentration, preset humidity, and preset airflow velocity.

[0029] S22, calculate the initial segment carbon dioxide concentration deviation based on the measured value of the initial segment carbon dioxide concentration and the preset initial segment carbon dioxide concentration;

[0030] S23, adjust any one or more of the preset carbon dioxide concentration, preset humidity and preset airflow speed to obtain several initial segment carbon dioxide concentration measurement values ​​and their corresponding initial segment carbon dioxide concentration deviations. Use the preset experimental conditions and several initial segment carbon dioxide concentration measurement values ​​as input data, input them into the recurrent neural network, and obtain the prediction results.

[0031] S24, compare the predicted result with the initial carbon dioxide concentration deviation corresponding to the initial carbon dioxide concentration measurement value, and calculate the loss value of the loss function of the recurrent neural network;

[0032] S25, the loss value of the root loss function is used to update the parameters of the recurrent neural network to iteratively train the recurrent neural network until it converges, resulting in a trained recurrent neural network, which is then used as the concentration correction model.

[0033] The beneficial effects are: the present invention uses the detected initial carbon dioxide concentration measurement value, airflow velocity, and the temperature of multiple preset temperature measurement points as inputs to the concentration correction model, thereby predicting the error value between the initial carbon dioxide concentration measurement value and the actual initial carbon dioxide concentration measurement value, further determining the actual initial carbon dioxide concentration measurement value, and improving the monitoring accuracy and precision of carbon dioxide.

[0034] Preferably, the second concentration compensation value in this invention includes the following calculation steps:

[0035] S31, using the cross-sectional area of ​​the end of the collection tube as the flow area, the airflow rate per unit time is determined based on the airflow velocity and flow area inside the air collector.

[0036] S32, determine the airflow duration based on the airflow velocity of the air collector, and determine the air collection volume of the air collector based on the airflow rate and airflow duration;

[0037] S33, determine the amount of condensate based on the air collection volume of the air collector and the ambient humidity;

[0038] S34, determine the average temperature inside the air collector based on the temperature of multiple measuring points inside the air collector, and determine the solubility of carbon dioxide based on the average temperature of the air collector.

[0039] S35, Determine the amount of carbon dioxide dissolved based on the solubility of carbon dioxide and the amount of condensate.

[0040] S36. Determine the second concentration compensation value based on the amount of carbon dioxide dissolved and the amount of air collected.

[0041] The beneficial effect is that the second concentration compensation value of the present invention fully considers the effect of condensate on the dissolution of carbon dioxide, and can perform secondary compensation on the carbon dioxide concentration value monitored in the initial stage, thereby further improving the accuracy.

[0042] Preferably, the monitoring method further includes a secondary correction of the first concentration compensation value:

[0043] b1, acquire several final carbon dioxide concentration measurements from the air collector within a preset sampling time, and determine the actual initial carbon dioxide concentration value corresponding to each final carbon dioxide concentration measurement value.

[0044] b2. Calculate the difference between the measured value of carbon dioxide concentration in each final segment and the actual value of carbon dioxide concentration in the corresponding initial segment to obtain several prediction errors. Determine the average prediction error based on these prediction errors.

[0045] b3, the first concentration compensation value is corrected a second time based on the predicted average error.

[0046] The beneficial effects are as follows: This invention determines the time difference between two concentration sensors by collecting the final carbon dioxide concentration measurement value and the flow duration over a period of time, determines the actual value of the initial carbon dioxide concentration corresponding to this period of time based on the time difference, further determines the difference between the final carbon dioxide concentration measurement value at a certain moment and the corresponding actual value of the initial carbon dioxide concentration as the prediction error, and performs a second correction on the first concentration compensation value based on the average value of the prediction error, thereby further improving the accuracy of the actual value of the initial carbon dioxide concentration.

[0047] Compared with the prior art, the advantages of the present invention are as follows:

[0048] This invention integrates a concentration sensor and a cooler into the collection tube of an air collector, which can cool and dehumidify the collected air, bringing it down to the dew point temperature. This causes the water vapor in the air to condense quickly, thereby improving the detection accuracy of the concentration sensor and reducing measurement errors.

