numerical simulation of exhaled particle transmission in a car cabin with open windows

The present study investigated the transmission of exhaled particles generated by coughing inside a car cabin, considering eleven different window opening configurations. the results indicated that particle dispersion and removal were mainly affected by the airflow, which was largely determined by the window opening configurations. notably, efficient ventilation and a large number of open windows did not necessarily result in lower infection risk. given the complex structure and formation of intricate airflow patterns within the cabin, airborne particles could spread throughout the cabin and deposit on the interior walls. as particles tended to escape or deposit rapidly within the first 10 s, precautionary measures were necessary during this time frame following a passenger’s coughing activity. furthermore, closing the window adjacent to the driver effectively reduced the proportion of exhaled particles passing through the driver’s breathing zone due to the rear-in and front-out airflow pattern, thus mitigating the risk of infection.