Thermal comfort evaluation of people in subway station

We analyzed the characteristics of subway station environment and the change of thermal comfort for passengers when they are in and out of the station. The dynamic thermal comfort evaluation model RWI(relative warmth index) and HDR(heat deficit rate) were built on the distinguishing features of public area in subway station. Taking one representative subway station in Nanjing as the research object, the thermal comfort conditions in different seasons and different parts were studied by field tests, questionnaires and model-evaluating. The calculated RWI shows that although the thermal comfort in Nanjing metro is relatively acceptable, ideal thermal comfort has not been achieved. And it is found that associated with predicted mean vote(PMV), using RWI can evaluate the thermal comfort more precisely.

Performance of the Multilayer Film for Infrared Stealth based on VO_(2) Thermochromism

With the development of detection and identification technology,infrared stealth is of great value to realize anti-reconnaissance detection of military targets.At present,infrared stealth materials generally have deficiency,such as complex structure,inconvenient radiation regulation and cumbersome preparation steps,which greatly limit the practical application of infrared stealth materials.In view of the above deficiency of infrared stealth materials,we proposed a kind of multilayer film for infrared stealth using VO2thermochromism based on the temperature response mechanism of tuna to adjust its color,and through the intelligent reversible radiation regulation mechanism to meet the infrared stealth requirements of tanks in different actual scenes.The results show that when the temperature increases from 300 K to 373 K,the peak emissivity of the film decreases from 94%to 20%in the 8-14μm band after structural optimization,which can realize the infrared stealth of the high temperature target in the 8-14μm band.The average emissivity of the multilayer film for infrared stealth at3-5μm and 8-14μm band can be reduced to 34%and 27%at 373 K,and the peak emissivity at 5-8μm band can reach 65%,realizing dual-band infrared stealth in the 3-5μm and 8-14μm bands and heat dissipation in the 5-8μm band.The multilayer film for infrared stealth based on VO2thermochromism designed by the authors can meet the characteristics of simple film structure,convenient radiation regulation and simple preparation.