## 3 Results
### Daytime Thermal Environments
#### 3.2.3 Attached Sunspace's Thermal Environment  
The temperature distribution of the air interlayer is uneven in the attached sunspace due to the large cavity, especially during the process of the solar radiation rising. When the interior active window is opened, the convective heat exchange effect is affected by the distribution of air temperature inside the attached sunspace. Thus, the change of temperature distribution in the attached sunspace was measured after being exposed to the solar radiation. Figure 11 depicts the thermal environment distribution variation with time of the four longitudinal measuring points at the center of the attached sunspace. As shown in Figure 11a, in order to examine the morning thermal environment longitudinal distribution in the attached sunspace, we investigated the part 0.63 m south of the public wall, which is the longitudinal section where the previously established temperature measurement stations are located. As described in Figure 11b-f, the temperature in the attached sunspace steadily rises from 8:00, and the temperature stratifies from 8:30. Significant temperature stratification occurs at 9:00. The greatest temperature is recorded at point 2, which is 9.71 \({}^{\circ}\)C. The temperature of point 1 is lower than that of point 2, which is 7.22 \({}^{\circ}\)C, which is because of the closer to the glass roof, the more severe of heat loss. The temperature of lower point 3 and point 4 is 6.92 \({}^{\circ}\)C and 4.49 \({}^{\circ}\)C, respectively. The heat gain of the attached sunspace increases significantly after 9:30, but the temperature stratification structure is similar to 9:00. At 10:00, the longitudinal average temperature reaches 20.7 \({}^{\circ}\)C, while the temperature at point 2 in the upper middle is the greatest and the lower temperatures are top point 1, lower middle point 3 and bottom point 4 in this order. Figure 12 depicts the thermal environment distribution variation with time of the five transverse measuring sites at the top of the attached sunspace. As showed in Figure 12a, in order to examine the morning thermal environment cross distribution in the attached sunspace, is balanced in the longitudinal distribution due to the top position, a triangular cross section 0.1 m from the roof of the sunspace was investigated, where the previously established temperature measurement stations are located. As described in Figure 12b-f, the air temperature in the attached sunspace's top horizontal plane is essentially the same at 8:00, with the western portion being somewhat higher than the rest. The temperature difference is not evident due to the weak solar radiation. Solar radiation has increased from 8:30, and the temperature in each region starts to climb. Because the solar radiation angle is southeast to northwest, the southern portion of the attached sunspace gains total solar radiation sooner and more than the other locations, resulting in a much higher temperature than the other locations. Due to the western portion being close to the wall, the resulting solar radiation was absorbed by the wall, and the temperature was lower than that in the south area but higher than that in other locations. The east wall blocks solar radiation, and the eastern portion was exposed to solar radiation last, and the temperature can only rely on the air movement inside the sunspace to increase. Therefore, it is always the lowest temperature in the attached sunspace. At 9:30, the temperature remained higher in the southern portion than in the central portion than in the northern portion than in the eastern portion. In summary, according to our research on the thermal environment of the attached sunspace during the heat collection process, the temperature field is unevenly distributed, and the internal heated air of the attached sunspace is more likely to gather in the upper middle position of the longitudinal distribution and the west and south position of the cross distribution in the morning.