ANTI-CONDENSATION RADIANT COOLING SYSTEM AND CONTROL METHOD THEREOF

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 (a) to Chinese Patent Application No. 202411209128.9, filed on Aug. 30, 2024, which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to a technical field of radiant cooling system, in particular to an anti-condensation radiant cooling system and control method thereof.

BACKGROUND ART

Radiant cooling technology has a wide application prospect and serves as a solution for cooling and thermal comfort. The inventors have found that conventional radiant cooling systems suffer from limited cooling capacity per unit area and a high risk of surface condensation. The cooling capacity of the radiant cooling system is restricted by an ambient dew point temperature, which limits large-scale promotion and application of the radiant cooling technology to some extent.

Conventionally speaking, materials with high infrared transmittance may be used to physically isolate a surface of the radiant cooling panel from indoor hot and humid air, thereby avoiding a risk of condensation on the surface of the radiant cooling panel while still maintaining effective radiant heat exchange between the radiant cooling panel and indoor occupants.

The conventional radiant cooling systems adopt a design of “a radiant cooling terminal plus a DOAS.” To prevent condensation on the surface of the radiant cooling terminal, chilled water at a high-temperature of 15° C. is typically used as the cooling source. Meanwhile, the dedicated outdoor air system (DOAS) is responsible for handling the indoor moisture load and requires chilled water at a low-temperature of 7° C. for dehumidification. As a result, two separate chilled water systems are needed to meet different temperature requirements for the chilled water, which increases the complexity and cost of the overall system.

On the other hand, the radiant cooling technology primarily relies on radiative heat exchange at the surface of the radiant cooling panel and inherently features a slow response speed. For example, a cooling medium (e.g., water) within the radiant cooling panel releases cooling capacity to an indoor space via the surface of the radiant cooling panel. This process is affected by multiple factors such as an indoor temperature distribution. Due to an inherent thermal inertia of radiative heat transfer, the radiant cooling technology cannot respond quickly when there is a rapid change in indoor conditions, such as a sudden increase or decrease in the number of occupants, which causes a sharp change in the cooling load and makes it difficult for the radiant cooling terminal (RCT) to respond in time, thereby affecting a thermal comfort experience of occupants.

SUMMARY

The present disclosure provides an anti-condensation radiant cooling system and control method thereof, which enables efficient cooling while ensuring thermal comfort. On the one hand, by allowing the radiant cooling temperature to be lower than the ambient dew point, the risk of condensation is reduced while increasing the cooling capacity per unit area. On the other hand, the system can rapidly respond to changes in indoor occupant status and promptly meet thermal comfort needs of occupants, thereby providing a more comfortable and healthier indoor environment.

According to a first aspect of the present disclosure, a control method for an anti-condensation radiant cooling system is proposed. The anti-condensation radiant cooling system comprises an anti-condensation radiant cooling device and an indoor status parameter monitoring device. The anti-condensation radiant cooling device comprises an anti-condensation radiant cooling device and a DOAS, and the anti-condensation radiant cooling device comprises a radiant cooling panel and an infrared-transparent material layer. A side of the infrared-transparent material layer opposite to the radiant cooling panel serves as an air contact surface, a sealed interlayer is provided between the air contact surface and the radiant cooling panel, and the sealed interlayer has an interior filled with a vacuum or a dry gas.

In accordance with some embodiments, the indoor status parameter monitoring device comprises a thermal camera and a temperature-humidity sensor, the thermal camera being configured to acquire real-time temperature matrix data of indoor thermal images, and the temperature-humidity sensor being configured to acquire an indoor air temperature fa and a relative humidity (RH) in real time.

In accordance with some embodiments, the control method comprises the following comfort-oriented control steps after the anti-condensation radiant cooling device is turned on:

• • step 1: acquiring the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH); and preprocessing the temperature matrix data of indoor thermal images, wherein preprocessing the temperature matrix data of indoor thermal images comprises setting a reference temperature range for a human body surface temperature, and performing an element-by-element evaluation on a pixel temperature matrix of the temperature matrix data of indoor thermal images corresponding to a human activity area, wherein when a first matrix element has a temperature value within the reference temperature range for the human body surface temperature, the first matrix element is grouped into a human body surface temperature dataset, and an average value of matrix elements in the dataset is calculated and stored as a human body surface temperature t_ob;
  • step 2: performing a personnel counting based on the temperature matrix data of indoor thermal images to obtain a number N of indoor occupants; calculating an air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants; calculating a real-time indoor dew point temperature t_d based on the indoor air temperature t_a and the relative humidity (RH); and calculating a minimum required fresh air volume Q for indoor occupants based on the number N of indoor occupants;
  • step 3: determining a condensation risk by determining whether the air contact surface temperature t_m is greater than a real-time indoor dew point threshold, the indoor dew point threshold being defined as the real-time indoor dew point temperature t_d plus a margin value σ:
  • if the air contact surface temperature t_m is greater than the real-time indoor dew point threshold, proceeding to step 4,
  • if the air contact surface temperature t_m is not greater than the real-time indoor dew point threshold, controlling the DOAS to operate at a highest airflow setting, and returning to the step 1; and
  • step 4: calculating a predicted mean vote (PMV) value under current indoor conditions based on the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH), and determining whether the PMV value is greater than a first threshold:
  • if the PMV value is greater than the first threshold, calculating a proportion of matrix elements in the human body surface temperature dataset whose temperature values are greater than the human body surface temperature t_ob, and determining whether the proportion is greater than a second threshold:
    • if the proportion is greater than the second threshold, controlling the DOAS to operate at a highest airflow setting, ending a current control action process, and returning to the step 1; and
    • if the proportion is less than or equal to the second threshold, controlling the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, while increasing a cooling output of the radiant cooling panel, ending the current control action process, and returning to the step 1;
  • if the PMV value is not greater than the first threshold, controlling the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, and further determining whether the PMV value is less than a third threshold:
    • if the PMV value is less than the third threshold, reducing a cooling output of the radiant cooling panel, and returning to the step 1; and
    • if the PMV value is greater than or equal to the third threshold, returning to the step 1.

According to some embodiments, preprocessing the temperature matrix data of indoor thermal images further comprises:

• • setting a reference temperature range for a surface temperature of the radiant cooling panel, a reference temperature range for an inner surface temperature of an exterior wall, and a reference temperature range for interior walls and other surfaces;
  • performing the element-by-element evaluation on the temperature matrix data of indoor thermal images corresponding to areas excluding the human activity area, wherein when a second matrix element has a temperature value within the reference temperature range for the inner surface of the exterior wall, the second matrix element is grouped into an exterior wall inner surface temperature dataset, wherein when a third matrix element has a temperature value within the reference temperature range for interior walls and other surfaces, the third matrix element is grouped into an interior wall and other surface temperature dataset, and wherein when a fourth matrix element has a temperature value within the reference temperature range for the surface of the radiant cooling panel, the fourth matrix element is grouped into a radiant cooling panel surface temperature dataset.

