Hoping to prevent future chemical attacks, such as the April 4, 2017 incident in Syria where 600 people were injured and more than 80 people were killed by sarin gas, University of Texas at San Antonio (UTSA) researchers set about developing a method for protecting people from such an attack.

A team of UTSA researchers led by mechanical engineering professor Kiran Bhaganagar created models capable of simulating toxic gas dispersals using only limited information.

"If there is a sudden a chemical attack, questions that are important are 'how far does it go' and 'what direction does it go,'" Bhaganagar said. "This is critical for evacuations."

Factors such as turbulence, atmospheric heating or cooling of the surface, wind gradient and chemical density will all impact plume dispersion, or the spread of chemicals in the air.

"In the nighttime and early morning, even when you have calm winds, the gradients are very sharp, which means chemicals travel faster," Bhaganagar explained.

Using those factors to make predictions about plume dispersions, researchers created and conducted computer simulations on the Stampede2 supercomputer located at the Texas Advanced Computing Center (TACC).

"In Syria, it was very bad because the timing caused it to be ideal conditions to spread very fast," Bhaganagar said. "We ran the actual case of Syria on the TACC supercomputer, got all of the background information and added it to the models, and our models captured the boundaries of the plume and which cities it spread to. We saw it was very similar to what was reported in the news. That gave us confidence that our system works and that we could use it as an evacuation tool."

The study appears in the journal Atmospheric Pollution Research.