New York: With schools set to open in many places, researchers at the Massachusetts Institute (MIT) show that good opening and heating systems, ventilation, and AC (HVAC) can help keep the classrooms safely as long as Covid-19 Pandemics.
The study also shows how certain class configurations can affect air quality and require additional steps, beyond the use of HVAC or open windows, to reduce the spread of aerosols – potentially covid small particles that can remain suspended in the air for hours.
Safe! You have managed to throw your votelogin to see the results “There is a set of conditions where we find clearly a problem, and when you see aerosol concentrations predicted around other people in the room, in some cases it is much higher than.
What will be said Model (standard), “said Leon Glicksman, a MIT architecture and professor of Engineering.
For this study, it appeared online in the journal and environmental buildings, the researchers used the dynamics of computing fluid – a sophisticated airflow simulation – to check 14 different class ventilation scenarios, nine involving the HVAC and five systems involving windows.
The research team also compares their modeling for the past experimental results.
One of the ideal scenarios involves fresh air into the class near the ground and moves firmly higher until it exits the room through the ventilation of the ceiling.
This process is assisted by the fact that hot air rises, and the warmth of the body of people naturally produces up “hot feathers,” which carries air towards ceiling ventilation, at a rate of around 0.15 meters per second.
Given ventilation ceiling, then, the aim is to create vertical air movements up to air from the room, while limiting horizontal air movements, which spread aerosols among students sitting.
This is why wearing a mask in the room makes sense, said Glicksman.
The mask limits the horizontal speed of the aerosol which is exhaled, keeping the particles near the hot plum so that the aerosol rises vertically, as observed by researchers in their simulation.
Normal vegetable creates aerosol speed of 1 meter per second, and coughs create a higher speed – but the mask keeps the speed low.
However, with the use of Windows and HVAC closed, the problem of air flow appears in the simulation classroom in the winter, with a cold window on the side.
In this case, because the cold air near the window naturally sinks, it interferes with the upcoming class air flow overall, even though there is human heat.
In this scenario, someone infected with Covid-19 sitting near the window will be very likely to spread their aerosols.
But there is an improvement for this problem: Among other things, placing heaters near the cold window limiting the impact on the class air flow, Glicksman said.
How to save fresh class air during covid