According to some embodiments, preprocessing the temperature matrix data of indoor thermal images further comprises:

• • performing the element-by-element evaluation on the temperature matrix data of indoor thermal images, wherein when a fifth matrix element has a temperature value outside a preset range including the reference temperature range for the human body surface, the reference temperature range for the surface of the radiant cooling panel, the reference temperature range for the inner surface of the exterior wall and the reference temperature range for interior walls and other surfaces, the fifth matrix element is marked as an abnormal temperature point;
  • calculating a proportion of the abnormal temperature point relative to all matrix elements in the temperature matrix data of indoor thermal images; and setting an upper threshold value a for the proportion of the abnormal temperature point, wherein when the proportion of the abnormal temperature point is less than the upper threshold value a, the fifth matrix element marked as the abnormal temperature point is removed as abnormal data, and wherein when the proportion of the abnormal temperature point is greater than or equal to the upper threshold value a, a warning indicating an anomaly in detection by the thermal camera is issued.

According to some embodiments, performing the personnel counting based on the temperature matrix data of indoor thermal images to obtain the number N of indoor occupants comprises:

• • setting a counting line at a coordinate position corresponding to a door position in the temperature matrix data of indoor thermal images corresponding to areas covering an entry/exit pathway of a room based on the human body surface temperature dataset;
  • defining two opposite vectors perpendicular to the counting line to represent directions for entering and exiting the room, respectively;
  • extracting the human body surface temperature dataset and a corresponding coordinate set over consecutive frames; and
  • comparing an offset of the coordinate set with respect to preset vector directions of the two opposite vectors to determine and record an exiting behavior and an entering behavior of a person represented by one of the two opposite vectors, and cumulatively counting the exiting behavior and the entering behavior to obtain the number N of indoor occupants.

According to some embodiments, calculating the air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants comprising:

• • calculating an average value of matrix elements in the radiant cooling panel surface temperature dataset and storing the average value as a radiant cooling panel surface temperature t_{r_c},
  • calculating an average value of matrix elements in the exterior wall inner surface temperature dataset and storing the average value as t_{r_out},
  • calculating an average value of matrix elements in the interior wall and other surface temperature dataset and storing the average value as t_{r_in},
  • calculating an average radiant temperature t_r of an indoor environment by the following formula:

t r _ = t r ⁢ _ ⁢ in ⁢ A in + t r ⁢ _ ⁢ out ⁢ A out + t r ⁢ _ ⁢ c ⁢ A c A in + A out + A c ,

• • where A_in is an area of interior walls and other surfaces, A_out is an area of exterior walls, and A_c is a surface area of the radiant cooling panel;
    • calculating an equivalent average radiant temperature t_{r_h} of non-cooled surfaces when the indoor occupants are present by the following formula:

t r ⁢ _ ⁢ h _ = t r ⁢ _ ⁢ in ⁢ A in + t r ⁢ _ ⁢ out ⁢ A out + t ob ⁢ A ob A in + A out + A ob ,

• • where A_ob represents an effective radiating area of the indoor occupants, calculated by the following formula:

A ob = A h × N - f d × A h × ( N - 1 ) ,

• • • where A_h is an effective radiating area per person with a value of 1.49 m², N is the number of indoor occupants, and f_d is a shading coefficient with a value of 0.48;
  • calculating the air contact surface temperature t_m of the infrared-transparent material layer based on the equivalent average radiant temperature t_{r_h} and the radiant cooling panel surface temperature t_{r_c} by the following formula:

T m 4 = T r ⁢ _ ⁢ c 4 + 10 8 × f z × f m × ( t r ⁢ _ ⁢ h _ - t r ⁢ _ ⁢ c ) ,

• • where T_m is a thermodynamic temperature at an air contact surface of the infrared-transparent material layer, where T_m=t_m+273.15. T_{r_c} is a thermodynamic temperature at a surface of the radiant cooling panel, where; f_z is a comprehensive radiative heat transfer coefficient with a value of 1.1, and f_m is a radiative heat transfer coefficient of a semitransparent medium, which is related to thermal radiation characteristics of the infrared-transparent material layer; when a transmittance of the infrared-transparent material layer is 0.9, f_m has a value of 0.67; when the transmittance is 0.85, f_m has a value of 0.36; when the transmittance is 0.8, f_m has a value of 0.25; and when the transmittance is 0.7, f_m has a value of 0.15.

According to some embodiments, the control method further comprises performing an indoor pre-dehumidification before the anti-condensation radiant cooling device is turned on, wherein performing the indoor pre-dehumidification comprises:

• • calculating an initial indoor dew point temperature t_d0 based on the indoor air temperature t_a and the relative humidity (RH);
  • setting a safety upper temperature limit t_m0, and determining whether the initial indoor dew point temperature t_d0 is less than the safety upper temperature limit t_m0;
  • if the initial indoor dew point temperature t_d0 is less than the safety upper temperature limit t_m0, controlling the anti-condensation radiant cooling device to turn on;
  • if the initial indoor dew point temperature t_d0 is not less than the safety upper temperature limit t_m0, controlling the DOAS to operate at a highest airflow level, and once a real-time indoor dew point temperature t_a becomes less than the safety upper temperature limit t_m0, controlling the anti-condensation radiant cooling device to turn on.

According to some embodiments, the real-time indoor dew point temperature t_a and the initial indoor dew point temperature t_d0 are output by using a psychrometric chart tool based on the indoor air temperature t_a and the relative humidity (RH).

According to some embodiments, the step 4 further comprises calculating the predicted mean vote (PMV) value under current indoor conditions based on the average radiant temperature t_r, the human body surface temperature t_ob, the indoor air temperature t_a, and the relative humidity (RH); wherein a thermal comfort PMV evaluation model is defined as a function mapping: PMV=f(M, t_ob, t_a, RH, and t_r), where M is a human metabolic rate.

According to some embodiments, in the step 2, the minimum required fresh air volume Q based on the number N of occupants for indoor occupants is calculated using the following formula:

Q = q × N ,

• • where q is a minimum fresh air volume per person, where q is taken as 30 m³/(h·person) for offices, 11-14 m³/(h·person) for meeting rooms, and 22-28 m³/(h·person) for classrooms.

