US2026063313A1PendingUtilityA1
Anti-condensation radiant cooling system and control method thereof
Est. expiryAug 30, 2044(~18.1 yrs left)· nominal 20-yr term from priority
F24F 11/64F24F 11/74F24F 5/0089F24F 2110/20F24F 2013/221F24F 2110/10F24F 2120/10F24F 11/63Y02B30/70F24F 11/89F24F 11/43
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Claims
Abstract
A control method for an anti-condensation radiant cooling system, including: step 1, acquiring temperature matrix data of indoor thermal images, an indoor air temperature ta, and a relative humidity (RH); step 2, performing an occupant counting for indoor active occupants; step 3, determining a condensation risk; 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 ta, and the relative humidity (RH).
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1 . A control method for an anti-condensation radiant cooling system, the anti-condensation radiant cooling system comprising an anti-condensation radiant cooling device and an indoor status parameter monitoring device,
wherein the anti-condensation radiant cooling device comprises an anti-condensation radiant cooling device and a dedicated outdoor air system, and the anti-condensation radiant cooling device comprises a radiant cooling panel and an infrared-transparent material layer, wherein 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; and wherein 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 t a and a relative humidity (RH) in real-time; and after the anti-condensation radiant cooling device is turned on, the control method comprising: step 1: acquiring temperature matrix data of indoor thermal images, an indoor air temperature t a , and a relative humidity (RH); and preprocessing the temperature matrix data of indoor thermal images comprising:
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 of matrix elements in the human body surface temperature 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 the 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 the 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 the 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.
2 . The control method according to claim 1 , wherein 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, when a third matrix element has a temperature value within the reference temperature range for the interior walls and other surfaces, the third matrix element is grouped into an interior wall and other surface temperature dataset, and 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 into a radiant cooling panel surface temperature dataset.
3 . The control method according to claim 2 , wherein the 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 the 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 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.
4 . The control method according to claim 2 , wherein 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.
5 . The control method according to claim 4 , wherein 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 comprises:
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 the interior walls and other surfaces, A out is an area of the 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 m 2 , 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 T r_c =t r_c +273.15; 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.
6 . The control method according to claim 5 , further comprising 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; 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.
7 . The control method according to claim 6 , wherein the real-time indoor dew point temperature t d 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).
8 . The control method according to claim 5 , wherein the step 4 further comprises calculating the 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); and
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.
9 . The control method according to claim 1 , wherein the minimum required fresh air volume Q based on the number N of indoor occupants is calculated using the following formula:
Q
=
q
×
N
,
where q is a minimum fresh air volume per person; q is taken as 30 m 3 /(h·person) for offices, 11-14 m 3 /(h·person) for meeting rooms, and 22-28 m 3 /(h·person) for classrooms.
10 . An anti-condensation radiant cooling system, comprising an anti-condensation radiant cooling device, an indoor status parameter monitoring device, and a control system,
wherein the anti-condensation radiant cooling device comprises an anti-condensation radiant cooling device and a dedicated outdoor air system, 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; wherein the indoor status parameter monitoring device comprises a thermal camera and a temperature-humidity sensor, the thermal camera configured to acquire real-time temperature matrix data of indoor thermal images, and the temperature-humidity sensor configured to acquire an indoor air temperature t a and a relative humidity (RH) in real-time; wherein the control system is configured to perform steps of the control method according to claim 1 , the control system comprising a computation processing module and an execution module:
the computation processing module comprising a preprocessing unit, a temperature statistics unit, an occupant counting unit, a PMV calculation model, and a comprehensive heat transfer model,
wherein 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;
wherein 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;
wherein 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 ;
wherein 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); and
wherein 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); and
the execution module 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 steps of the control method 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 steps of the control method 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 steps of the control method 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 steps of the control method 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 steps of the control method based on parameters calculated and processed in real time by the computation processing module.Cited by (0)
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