Coronavirus: Using computer simulation to minimise cross-infection

At the height of the Covid-19 pandemic in Wuhan earlier this year, the Chinese government erected 16 makeshift hospitals in the city within weeks to handle the surge in the number of infected patients.

The use of prefabricated building materials had helped to speed up the construction process, but just as critical was the need to control the airflow within a hospital to prevent transmission of the highly contagious disease among patients and medical workers.

Already familiar with using computer simulation to design office buildings, China’s Central-South Architectural Design Institute (CSADI), the architects behind Wuhan’s biggest makeshift hospital, Leishenshan, turned to the same technology to validate the design of ventilation systems.

Tapping a simulation software called Simulia XFlow from Dassault Systèmes, a French supplier of industrial software, CSADI was able to assess the layout of each hospital room and model its airflow to contain the spread of the disease.

“We have to ensure there’s sufficient airflow in the hospital,” said Samson Khaou, executive vice-president for Asia-Pacific and managing director for Asia-Pacific South at Dassault Systèmes. “But on the other hand, you also have to make sure that with this air circulation, you know the exact impact to healthcare workers who are inside the room with patients.”

Khaou said for medical workers donning personal protective equipment, similar simulations were also performed to ascertain how far they should stay away from another person or patient in the same facility to minimise the risk of infection.

Unlike the use of prefabricated materials, which has paved the way for builders to construct buildings and other facilities at breakneck speeds, Khaou said using simulation software was less about achieving time savings. 

“It’s more about safety, and to make sure that we have considered all hygiene and prevention measures…and to validate and regulate airflow within a room,” he said.

Khaou said while similar airflow simulations can be conducted for existing medical facilities, it can be difficult to fine-tune or retrofit existing ventilation systems should the results be unfavourable. A more plausible use case, he added, could be to simulate the risks for healthcare workers as they enter a ward in an existing hospital, and the procedures they have to follow to guard against cross-infection.

These simulations can also be applied in manufacturing plants, which are expected to implement social distancing measures in a post-Covid-19 world.

“When we restart manufacturing, things will not be same as before,” said Khaou. “We have to think about whether we can automate existing facilities and increase social distancing on the factory floor. It also means we have to rethink the way we plan the workforce…and reconsider the shifts within manufacturing operations.”

Dassault’s collaboration with CSADI is part of its corporate social responsibility efforts to support local communities amid the Covid-19 outbreak. Khaou said the company does not plan to turn the initiative into a business.

“We did it as it’s important for a global company like us to offer the knowledge and technology that we have to support the community at this point in time,” he said, adding that the company has also worked with Inali, a non-profit organisation in India, to design smart ventilators for Covid-19 patients.

Developed in just eight days, the ventilators can monitor and adjust the air velocity and air pressure required for them to function properly. They can also identify the appropriate oxygen level for a patient and the safety metrics required for reliable and safe use.