A second aspect of the present disclosure proposes an anti-condensation radiant cooling system, comprising an anti-condensation radiant cooling device, an indoor status parameter monitoring device, and a control system. The anti-condensation radiant cooling device comprises an anti-condensation radiant cooling device and a DOAS. the anti-condensation radiant cooling device comprises a radiant cooling panel and an infrared-transparent material layer; a side of the infrared-transparent material layer opposite to the radiant cooling panel serves as an air contact surface, and a sealed interlayer is provided between the air contact surface and the radiant cooling panel, the sealed interlayer having an interior filled with a vacuum or a dry gas.

In some embodiments, the indoor status parameter monitoring device comprises a thermal camera and a temperature-humidity sensor; the thermal camera is configured to acquire real-time temperature matrix data of indoor thermal images, and the temperature-humidity sensor is configured to acquire an indoor air temperature t_a and a relative humidity (RH) in real-time.

In some embodiments, the control system is configured to perform the steps of the control method, and the control system comprises a computation processing module and an execution module. The computation processing module comprises a preprocessing unit, a temperature statistics unit, an occupant counting unit, a PMV calculation model, and a comprehensive heat transfer model.

In some embodiments, the preprocessing unit is configured to acquire the temperature matrix data of indoor thermal images and preprocess the data by setting a reference temperature range for a human body surface temperature and performing an element-by-element evaluation on a pixel temperature matrix of the temperature matrix data of indoor thermal images corresponding to a human activity area, such that when a matrix element has a temperature value within the reference range for the human body surface temperature, the matrix element is grouped into a human body surface temperature dataset.

In some embodiments, the occupant counting unit is configured to perform an occupant counting based on the temperature matrix data of indoor thermal images to obtain a number N of indoor occupants, and to calculate a minimum required fresh air volume Q for indoor occupants based on the number N of indoor occupants.

In some embodiments, the temperature statistics unit is configured to calculate an average value of matrix elements in the human body surface temperature dataset and store the average value as a human body surface temperature t_ob.

In some embodiments, the PMV calculation model is configured to calculate a PMV value under current indoor conditions based on the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH).

In some embodiments, the comprehensive heat transfer model is configured to calculate an air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants, and to obtain the indoor air temperature t_a and the relative humidity (RH), and to calculate a real-time indoor dew point temperature t_d based on the indoor air temperature t_a and the relative humidity (RH).

In some embodiments, the execution module is configured to, after the anti-condensation radiant cooling device is turned on, perform the following comfort-oriented control steps based on parameters processed by the computation processing module:

• • determining a condensation risk by determining whether the air contact surface temperature t_m is greater than a real-time indoor dew point threshold, the threshold being defined as the real-time indoor dew point temperature t_d plus a margin value σ;
  • if the air contact surface temperature t_m is not greater than the real-time indoor dew point threshold, the execution module is configured to control the DOAS to operate at a highest airflow level, and to trigger a next round of the control steps based on parameters calculated and processed in real time by the computation processing module;
  • if the air contact surface temperature t_m is greater than the real-time indoor dew point threshold, the execution module is configured to determine whether the PMV value is greater than a first threshold value:
  • if the PMV value is greater than the first threshold, the execution module is configured to calculate a proportion of matrix elements in the human body surface temperature dataset whose temperature values are greater than the human body surface temperature t_ob, and determine whether the proportion is greater than a second threshold:
  • if the proportion is less than or equal to the second threshold, the execution module is configured to control the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, while increasing a cooling output of the radiant cooling panel, to end a current control action process, and to trigger the next round of the control steps based on parameters calculated and processed in real time by the computation processing module;
  • if the proportion is greater than the second threshold, the execution module is configured to control the DOAS to operate at a highest airflow level, to end the current control action process, and to trigger the next round of the control steps based on parameters calculated and processed in real time by the computation processing module;
  • if the PMV value is less than or equal to the first threshold, the execution module is configured to control the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, and to further determine whether the PMV value is less than a third threshold:
  • if the PMV value is less than the third threshold, the execution module is configured to reduce a cooling output of the radiant cooling panel, and to trigger the next round of the control steps based on parameters calculated and processed in real time by the computation processing module;
  • if the PMV value is greater than or equal to the third threshold, the execution module is configured to trigger the next round of the control steps based on parameters calculated and processed in real time by the computation processing module.

The anti-condensation radiant cooling system, implemented using the control method described in the foregoing embodiments, on the one hand, allow a radiant cooling temperature to be lower than an ambient dew point, thereby eliminating a risk of condensation while effectively enhancing the cooling capacity per unit area. On the other hand, the anti-condensation radiant cooling system can rapidly respond to changes in indoor occupant status to promptly meet thermal comfort needs of occupants. At the same time, the system enables a radiant cooling terminal and a DOAS to share chilled water at a same temperature, that is, to operate using a single chilled water unit, which simplifies the system structure, reduces cost, and provides users with a more comfortable and healthier indoor environment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart illustrating comfort-oriented control steps of a control method according to some embodiments of the present disclosure;

FIG. 2 is a flow chart illustrating indoor pre-dehumidification steps of the control method according to some embodiments of the present disclosure;

FIG. 3 is a schematic structural diagram of an anti-condensation radiant cooling device of an anti-condensation radiant cooling system according to some embodiments of the present disclosure;

FIG. 4 is a schematic block diagram of module composition of a control system of the anti-condensation radiant cooling system according to some embodiments of the present disclosure;

FIG. 5 is a schematic diagram of an image acquired by a thermal camera of an indoor status parameter monitoring device of the anti-condensation radiant cooling system according to some embodiments of the present disclosure;

FIG. 6 is a thermal image of L*H dimensions representing temperature matrix data acquired by the thermal camera of the indoor status parameter monitoring device of the anti-condensation radiant cooling system according to some embodiments of the present disclosure.

DETAILED DESCRIPTION

Exemplary embodiments are illustrated in the accompanying drawings, in which like or similar reference numerals consistently represent like or similar elements or elements having like or similar functions throughout the drawings. The embodiments described below with reference to the drawings are provided as examples only and are intended to illustrate, but not to limit, the scope of the present disclosure.

FIG. 1 shows a control method for an anti-condensation radiant cooling system. In some embodiments, the anti-condensation radiant cooling system comprises an anti-condensation radiant cooling device and an indoor status parameter monitoring device; the anti-condensation radiant cooling device comprises an anti-condensation radiant cooling device and a DOAS, and the anti-condensation radiant cooling device comprises a radiant cooling panel and an infrared-transparent material layer; a side of the infrared-transparent material layer opposite to the radiant cooling panel serves as an air contact surface, and a sealed interlayer is provided between the air contact surface of the infrared-transparent material layer and the radiant cooling panel, and the sealed interlayer having an interior filled with a vacuum or a dry gas.

