Anti-condensation radiant cooling system and control method thereof

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 ta 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 ta, 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 tob;
• 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 tm 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 td based on the indoor air temperature ta 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 tm 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 td plus a margin value σ;
• if the air contact surface temperature tm is greater than the real-time indoor dew point threshold, proceeding to step 4;
• if the air contact surface temperature tm 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 ta, 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 tob, 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.