The air leakage rate

thermal comfort index

and temperature homogeneity indicators are used to evaluate the criteria of the key design parameters and the matching of the design and ambient parameters of the air curtain for the hot-air curtain used in winter. The evaluation uses a railway depot in northwestern China as an example. When the air supply velocity increases from 5.4 m/s to 9.3 m/s

the air leakage rate increases by 71.8%. A discharging angle of 10°–20° helps in reducing the leakage rate by 24.9% compared to the 0° discharge angle. While the temperature of the air supply does not affect the air leakage rate

it has a significant impact on the thermal comfort inside the plant. Furthermore

the ambient air direction and temperature have a trivial contribution to thermal comfort and the air leakage rate. Most importantly

the air leakage rate increases by 40% when the ambient velocity is > 2.6 m/s; therefore

measures other than the air curtain should be deployed to reduce air leakage in these regions.