In some embodiments, the indoor status parameter monitoring device comprises a thermal camera and a temperature-humidity sensor, the thermal camera being configured to acquire real-time temperature matrix data of indoor thermal images, and the temperature-humidity sensor being configured to acquire a real-time indoor air temperature fa and a relative humidity (RH).

According to various embodiments, the control method comprising the following comfort-oriented control steps after the anti-condensation radiant cooling device is turned on:

• • step 1: acquiring temperature matrix data of indoor thermal images, an indoor air temperature t_a, and a relative humidity (RH); preprocessing the temperature matrix data of indoor thermal images, wherein preprocessing the temperature matrix data of indoor thermal images comprises setting a reference temperature range for a human body surface temperature, and performing an element-by-element evaluation on a pixel temperature matrix of the temperature matrix data of indoor thermal images corresponding to a human activity area, wherein when a matrix element has a temperature within the reference temperature range for the human body surface temperature, the matrix element is grouped into a human body surface temperature dataset Temp.Data_object, and an average value of matrix elements in the human body surface temperature dataset Temp.Data_object is calculated and stored as a human body surface temperature t_ob;
  • step 2: performing a personnel counting based on the temperature matrix data of indoor thermal images to obtain a number N of indoor occupants; calculating an air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants; calculating a real-time indoor dew point temperature t_d based on the indoor air temperature t_a and the relative humidity (RH); and calculating a minimum required fresh air volume Q for indoor occupants based on the number N of indoor occupants;
  • step 3: determining a condensation risk by determining whether the air contact surface temperature t_m is greater than a real-time indoor dew point threshold, the indoor dew point threshold being defined as the real-time indoor dew point temperature t_d plus a margin value σ, wherein the margin value σ may be set according to actual needs. In some examples, according to the requirements of JGJ142-2012, a supply water temperature of a radiant cooling system shall ensure that a surface temperature for cooling is 1-2° C. higher than the indoor air dew point temperature. Therefore, the value of σ ranges from 1 to 2, and, for example, σ may be set to 1;
  • if the air contact surface temperature t_m is greater than the real-time indoor dew point threshold, proceeding to step 4;
  • if the air contact surface temperature t_m is not greater than the real-time indoor dew point threshold, controlling the DOAS to operate at a highest airflow setting, and returning to the step 1; and
  • step 4: calculating a predicted mean vote (PMV) value under current indoor conditions based on the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH), and determining whether the PMV value falls within a thermal comfort range, i.e., whether the PMV value is greater than a first threshold value, and, for example, the first threshold value may be set to 1:
  • if the PMV value is greater than the first threshold, calculating a proportion of matrix elements in the human body surface temperature dataset Temp.Data_object whose temperature values are greater than the human body surface temperature t_ob, and determining whether the proportion is greater than a second threshold, and, for example, the second threshold may be set to 50%:
    • if the proportion is greater than the second threshold, controlling the DOAS to operate at a highest airflow setting, ending a current control action process, and returning to the step 1; and
  • if the proportion is less than or equal to the second threshold, controlling the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, while increasing a cooling output of the radiant cooling panel, ending the current control action process, and returning to the step 1;
  • if the PMV value is not greater than the first threshold, controlling the DOAS to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, and further determining whether the PMV value is less than a third threshold, and, for example, the third threshold may be set to −1:
    • if the PMV value is less than the third threshold, reducing a cooling output of the radiant cooling panel, and returning to the step 1; and
    • if the PMV value is greater than or equal to the third threshold, ending the current control action process and returning to step 1.

According to one or more embodiments, the infrared-transparent material layer is used to isolate a surface of the radiant cooling panel from indoor air. As a result, a surface temperature of the radiant cooling panel is no longer directly constrained by an ambient dew point temperature, allowing the characteristics of radiant cooling and potential condensation to be controlled independently. This enables enhancement of the cooling capacity per unit area of a radiant cooling terminal by means of low-temperature cooling, while eliminating the risk of condensation.

To eliminate a risk of indoor condensation, various embodiments of the present disclosure employ an control based on a built-in comprehensive heat transfer model computation module. By comprehensively considering real-time states of various indoor surfaces and active occupants, the system determines whether condensation risk exists by comparing a computed air contact surface temperature t_m and the real-time indoor dew point temperature t_d. When the air contact surface temperature t_m is less than or equal to the real-time indoor dew point threshold, condensation risk is deemed to exist. In such cases, a dedicated outdoor air system is controlled to operate at a highest airflow setting to deliver a greater volume of low-temperature, low-humidity fresh air into the room, thereby rapidly reducing an indoor air humidity and eliminating the risk of condensation.

Due to an inherent thermal inertia of the radiant cooling heat transfer mechanism, when indoor operating conditions change rapidly, such as a sudden increase or decrease in the number of occupants, or a rapid rise in a body surface temperature of the occupants, the radiant cooling terminal may not be able to respond quickly to the change in cooling load, potentially affecting a thermal comfort experience of occupants. The present disclosure implements a comfort-oriented intelligent control, whereby a predicted mean vote (PMV) value under the current indoor conditions is calculated based on the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH), and it is determined whether the PMV falls within a thermal comfort range.

When PMV>1, the system considers that the occupants are in an overheated state. In this case, the system further calculates a proportion of matrix elements in the human body surface temperature dataset Temp.Data_object that are greater than the average body surface temperature t_ob, and determines whether the proportion is greater than a second threshold. If the proportion is greater than the second threshold, it is considered that most occupants have relatively high body surface temperatures, which may be due to a large number of people entering the indoor space from a high-temperature outdoor environment. At this point, the DOAS is controlled to operate at a highest airflow setting to deliver more low-temperature, low-humidity fresh air into the indoor space, thereby quickly reducing the indoor air temperature and meeting occupants' thermal comfort needs. If the proportion is less than or equal to the second threshold, it is considered that only a small portion of the occupants have relatively high body surface temperatures. In this case, there is no urgent need for a rapid reduction in indoor temperature. The cooling demand is primarily met by the radiant cooling terminal adjusting its output to accommodate a load change, while the DOAS only needs to supply a minimum required fresh air volume Q for indoor occupants. Accordingly, the DOAS is controlled to adjust its airflow to the setting corresponding to Q, avoiding excessive airflow that may compromise comfort (as excessive airflow from the DOAS can negatively affect user comfort by causing symptoms such as dryness or headaches). At the same time, the radiant cooling panel is controlled to increase its cooling output.

When PMV≤1, it is determined that the occupants are not in an overheated state. The DOAS is then controlled to adjust its airflow to a level corresponding to a minimum required fresh air volume Q for indoor occupants.