[0049] The air collector of this invention integrates two concentration sensors, located at the initial and final sections of the collector's collection tube, respectively. The air collector has a dehumidification function, which improves the detection accuracy of the final concentration sensor, thereby compensating for and adjusting the actual carbon dioxide concentration in the initial section, thus enhancing accuracy.

[0050] During actual monitoring, although the air humidity in the initial section of the air sampler decreased, it was still relatively high. This application determines the first and second concentration compensation values ​​based on the temperature, flow rate, and concentration of the air sampler, and then corrects and compensates the initial concentration measurement value to obtain the actual carbon dioxide concentration value in the initial section in real time, thereby improving the monitoring accuracy of carbon dioxide concentration and providing a foundation for greenhouse cultivation. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the structure of the present invention.

[0052] Figure 2 This is a circuit block diagram of the present invention.

[0053] Figure 3 This is a flowchart of the present invention. Detailed Implementation

[0054] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. These embodiments are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given. However, the scope of protection of the present invention is not limited to the following embodiments.

[0055] It should be noted that, in the description of this invention, relational terms such as “first” and “second” are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0056] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0057] Embodiment 1: This invention proposes a carbon dioxide concentration measuring device in a high humidity environment.

[0058] like Figure 1-3 As shown, this invention proposes a carbon dioxide concentration measuring device in a high humidity environment, including an air collector, a host computer, a controller, and a cooler 1. The air collector includes a working pump 2, a collection pipe 3 located at the air inlet of the working pump 2, a monitoring unit located inside the collection pipe 3, and a driver for driving the working pump 2. The cooler 1 is installed inside the collection pipe 3 and can dehumidify and cool the air drawn in by the air collector (cool the air to the dew point temperature), causing the water vapor in the air to condense into liquid water, reducing the influence of humidity on the concentration sensor 4, thereby improving the detection accuracy of the concentration sensor 4 and reducing measurement errors.

[0059] The collection tube 3 is equipped with multiple inclined partitions at intervals. The partitions are arranged in parallel (with the same inclination direction and angle). The partitions divide the collection tube 3 into multiple chambers. The upper or lower part of the partition between two adjacent chambers has a connecting part. The connecting parts of the multiple partitions are staggered vertically, so that the airflow entering the collection tube 3 flows in an S-shaped path, prolonging the airflow path in the collection tube 3, ensuring that the air drawn into the collection tube 3 is cooled to the dew point temperature, and the humidity of the air is reduced to the minimum.

[0060] A row of drain holes 8 is opened at intervals at the bottom of the collection tube 3, with at least one drain hole 8 corresponding to each chamber, to ensure that the condensate in each chamber is discharged in time and to avoid the accumulation of condensate.

[0061] The monitoring unit includes multiple temperature sensors 5, an airflow sensor for monitoring the airflow speed inside the collection tube 3, a concentration sensor 4 for monitoring carbon dioxide concentration, and a humidity sensor for monitoring ambient humidity (the humidity sensor can be installed inside the greenhouse or at the air inlet of the collection tube). A temperature sensor 5 is installed in each chamber of the collection tube 3. The left end of the collection tube 3 is designated as the initial section, and the right end of the collection tube 3 is designated as the final section. A concentration sensor 4 for detecting carbon dioxide concentration is installed in the initial section and the final section of the collection tube 3, respectively, to monitor the carbon dioxide concentration in the initial section and the final section.

[0062] The temperature sensor 5, concentration sensor 4, airflow sensor, and humidity sensor are all communicatively connected to the controller. The driver and cooler 1 are also communicatively connected to the controller, which in turn is communicatively connected to the host computer. During operation, the sensors transmit the monitored signals to the controller, which then outputs the signals to the host computer for data processing. The host computer controls the driver via the controller to achieve automatic control of the working pump 2. During use, the concentration can be monitored at regular intervals; when not monitoring, the working pump 2 is in a stopped state.

