**4.7 Temperature and ventilation: computational fluid dynamics**

The air quality and its impact on humans during the cruise are determined by the aeronautical comfort design and have strong influences on the thermal conditions of the passengers. The air recirculation used before the cause of airborne pathologies by various types of viruses. For example, according to researches presented during the Roomvent Congress, 2014, ventilation is related to the circulation of contaminants in airplanes cabins that from expiratory activities, cause cross-contamination events. Belonging to the list of studies about environmental

**Figure 22.** *Isometric view of passenger seated airspeed.*

#### **Figure 23.**

*Airspeed with a seated passenger (0.35–0.49 m/s).*

comfort this research therefore, evaluates the actual thermal behavior of the airplane commercial user. In the face of the need to investigate air diffusers, responsible for the crew discomfort and for the transmission of diseases such as the so-called SARS (Severe Acute Respiratory Syndrome), and the challenges that are imposed on the intentions to design a healthy and comfortable environment in the cabins, we analyze

**Figure 24.** *Air temperature with a seated passenger (23.4–27.4°C).*

**Figure 25.** *seated passenger airspeed (0–0.37 m/s).*

the air distribution in the interior project of such cabins. The research focuses on the armchair and duct shapes with the use of the Computational Fluid Dynamic (CFD) tool. The CFD simulation used the software Autodesk Geometry/Mesh/Solver/Post processing.

Through CFD simulations it was found that the air exits run from the top part to the bottom part of the plane.

**Figure 26.** *Seated passenger airspeed (0–0.89 m/s).*

**Figure 27.** *Seated passenger refinement mesh.*

**Figure 28.** *Mask usage during flight.*

**Figure 28** shows the effect of the air current circulation and dispersion of particles throughout the aircraft cabin. This demonstrates that it is important to use personalized ventilation during the covid-19 pandemic period. According to Anvisa [16], the airflow of the gasper must be directed straight between passengers to avoid that they inhale the air from one another, avoiding disease dissemination.