When −1≤PMV≤1, the environment is considered to be generally comfortable for the occupants. And when PMV<−1, the occupants are considered to be in an overcooled state, and a cooling output of the radiant cooling panel is reduced accordingly to lower an overall cooling capacity of the system, in order to meet thermal comfort requirements of the occupants.

The control method according to the present disclosure, on the one hand, allows a radiant cooling temperature to be lower than an ambient dew point temperature, thereby eliminating a risk of condensation while effectively enhancing the cooling capacity per unit area of a radiant terminal. On the other hand, it enables the system to promptly meet thermal comfort needs of occupants when changes occur in indoor occupant status. This avoids discomfort caused by the thermal inertia of the radiant cooling terminal that makes it difficult to respond quickly to load changes, and provides users with a more comfortable and healthier indoor environment.

According to one or more embodiments, preprocessing the temperature matrix data of indoor thermal images in the step 1 further comprises:

• • setting a reference temperature range for a surface temperature of the radiant cooling panel, a reference temperature range for an inner surface temperature of an exterior wall, and a reference temperature range for interior walls and other surfaces.

It should be noted that the inner surface of the exterior wall refers to the surface of the wall that is in contact with an outdoor environment and faces an interior space, i.e., the wall has one side facing the interior and the other side facing the exterior. The term “interior wall” refers to a wall with both sides facing indoor spaces. The term “other surfaces” in the phrase “interior walls and other surfaces” refer to the surfaces of indoor furniture such as tables, chairs, cabinets, and similar items.

According to some examples, the above temperature reference ranges are set as shown in Table 1 below:

TABLE 1
Temperature Reference Range Settings

	Temperature Region	Reference Range (° C.)
	Human body surface	(28.0, 35.5]
	Radiant cooling panel surface	(7.0, 20.0]
	Inner surface of exterior wall	(28.0, 40.0]
	Interior walls and other surfaces	(20.0, 28.0]

According to one or more embodiments, preprocessing the temperature matrix data of indoor thermal images in the step 1 further comprises:

• • comparing the temperature matrix data of indoor thermal images with preset temperature reference ranges, and grouping the temperature matrix data of indoor thermal images into corresponding temperature datasets, including:
  • performing the element-by-element evaluation on the temperature matrix data of indoor thermal images corresponding to areas excluding the human activity area, wherein when a matrix element has a temperature value within the reference temperature range for the inner surface of the exterior wall, the matrix element is grouped into an exterior wall inner surface temperature dataset Temp.Data_ex. wall, when a matrix element has a temperature value within the reference temperature range for interior walls and other surfaces, the matrix element is grouped into an interior wall and other surface temperature dataset Temp.Data_in. wall, and when a matrix element has a temperature value within the reference temperature range for the surface of the radiant cooling panel, the matrix element is grouped into a radiant cooling panel surface temperature dataset Temp.Data_cooling.

According to one or more embodiments, preprocessing the temperature matrix data of indoor thermal images further comprises:

• • performing the element-by-element evaluation on the temperature matrix data of indoor thermal images, wherein when a matrix element has a temperature value outside a preset range including the reference temperature range for the human body surface, the reference temperature range for the surface of the radiant cooling panel, the reference temperature range for the inner surface of the exterior wall and the reference temperature range for interior walls and other surfaces, the matrix element is marked as an abnormal temperature point;
  • calculating a proportion of the abnormal temperature point relative to all matrix elements in the temperature matrix data of indoor thermal images; and
  • setting an upper threshold value a for the proportion of the abnormal temperature point,
    • wherein when the proportion of the abnormal temperature point is less than a preset upper threshold value a, the matrix element marked as the abnormal temperature point as abnormal data is removed, thereby improving the accuracy of calculating the air contact surface temperature t_m, and enhancing the accuracy of condensation risk determination (CRD); and
    • wherein when the proportion of the abnormal temperature point is greater than or equal to the upper threshold a, issuing a warning indicating an anomaly in detection by the thermal camera, so that any abnormality in the comfort-oriented control can be detected in a timely manner.

According to one or more embodiments, in the step 2, performing the personnel counting based on the temperature matrix data of indoor thermal images to obtain the number N of indoor occupants comprises:

• • setting a counting line at a coordinate position corresponding to a door position in the temperature matrix data of indoor thermal images corresponding to areas covering an entry/exit pathway of a room based on the human body surface temperature dataset Temp.Data_object;
  • defining two opposite vectors perpendicular to the counting line to represent directions for entering and exiting the room, respectively;
  • extracting the human body surface temperature dataset and a corresponding coordinate set over consecutive frames; and
  • comparing an offset of the coordinate set with respect to preset vector directions of the two opposite vectors to determine and record an exiting behavior and an entering behavior of a person represented by one of the two opposite vectors, and cumulatively counting the exiting behavior and the entering behavior to obtain the number N of indoor occupants.

According to one or more embodiments, in the step 2, calculating the air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants comprising:

• • calculating an average value of matrix elements in the radiant cooling panel surface temperature dataset Temp.Data_cooling and storing the average value as a radiant cooling panel surface temperature t_{r_c};
  • calculating an average value of matrix elements in the exterior wall inner surface temperature dataset Temp.Data_ex.wall and storing the average value as t_{r_out},
  • calculating an average value of matrix elements in the interior wall and other surface temperature dataset Temp.Data_in.wall and storing the average value as t_{r_in};
  • calculating an average radiant temperature t_r of an indoor environment by the following formula:

t r _ = t r ⁢ _ ⁢ in ⁢ A in + t r ⁢ _ ⁢ out ⁢ A out + t r ⁢ _ ⁢ c ⁢ A c A in + A out + A c ,

• • where A_in is an area of interior walls and other surfaces, A_out is an area of exterior walls, and A_c is a surface area of the radiant cooling panel; these values depend on specific conditions of a room and are input as basic preset parameters;
    • calculating an equivalent average radiant temperature t_{r_h} of non-cooled surfaces when the indoor occupants are present by the following formula:

t r ⁢ _ ⁢ h _ = t r ⁢ _ ⁢ in ⁢ A in + t r ⁢ _ ⁢ out ⁢ A out + t ob ⁢ A ob A in + A out + A ob ,

• • where A_ob represents an effective radiating area of the indoor occupants, calculated by the following formula:

A ob = A h × N - f d × A h × ( N - 1 ) ,

• • where A_h is an effective radiating area per person with a value of 1.49 m² according to GB/T 10000-1988: Chinese Adult Human Body Dimensions, N is the number of indoor occupants, and f_d is a shading coefficient with a value of 0.48;
  • calculating the air contact surface temperature t_m of the infrared-transparent material layer based on the equivalent average radiant temperature t_{r_h} and the radiant cooling panel surface temperature t_{r_c} by the following formula:

