A layer of cool, healthy air

Dec 17, 2012

Stratum ventilation systems have been touted as a much more energy efficient system for cooling buildings such as school rooms and offices in hotter climes based on the provisions of the recent ANSI/ASHRAE 55-2010. They may also reduce the risk of the spread of airborne diseases according to a study to be published early next year in the journal World Review of Science, Technology and Sustainable Development.

This approach to cooling small and medium-sized rooms in a building has come to the fore as a low-cost alternative to high-energy air-conditioning systems particularly in East Asia and is being recommended for school buildings and other establishments by several governments. In this system a horizontal is produced. However, Lin and colleagues hoped to address the potential problem with any air distribution system in understanding how it might disperse airborne viruses, such as flu viruses, present on expectorated sputum .

Zhang Lin, Jinliang Wang, Ting Yao, T.T. Chow and K.F. Fong of the City University of Hong Kong have created a to help them predict the movements of exhaled droplets in a room with different types of air distribution systems: mixing ventilation, displacement ventilation and stratum ventilation. The simulation is based on the so-called drift-flux model developed from an Eulerian-Eulerian approach is adopted to simulate the particle movement in a room.

"The results show that the created by different ventilation methods have great influence on the particle fates," the team explains. The for the breathing zone under stratum ventilation are significantly lower than that under mixing ventilation or with displacement ventilation. "This implies that the risk of pathogen inhalation under stratum ventilation is also lower," the team adds. The team's model demonstrates that of the various ventilation systems the occupants of stratum ventilated room would have the lowest risk of infection.

Explore further: Greater safety and security at Europe's train stations

More information: "Numerical comparison of dispersion of human exhaled droplets under different ventilation methods" in World Review of Science, Technology and Sust. Development, 2013, 10, 142-161.

add to favorites email to friend print save as pdf

Related Stories

New gas sensors for monitoring carbon dioxide sinks

May 08, 2008

A novel gas sensor system makes it possible to monitor large areas cost-effectively the first time. The patented gas sensor is based on the principle of diffusion, according to which certain gases pass through ...

Recommended for you

Greater safety and security at Europe's train stations

Sep 01, 2014

When a suspicious individual fleas on a bus or by train, then things usually get tough for the police. This is because the security systems of the various transportation companies and security services are ...

Fingerprints for freight items

Sep 01, 2014

Security is a top priority in air freight logistics but screening procedures can be very time consuming and costly. Fraunhofer researchers intend to boost efficiency with a new approach to digital logistics, ...

On the way to a safe and secure smart home

Sep 01, 2014

A growing number of household operations can be managed via the Internet. Today's "Smart Home" promises efficient building management. But often the systems are not secure and can only be retrofitted at great ...

DIY glove-based tutor indicates muscle-memory potential

Aug 31, 2014

A senior editor at IEEE Spectrum worked on a DIY project that enabled his 11-year-old son to improve his touch typing by use of a vibrating glove. His son was already "pretty quick on the keyboard," said ...

User comments : 0