**2. Numerical Development and Verification**

Computational fluid dynamics (CFD) has proved itself to be a powerful numerical tool in modeling the in-cabin environment. Figure 1 describes our analytical procedure based on the CFD approach. The solar calculator was imposed to compute the solar irradiation. The solar load model was used to calculate radiation effects from the sun's rays that enter the cabin domain. Turbulence and radiation models were applied to capture the airflow and temperature. The pollutant emission model linked the temperature and emission rate (ER) of the cabin interiors. Then, the data of hot-soak temperature, airflow distribution and pollutant concentration were obtained.

**Figure 1.** The framework of our methodology.