T m 4 = T r ⁢ _ ⁢ c 4 + 10 8 × f z × f m × ( t r ⁢ _ ⁢ h _ - t r ⁢ _ ⁢ c ) ,

• • where T_m is a thermodynamic temperature (in Kelvin) at an air contact surface of the infrared-transparent material layer, where T_m=t_m+273.15. T_{r_c} is a thermodynamic temperature (in Kelvin) at a surface of the radiant cooling panel, where T_{r_c}=t_{r_c}+273.15; f_z, which is related to the surface emissivity of the various surfaces, is a comprehensive radiative heat transfer coefficient; for typical public buildings, f_z has a value of 1.1, and f_m is a radiative heat transfer coefficient of a semitransparent medium, which is related to thermal radiation characteristics of the infrared-transparent material layer; when a transmittance of the infrared-transparent material layer is 0.9, f_m has a value of 0.67; when the transmittance is 0.85, f_m has a value of 0.36; when the transmittance is 0.8, f_m has a value of 0.25; and when the transmittance is 0.7, f_m has a value of 0.15.

According to one or more embodiments, as shown in FIG. 2, the control method further comprises performing an indoor pre-dehumidification before the anti-condensation radiant cooling device is turned on, performing the indoor pre-dehumidification comprising:

• • calculating an initial indoor dew point temperature t_d0 based on the indoor air temperature t_a and the relative humidity (RH);
  • setting a safety upper temperature limit t_m0, wherein the safety upper temperature limit t_m0 is defined as the air contact surface temperature t_m calculated when the surface temperature t_{r_c} of the radiant cooling panel is 7° C., for example; and determining whether the initial indoor dew point temperature t_d0 is less than the safety upper temperature limit t_m0;
  • if the initial indoor dew point temperature t_d0 is less than the safety upper temperature limit t_m0, controlling the anti-condensation radiant cooling device to turn on; and
  • if the initial indoor dew point temperature t_d0 is not less than the safety upper temperature limit t_m0, controlling the DOAS to operate at a highest airflow level, and once a real-time indoor dew point temperature t_a becomes less than the safety upper temperature limit t_m0, controlling the anti-condensation radiant cooling device to turn on.

Before the anti-condensation radiant cooling device is turned on, when an initial indoor dew point temperature t_d0 is greater than or equal to the safety upper temperature limit t_m0, there is a risk of condensation. In this case, the DOAS is controlled to operate at a highest airflow setting to introduce relatively dry fresh air, which can effectively reduce the indoor air humidity, thereby avoiding the risk of condensation and preventing condensation problems caused by excessive indoor humidity.

According to one or more embodiments, in the step 2 and in the steps of performing the indoor pre-dehumidification, the real-time indoor dew point temperature t_a and the initial indoor dew point temperature t_d0 are output by using a psychrometric chart tool based on the indoor air temperature t_a and the relative humidity (RH).

According to one or more embodiments, the step 4 further comprises calculating the predicted mean vote (PMV) value under current indoor conditions based on the average radiant temperature t_r, the human body surface temperature t_ob, the indoor air temperature t_a, and the relative humidity (RH); wherein a thermal comfort PMV evaluation model is defined as a function mapping: PMV=f(M, t_ob, t_a, RH, and t_r), where M is a human metabolic rate. The PMV value is obtained using an existing PMV evaluation model and is used to assess a thermal comfort level of occupants.

According to one or more embodiments, in the step 2, the minimum required fresh air volume Q based on the number N of occupants for indoor occupants is calculated using the following formula:

Q = q × N ,

• • where q is a minimum fresh air volume per person; in some example, according to the requirements specified in GB 50736-2012: Design Code for Heating, Ventilation and Air Conditioning of Civil Buildings, q may be set as follows: 30 m³/(h·person) for offices, 11-14 m³/(h·person) for meeting rooms, and 22-28 m³/(h·person) for classrooms.

As shown in FIG. 3 and FIG. 4, an anti-condensation radiant cooling system is presented, comprising an anti-condensation radiant cooling device 100, an indoor status parameter monitoring device, and a control system. In some embodiments, the anti-condensation radiant cooling device 100 comprises an anti-condensation radiant cooling device 101 and a dedicated outdoor air system 102; the anti-condensation radiant cooling device 101 comprises a radiant cooling panel 1011 and an infrared-transparent material layer 1012; a side of the infrared-transparent material layer 1012 opposite to the radiant cooling panel 1011 serves as an air contact surface, and a sealed interlayer 1013 is provided between the air contact surface of the infrared-transparent material layer 1012 and the radiant cooling panel 1011, so as to isolate the radiant cooling panel 1011 from an ambient air; the sealed interlayer 1013 has an interior filled with a vacuum or a dry gas.

In some embodiments, the indoor status parameter monitoring device comprises a thermal camera 201 and a temperature-humidity sensor; the thermal camera 201 is configured to acquire real-time temperature matrix data of indoor thermal images, and the temperature-humidity sensor is configured to acquire an indoor air temperature t_a and a relative humidity (RH) in real-time.

In some embodiments, the detection area of the thermal camera 201 covers the inner surface of exterior walls, the surfaces of interior walls, the floor, the ceiling surface, occupant entry/exit locations, and occupant activity areas. For example, one thermal camera 201 is installed on a wall surface facing an interior wall at a height of 1.5-1.8 m and oriented in a downward-facing view; another thermal camera 201 is installed on a wall surface facing the inner surface of an exterior wall, avoiding the occupant activity area, at a height of 0.8-1.2 m and oriented in an upward-facing view. The thermal camera 201 acquires real-time temperature matrix data of indoor thermal images in the form of an L×H pixel temperature matrix. FIG. 5 illustrates an image captured by a 307,200-pixel (640×480) thermal camera 201, FIG. 6 illustrates the L×H pixel temperature matrix of the image temperature data acquired by the thermal camera 201. In some examples, the temperature-humidity sensor is arranged at the indoor exhaust vent.

According to one or more embodiments, the control system is configured to perform the steps of the control method, and the control system comprises a computation processing module and an execution module. The computation processing module comprises a preprocessing unit, a temperature statistics unit, an occupant counting unit, a PMV calculation model, and a comprehensive heat transfer model.

In some embodiments, the preprocessing unit is configured to acquire the temperature matrix data of indoor thermal images and preprocess the data by setting a reference temperature range for a human body surface temperature and performing an element-by-element evaluation on a pixel temperature matrix of the temperature matrix data of indoor thermal images corresponding to a human activity area, such that when a matrix element has a temperature value within the reference range for the human body surface temperature, the matrix element is grouped into a human body surface temperature dataset Temp.Data_object;

In some embodiments, the occupant counting unit is configured to perform an occupant counting based on the temperature matrix data of indoor thermal images to obtain a number N of indoor occupants, and to calculate a minimum required fresh air volume Q for indoor occupants based on the number N of indoor occupants.