[0063] This invention integrates a concentration sensor 4 and a cooler 1 within the collection tube 3 of an air collector. This cools and dehumidifies the collected air, lowering it to the dew point temperature, causing rapid condensation of water vapor in the air. This improves the detection accuracy of the concentration sensor 4 and reduces measurement errors. The air collector integrates two concentration sensors 4, located at the initial and final sections of the collection tube 3, respectively. The concentration at the final section can be used to compensate for the initial concentration, improving its accuracy and thus enhancing the precise monitoring of carbon dioxide in the greenhouse.

[0064] In actual installation, the controller can be an STM32 series microcontroller or a programmable logic controller (PLC), and the controlled terminal of the driver is connected to the control input terminal of the controller. During monitoring, the controller controls the start and stop of the working pump 2 through the driver; the temperature sensor 5 can also be replaced with a thermocouple or a resistance temperature detector (RTD).

[0065] Combination Figure 1 It is known that the separators include two types: separator plate 6.1 and separator block 6.2. Separator plate 6.1 can be installed at the inlet of the collection pipe 3; a separator block of a certain thickness is installed inside the collection pipe 3, and a cooler 1 is installed on the windward side (i.e., the left side) of the separator block. For thicker separator blocks, coolers 1 can be installed on both the left and right sides to cool the intake air to the dew point temperature as much as possible. In addition, the top or bottom of the separator plate 6.1 or separator block is spaced apart from the collection pipe 3 to form an airflow channel, or through holes are opened in the upper or lower part of the separator plate 6.1 or separator block to ensure the interconnection between multiple chambers and the S-shaped deflection of the airflow.

[0066] In actual installation, the cooler 1 uses a semiconductor cooling chip. A mounting slot is made on the partition block, and the semiconductor cooler 1 is installed in the mounting slot. A heat-conducting layer 9 (preferably a metal sheet with good thermal conductivity) is covered on the cooling surface of the cooler 1 to cool the flowing air. The hot end of the cooler 1 is located within the partition block 6.2. To ensure the heat dissipation performance of the hot end, a heat dissipation cavity 7 is made within the partition block 6.2. The heat dissipation cavity 7 is connected to the output end of the working pump 2 via a connecting branch pipe, and each heat dissipation cavity 7 is connected to the greenhouse environment via an exhaust pipe.

[0067] During monitoring, the working pump 2 starts collecting air, and the cooler 1 cools and condenses the air entering the collection pipe 3. The cooled, dry air then flows from the output of the working pump 2 through connecting branch pipes into each heat dissipation chamber 7, and finally into the greenhouse. This invention utilizes low-temperature, dry air to remove the heat generated by the cooler 1 during operation. Furthermore, the heat generated by the cooler 1 heats the cold air extracted by the working pump 2, increasing the temperature of the discharged air. This reduces the impact of the discharged air on the greenhouse temperature and prevents significant temperature fluctuations.

[0068] The separator 6.2 and separator 6.1 of the present invention are installed at an angle. A cooler 1 is provided on the windward side of the separator 6.2. When the airflow flows, it impacts the heat-conducting layer, so that the airflow and the heat-conducting surface are in full contact, thereby achieving rapid cooling of the intake air. The water condensed after cooling is collected at the bottom of the collection pipe 3 and discharged through the drain hole.

[0069] Implementation Method 2

[0070] This invention proposes a method for monitoring carbon dioxide concentration in high humidity environments. This method is based on the carbon dioxide concentration measuring device in high humidity environments described in Embodiment 1, and the steps are as follows:

[0071] S1, acquire the ambient humidity in the high humidity environment (acquired by a humidity sensor). If the ambient humidity is greater than the preset humidity, generate a dehumidification command. The controller controls the cooler 1 to start cooling, cools and dehumidifies the high humidity air entering the collection tube 3, cools the high humidity air drawn into the collection tube 3 to the dew point temperature, so that the water vapor in the air condenses into liquid water, and reduces the influence of water vapor in the high humidity air on the concentration sensor 4.

[0072] During the cooling process, temperature sensor 5 is used to monitor the temperature of each chamber and airflow channel. When the temperature monitored by temperature sensor 5 is lower than the dew point temperature, the controller controls the cooler 1 in the chamber corresponding to temperature sensor 5 to stop cooling to prevent condensation from freezing and causing blockage of airflow channel or airflow hole.

