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ABSTRACT Lightweight and thermal insulative foam concrete has gathered increasing interests in buildings for energy efficiency. However, their density (~400 kg/[m.sup.3]) and thermal conductivity (0.10 W/(m*K)) need to be further [...]

•Thermal comfort of pedestrians while wearing masks in semi-open spaces was evaluated.•Wearing masks affected the breathing and thermal sensation of the subjects.•Thermal sensation with masks was higher than that without masks by nearly 0.3 units.•Subjects with masks require low temperatures to achieve a thermoneutral state.

•Wearing masks for more than 2 h, more than half subjects feel uncomfortable.•The mask has no obvious influence on the whole body.•Wearing a mask for a long time has significant impact on head and chest comfort.•In winter the differences of the neutral Topbetween wearing masks and without masks were no significant.

AbstractA full size simulation laboratory aircraft cabin comprising three rows of seats has been built. This represents the Airbus A320 and the China C919 aircraft. Experimental research on the attenuation rule of the individual air-conditioning isothermal jet flow from nozzles positioned above the seats was conducted. The results show that axial air velocity continuously decreases with increasing cross-sectional distance. For a distance x< 0.4 m, (the axis air velocity sharp attenuation area), the velocity of attenuation slows. When 0.7 m x< 0.9 m, the velocity remains at about 1m.s-1with the vents fully open, and at about 0.5 m.s-1with the vents half open. The air velocity distribution of different cross-sections is axisymmetric and basically in line with the circular outlet jet flow rule. Combined with empirical formulae, the turbulent coefficient values of the isothermal jet flow in the airplane cabin was established as 0.1021 with the vents fully open and 0.1776 with the vents half open. The spread angles αof jet flow for these two conditions were found to be 19.14° and 31.12° respectively. The axial velocity attenuation rule was also confirmed. The experimental results align with those anticipated by calculation.

In this investigation, the measurement thermal parameters and thermal comfort field survey were carried in six air conditioned hospitals in Guangzhou. A total of 114 valid questionnaires were collected. Based on the data, there were strong linear regression relationships between PMV and MTSV and operative temperature. The neutral PMV of medical staff was 0.004. The neutral operation temperature was 22.99 degC from the PMV model. The thermal comfort temperature which meets a satisfaction degree of 90% ranges from 21.29degC to 24.70degC. In addition, the neutral temperature was 24.36 degC from the linear regression of MTSV. The range of thermal comfort temperature was between 22.86degC and 25.85degC. Comparing the MTSV and PMV, the MTSV was lower than that of PMV.