In some embodiments, the temperature statistics unit is configured to calculate an average value of matrix elements in the human body surface temperature dataset Temp. Data_object and store the average value as a human body surface temperature t_ob.

In some embodiments, the PMV calculation model is configured to calculate a PMV value under current indoor conditions based on the temperature matrix data of indoor thermal images, the indoor air temperature t_a, and the relative humidity (RH).

In some embodiments, the comprehensive heat transfer model is configured to calculate an air contact surface temperature t_m of the infrared-transparent material layer based on the temperature matrix data of indoor thermal images and the number N of indoor occupants, and to obtain the indoor air temperature t_a and the relative humidity (RH), and to calculate a real-time indoor dew point temperature t_d based on the indoor air temperature t_a and the relative humidity (RH).

In some embodiments, the execution module is configured to, after the anti-condensation radiant cooling device 101 is turned on, perform the following comfort-oriented control steps based on parameters processed by the computation processing module:

• • determining a condensation risk by determining whether the air contact surface temperature t_m is greater than a real-time indoor dew point threshold, the threshold being defined as the real-time dew point temperature t_a plus a margin value σ; the margin value σ may be set according to actual needs. In some examples, according to the requirements of JGJ142-2012, a supply water temperature of a radiant cooling system shall ensure that a surface temperature for cooling is 1-2° C. higher than the indoor air dew point temperature; therefore, the value of σ ranges from 1 to 2, and, for example, σ is set to 1;
    • if the air contact surface temperature t_m is not greater than the real-time indoor dew point threshold, the execution module is configured to control the DOAS 102 to operate at a highest airflow level, and to trigger a next round of control steps based on parameters calculated and processed in real time by the computation processing module;
    • if the air contact surface temperature t_m is greater than the real-time indoor dew point threshold, the execution module is configured to determine whether the indoor environment falls within a thermal comfort range, i.e., to determine whether the PMV value is greater than a first threshold value:
      • if the PMV value is greater than the first threshold, the execution module is configured to calculate a proportion of matrix elements in the human body surface temperature dataset Temp.Data_object whose temperature values are greater than the human body surface temperature t_ob, and determine whether the proportion is greater than a second threshold, and, for example, the second threshold may be set to 50%:
      • if the proportion is less than or equal to the second threshold, the execution module is configured to control the DOAS 102 to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, while increasing a cooling output of the radiant cooling panel 1011, to end a current control action process, and to trigger a next round of control steps based on parameters calculated and processed in real time by the computation processing module;
      • if the proportion is greater than the second threshold, the execution module is configured to control the DOAS 102 to operate at a highest airflow level, to end the current control action process, and to trigger a next round of control steps based on parameters calculated and processed in real time by the computation processing module;
    • if the PMV value is less than or equal to the first threshold, the execution module is configured to control the DOAS 102 to adjust an airflow to a level corresponding to the minimum required fresh air volume Q, and to further determine whether the PMV value is less than a third threshold, and, for example, the third threshold may be set to −1:
      • if the PMV value is less than the third threshold, the execution module is configured to reduce a cooling output of the radiant cooling panel 1011, and to trigger a next round of control steps based on parameters calculated and processed in real time by the computation processing module;
      • if the PMV value is greater than or equal to the third threshold, the execution module is configured to trigger a next round of control steps based on parameters calculated and processed in real time by the computation processing module.

According to one or more embodiments, the thermal camera 201 is configured to transmit the acquired temperature matrix data of indoor thermal images to the computation processing module, and the temperature-humidity sensor is configured to transmit the real-time indoor air temperature t_a and the relative humidity (RH) to the computation processing module.

According to one or more embodiments, the preprocessing unit is further configured to:

• • set a reference temperature range for a surface of the radiant cooling panel, a reference temperature range for an inner surface of exterior walls, and a reference temperature range for interior walls and other surfaces; and
  • perform an element-by-element evaluation on a pixel temperature matrix of temperature matrix data of indoor thermal images outside of the occupant activity area, wherein when a matrix element has a temperature value within the reference temperature range for the inner surface of the exterior wall, the matrix element is grouped into an exterior wall inner surface temperature dataset Temp.Data_ex. wall, when a matrix element has a temperature value within the reference temperature range for interior walls and other surfaces, the matrix element is grouped into an interior wall and other surface temperature dataset Temp.Data_in. wall, and when a matrix element has a temperature value within the reference range for the surface of the radiant cooling panel, the matrix element is grouped into a radiant cooling panel surface temperature dataset Temp.Data_cooling.

According to one or more embodiments, the occupant counting unit is configured to:

• • set a counting line at a coordinate position corresponding to a door position in the temperature matrix data of indoor thermal images corresponding to areas covering an entry/exit pathway of a room based on the human body surface temperature dataset Temp.Data_object;
  • define two opposite vectors perpendicular to the counting line to represent counting directions for exiting and entering occupants, respectively;
  • extract the human body surface temperature dataset and a corresponding coordinate set over consecutive frames; and
  • compare an offset of the coordinate set with respect to preset vector directions of the two opposite vectors to determine and record an exiting behavior and an entering behavior of a person represented by one of the two opposite vectors, and cumulatively counting the exiting behavior and the entering behavior to obtain the number N of indoor occupants, which is then transmitted to the temperature statistics unit.

According to one or more embodiments, the temperature statistics unit is further configured to perform statistical calculations on the received temperature datasets from various regions, including:

• • calculating an average value of matrix elements in the radiant cooling panel surface temperature dataset Temp.Data_cooling and storing the average value as a radiant cooling panel surface temperature t_{r_c};
  • calculating an average value of matrix elements in the exterior wall inner surface temperature dataset Temp.Data_ex. wall and storing the average value as t_{r_out},
  • calculating an average value of matrix elements in the interior wall and other surface temperature dataset Temp.Data_in. wall and storing the average value as t_{r_in}.

According to one or more embodiments, the temperature statistics unit is further configured to calculate an average radiant temperature t_r of an indoor environment, and an equivalent average radiant temperature t_{r_h} of non-cooled surfaces when occupants are present; the calculated average radiant temperature t_r of an indoor environment and a human body surface temperature t_ob are transmitted to the PMV calculation model; the PMV calculation model is configured to calculate a PMV value under current indoor conditions based on the average radiant temperature t_r, the human body surface temperature fob, the indoor air temperature t_a, and the relative humidity (RH).