[0073] S2, acquire the airflow velocity, the temperature at the preset temperature measurement point, and the initial carbon dioxide concentration measurement value in the air collector. Use the airflow velocity, the temperature at the measurement point, and the initial carbon dioxide concentration measurement value as the input values ​​of the concentration correction model, and output the first concentration compensation value.

[0074] In this step, the construction of the concentration correction model includes the following specific contents:

[0075] S21. Under preset experimental conditions, collect a sample of carbon dioxide concentration measurements in the initial segment within a preset test duration; the preset experimental conditions include preset initial segment carbon dioxide concentration, preset humidity, and preset airflow velocity.

[0076] S22, calculate the initial segment carbon dioxide concentration deviation based on the measured value of the initial segment carbon dioxide concentration and the preset initial segment carbon dioxide concentration;

[0077] S23, adjust any one or more of the preset carbon dioxide concentration, preset humidity and preset airflow speed to obtain several initial segment carbon dioxide concentration measurement values ​​and their corresponding initial segment carbon dioxide concentration deviations. Use the preset experimental conditions and several initial segment carbon dioxide concentration measurement values ​​as input data, input them into the recurrent neural network, and obtain the prediction results.

[0078] S24, compare the predicted result with the initial carbon dioxide concentration deviation corresponding to the initial carbon dioxide concentration measurement value, and calculate the loss value of the loss function of the recurrent neural network;

[0079] S25, the loss value of the root loss function is used to update the parameters of the recurrent neural network to iteratively train the recurrent neural network until it converges, resulting in a trained recurrent neural network, which is then used as the concentration correction model.

[0080] This invention uses the initial carbon dioxide concentration measurement value, airflow velocity, and the temperature of multiple preset temperature measurement points as input values ​​for the concentration correction model, thereby predicting the error value between the initial carbon dioxide concentration measurement value and the actual concentration value. The sum of the initial carbon dioxide concentration measurement value and the error value is the actual measurement value of the initial carbon dioxide concentration, thus improving the accuracy of the initial carbon dioxide concentration.

[0081] S3, determine the second concentration compensation value based on ambient humidity, measuring point temperature and airflow velocity;

[0082] S4. The initial carbon dioxide concentration measurement value is corrected and compensated using the first concentration compensation value and the second concentration compensation value to determine the actual carbon dioxide concentration value of the initial segment. The sum of the first concentration compensation value and the initial carbon dioxide concentration measurement value is the actual carbon dioxide concentration measurement value of the initial segment, and the sum of the actual carbon dioxide concentration measurement value of the initial segment and the second concentration compensation value is the actual carbon dioxide concentration value of the initial segment. This value has high accuracy and real-time performance and can be used as the current actual carbon dioxide concentration in the greenhouse, providing a basis for the precise adjustment of the carbon dioxide concentration in the greenhouse.

[0083] This invention installs a cooler 1 inside the collection tube 3 of the air collector to cool and dehumidify the intake of high-humidity air, causing water vapor to condense. The condensate dissolves some carbon dioxide. The second concentration compensation value of this invention is based on the amount of carbon dioxide dissolved in the condensate and the amount of air collected, compensating for the actual measured value of the initial carbon dioxide concentration to obtain the actual concentration of the initial segment, thus improving the accuracy of the actual carbon dioxide concentration in the initial segment. Specifically, the second concentration compensation value in this invention includes the following calculation steps:

[0084] S31, using the cross-sectional area of ​​the end section of the collection tube 3 (i.e., the airflow channel M corresponding to the end concentration sensor 4) as the flow area, the airflow rate per unit time is determined based on the airflow velocity and flow area in the air collector (airflow rate = airflow velocity × flow area).

[0085] S32, determine the airflow duration based on the airflow velocity of the air sampler; determine the air collection volume of the air sampler based on the airflow rate and airflow duration (air collection volume = airflow rate × airflow duration).

