A good way to cool a sweltering urban canyon? Put a lid on it.

Written by
John Sullivan
John Sullivan, School of Engineering and Applied Science
April 18, 2024

Researchers at Princeton’s engineering school found that placing a specially designed lid over a box can dramatically increase the airflow from wind blowing across the upper surface. It is not just a parlor trick. The information could help clean and cool urban canyons in cities like New York and Hong Kong and improve ventilation in popup restaurants and bus shelters.

“If you cut the lid in a certain pattern and stretch it, it becomes three-dimensional,” said Elie Bou-Zeid, a professor of civil and environmental engineering at Princeton and one of the lead researchers. “It can guide the flow of air to come in and out in ways that are better for ventilation than having no lid whatsoever.”

The researchers found that a cover with a row of evenly spaced, tilting slats, called louvers, can increase the airflow in a box by channeling wind that ordinarily would flow over the open top. The researchers further modified the top’s geometry using the Japanese art form kirigami. This technique allowed the researchers to stretch and bend the cover in novel ways, which further increased the amount of air moving through the enclosure.

The paper was published Feb. 4 in the Journal of Wind Engineering and Industrial Aerodynamics. 

Environment Tags
Research Themes