The equivalent average radiant temperature t_{r_h} of non-cooled surfaces and the radiant cooling panel surface temperature t_{r_c} calculated by the temperature statistics unit are transmitted to the comprehensive heat transfer model. The comprehensive heat transfer model calculates the air contact surface temperature t_m through effective radiation analysis of each surface within the space using a radiative heat transfer network diagram, and is used to determine whether a condensation risk exists.

According to one or more embodiments, the anti-condensation radiant cooling system comprises a human-machine interaction panel 300 arranged indoors. Indoor occupants may use the human-machine interaction panel 300 to view data regarding the indoor air temperature t_a and the relative humidity (RH), and to manually adjust a fresh air volume of the DOAS 102 and a cooling output of the radiant cooling panel 1011 according to actual occupant needs.

According to one or more embodiments, the infrared-transparent material layer 1012 is arranged on a side of the radiant cooling panel 1011 facing the air. A sealed interlayer 1013 is provided between the infrared-transparent material layer 1012 and the radiant cooling panel 1011, such that the radiant cooling panel 1011 is isolated from an ambient air. The sealed interlayer 1013 having an interior that is filled with a vacuum or a dry gas, thereby allowing a radiative heat transfer on a surface of the radiant cooling panel 1011 to be independent from a convective heat transfer at the air contact surface of the infrared-transparent material layer 1012. The infrared-transparent material layer 1012 has high infrared transmittance, and may, for example, be made of polyethylene film, polypropylene film, or germanium glass. By using the infrared-transparent material layer 1012 to isolate the radiant cooling panel 1011 from the ambient air, the radiant cooling panel 1011 can operate at a cooling temperature below an ambient dew point without causing condensation. Consequently, the cooling performance of the radiant cooling panel 1011 is no longer constrained by the ambient dew point temperature, thereby effectively enhancing the cooling capacity per unit area of the radiant cooling terminal.

According to one or more embodiments, the anti-condensation radiant cooling device 100 comprises a cooling source device 103. The DOAS 102 comprises a fresh air unit 1021, a fresh air duct 1022, and an exhaust duct 1023. An air outlet of the fresh air unit 1021 is connected to an air inlet of the fresh air duct 1022, and an air outlet of the fresh air duct 1022 is connected to an indoor air supply vent. The fresh air duct 1022 is provided with a fresh air valve (FAV). An end of the exhaust duct 1023 is connected to an indoor exhaust vent, and the other end is connected to the outdoor environment. The exhaust duct 1023 is provided with an exhaust valve. In some examples, the fresh air valve is a multi-level adjustable valve, and the number of levels may be set according to a room size and its function. When it is necessary to adjust a fresh air volume of the DOAS 102 to a highest level, the fresh air valve may be adjusted to its highest setting. When it is necessary to adjust the fresh air volume to a level corresponding to the minimum required fresh air volume Q for the occupants, the fresh air valve may be adjusted accordingly to that level. In addition, the fresh air valve and the exhaust valve are configured with a linkage function, i.e., the exhaust air volume is controlled in coordination with the fresh air volume to meet the fresh air demand indoors while maintaining a slightly positive indoor pressure, thus ensuring sufficient air exchange and indoor air circulation.

In some embodiments, the cooling source device 103 comprises a chilled water unit 1031, a main water supply pipe 1032, a first water supply branch pipe 1033, and a second water supply branch pipe 1034. A water outlet of the chilled water unit 1031 is connected to a water inlet of the main water supply pipe 1032. Water inlets of the first water supply branch pipe 1033 and the second water supply branch pipe 1034 are respectively connected to a water outlet of the main water supply pipe 1032. A water outlet of the first water supply branch pipe 1033 is connected to a water inlet of the radiant cooling panel 1011, and the first water supply branch pipe 1033 is provided with a first regulating valve 10331. A water outlet of the second water supply branch pipe 1034 is connected to a water inlet of the fresh air unit 1021, and the second water supply branch pipe 1034 is provided with a second regulating valve 10341. By providing the first water supply branch pipe 1033 and the second water supply branch pipe 1034, the flow rate of chilled water delivered to the radiant cooling panel 1011 and the fresh air unit 1021 can be controlled. When it is necessary to increase a cooling output of the radiant cooling panel 1011, an opening degree of the first regulating valve 10331 may be increased (or opening adjustment (OA)), thereby increasing a water flow rate through the radiant cooling panel 1011 (the interior of the radiant cooling panel 1011 is provided with water pipes, and chilled water flows through the water pipes to transfer cooling capacity). The greater the water flow rate, the greater the volume of water passing through the radiant cooling panel 1011 per unit time, thereby increasing the cooling output. When it is necessary to reduce a cooling output of the radiant cooling panel 1011, an opening degree of the first regulating valve 10331 may be decreased, thereby reducing a water flow rate through the radiant cooling panel 1011 and consequently reducing its cooling output.

In addition, conventional radiant cooling terminals typically use high-temperature chilled water to prevent condensation, while fresh air units require low-temperature chilled water for dehumidification. This usually necessitates two separate chilled water units to meet the temperature requirements of the two systems, thereby increasing system complexity and cost. According to various embodiments, by using the infrared-transparent material layer 1012, the radiative heat transfer at the surface of the radiant cooling panel 1011 is made independent of the convective heat transfer at the air contact surface of the infrared-transparent material layer 1012. As a result, the cooling output of the radiant cooling panel 1011 is no longer constrained by the ambient dew point temperature. This allows the radiant cooling terminal and the DOAS to share chilled water of the same temperature, i.e., the anti-condensation radiant cooling device 101 and the DOAS 102 can operate using the same chilled water unit 1031. This simplifies the system, reduces equipment cost, and enhances the cooling capacity per unit area of the radiant cooling panel 1011 while ensuring that there is no risk of condensation.

According to one or more embodiments, a third regulating valve 10321 and a circulation water pump 10322 are sequentially arranged along a flow direction of the main water supply pipe 1032. Water-returning outlets of the radiant cooling panel 1011 and the fresh air unit 1021 are respectively connected to water inlets of a water-returning pipeline 1035, and the water outlet of the water-returning pipeline 1035 is connected to the return water inlet of the chilled water unit 1031. By providing the third regulating valve 10321, the water output from the main water supply pipe 1032 can be adjusted. By providing the circulation water pump 10322, water returning from the circuit of the radiant cooling panel 1011 and water returning from the circuit of the fresh air unit 1021 can be pumped back into the chilled water unit 1031 for cooling treatment. The resulting chilled water is then discharged again through the main water supply pipe 1032, thereby achieving recycling and reuse of water resources.

It should be noted that various embodiments of the present disclosure allow for modifications and refinements to be made by those skilled in the art without departing from the principles of the present disclosure. Such modifications and refinements should also be regarded as falling within the scope of the present disclosure.