[0086] S33, determine the amount of condensate based on the air collection volume of the air collector and the ambient humidity;

[0087] S34, acquire the temperature of each preset temperature measurement point in the air collector, determine the average temperature in the collection tube 3 based on the multiple measurement point temperatures, and determine the solubility of carbon dioxide based on the average temperature.

[0088] S35. Determine the amount of carbon dioxide dissolved based on the solubility of carbon dioxide and the amount of condensate (amount of carbon dioxide dissolved = solubility of carbon dioxide × amount of condensate).

[0089] S36. Based on the amount of carbon dioxide dissolved and the amount of air collected, determine the second concentration compensation value. The second concentration compensation value = the amount of carbon dioxide dissolved ÷ the amount of air collected.

[0090] In this invention, although the carbon dioxide measurement value monitored by the terminal concentration sensor 4 has high accuracy, it has a lag. This invention determines the time difference of airflow between the two concentration sensors 4 by the flow duration. Based on the time difference and the terminal carbon dioxide measurement concentration value, the first concentration compensation value can be corrected a second time, further improving the accuracy of the actual carbon dioxide concentration value in the initial stage. Specifically, this includes the following:

[0091] b1, acquire several final carbon dioxide concentration measurements from the air collector within a preset sampling time, and determine the actual initial carbon dioxide concentration value corresponding to each final carbon dioxide concentration measurement value.

[0092] b2. Calculate the difference between the measured value of carbon dioxide concentration in each final segment and the actual value of carbon dioxide concentration in the corresponding initial segment to obtain several prediction errors; average these prediction errors to determine the average prediction error.

[0093] b3. The first concentration compensation value is corrected a second time based on the predicted average error to improve accuracy.

[0094] In summary, this invention integrates a temperature sensor 5, a flow rate sensor, and a concentration sensor 4 within the collection tube 3 of an air collector. Three partition blocks and a baffle are installed within the collection tube 3 to divide it and ensure dehumidification. Based on temperature, flow rate, initial carbon dioxide concentration measurements, and final carbon dioxide concentration measurements, a first concentration compensation value and a second concentration compensation value are determined. These values ​​are then used to correct and compensate for the initial carbon dioxide concentration measurement, yielding the actual initial carbon dioxide concentration. This design not only considers the lag in the final carbon dioxide concentration measurement but also takes into account factors such as carbon dioxide dissolution, significantly improving the accuracy of the initial carbon dioxide concentration measurement. It exhibits high test response and enhances the real-time performance of concentration measurement. The actual initial carbon dioxide concentration is the actual carbon dioxide concentration in the greenhouse environment. The carbon dioxide concentration in the greenhouse can be adjusted based on this value to keep it within the optimal growth range for crops, meeting their photosynthetic needs and promoting growth.

[0095] Finally, it should be emphasized that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for monitoring carbon dioxide concentration in a high-humidity environment, characterized in that: The monitoring method employs a carbon dioxide concentration measuring device in a high humidity environment. The high humidity environment carbon dioxide concentration measuring device includes an air collector, a host computer, a controller, and a cooler. The air collector includes a working pump, a collection pipe located at the air inlet of the working pump, a monitoring unit located inside the collection pipe, and a driver for driving the working pump. The cooler is located inside the collection pipe, and a drain hole is provided at the bottom of the collection pipe. Multiple inclined partitions are arranged at intervals inside the collection tube. The multiple partitions are arranged in parallel and divide the collection tube into multiple chambers. The upper or lower part of the partition between two adjacent chambers has a connecting part. The connecting parts of the multiple partitions are staggered vertically, so that the gas flows forward in a deflected manner inside the collection tube. The monitoring unit includes at least two temperature sensors, an airflow sensor for monitoring the airflow velocity inside the collection tube, a concentration sensor for monitoring the carbon dioxide concentration, and a humidity sensor for monitoring the ambient humidity. Each chamber of the collection tube is equipped with one of the temperature sensors, and the initial and final sections of the collection tube are each equipped with one of the concentration sensors. The humidity sensor is installed in a high-humidity environment or at the inlet of the collection tube. Among them, the temperature sensor, concentration sensor, airflow sensor and humidity sensor are all communicatively connected to the controller, the driver and the cooler are communicatively connected to the controller, and the controller is communicatively connected to the host computer. The monitoring method includes the following steps: S1: Obtain the ambient humidity in the high humidity environment. If the ambient humidity is greater than the preset humidity, generate a dehumidification command to cool and dehumidify the high humidity air entering the air collector, so that the water vapor in the high humidity air condenses into liquid water. S2, acquire the airflow velocity, the temperature at the preset temperature measurement point, and the initial carbon dioxide concentration measurement value in the air collector. Use the airflow velocity, the temperature at the measurement point, and the initial carbon dioxide concentration measurement value as the input values ​​of the concentration correction model, and output the first concentration compensation value. S3, determine the second concentration compensation value based on ambient humidity, measuring point temperature and airflow velocity; S4. The carbon dioxide concentration measurement value of the initial segment is corrected and compensated using the first concentration compensation value and the second concentration compensation value to determine the actual carbon dioxide concentration value of the initial segment. S3 includes the following specific contents: S31, using the cross-sectional area of ​​the end of the collection tube as the flow area, the airflow rate per unit time is determined based on the airflow velocity and flow area inside the air collector. S32, determine the airflow duration based on the airflow velocity of the air collector, and determine the air collection volume of the air collector based on the airflow rate and airflow duration; S33, determine the amount of condensate based on the air collection volume of the air collector and the ambient humidity; S34, determine the average temperature inside the air collector based on the temperature of multiple measuring points inside the air collector, and determine the solubility of carbon dioxide based on the average temperature of the air collector. S35, Determine the amount of carbon dioxide dissolved based on the solubility of carbon dioxide and the amount of condensate. S36, Determine the second concentration compensation value based on the amount of carbon dioxide dissolved and the amount of air collected; The monitoring method further includes a secondary correction of the first concentration compensation value, which includes the following: b1, acquire several final carbon dioxide concentration measurements from the air collector within a preset sampling time, and determine the actual initial carbon dioxide concentration value corresponding to each final carbon dioxide concentration measurement value. b2. Calculate the difference between the measured value of carbon dioxide concentration in each final segment and the actual value of carbon dioxide concentration in the corresponding initial segment to obtain several prediction errors. Determine the average prediction error based on these prediction errors. b3, the first concentration compensation value is corrected a second time based on the predicted average error.

2. The method for monitoring carbon dioxide concentration in a high-humidity environment according to claim 1, characterized in that: The separator has a mounting groove, the cooler is a semiconductor cooling chip disposed in the mounting groove, the cold surface of the cooler is covered with a heat-conducting layer, and a heat dissipation cavity is opened on the separator corresponding to the other side of the cooler. The heat dissipation cavity is connected to the output end of the working pump through a connecting branch pipe.

3. The method for monitoring carbon dioxide concentration in a high-humidity environment according to claim 1, characterized in that: The construction of the concentration correction model in step S2 includes the following: S21. Under preset experimental conditions, collect a sample of carbon dioxide concentration measurements in the initial segment within a preset test duration; the preset experimental conditions include preset initial segment carbon dioxide concentration, preset humidity, and preset airflow velocity. S22, calculate the initial segment carbon dioxide concentration deviation based on the measured value of the initial segment carbon dioxide concentration and the preset initial segment carbon dioxide concentration; S23, adjust any one or more of the preset carbon dioxide concentration, preset humidity and preset airflow speed to obtain several initial segment carbon dioxide concentration measurement values ​​and their corresponding initial segment carbon dioxide concentration deviations. Use the preset experimental conditions and several initial segment carbon dioxide concentration measurement values ​​as input data, input them into the recurrent neural network, and obtain the prediction results. S24, compare the predicted result with the initial carbon dioxide concentration deviation corresponding to the initial carbon dioxide concentration measurement value, and calculate the loss value of the loss function of the recurrent neural network; S25, update the parameters of the recurrent neural network according to the loss value of the loss function, and iteratively train the recurrent neural network until it converges to obtain a trained recurrent neural network, which is then used as the concentration correction model.

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