The Effects of Inlet Airflow Angle on the Quality of Mixing Air Distribution in an Aircraft Cabin Mock-up

This paper presents a numerical investigation on the effects of inlet airflow angle on the airflow, temperature and CO2 concentration fields in a three-row airliner cabin. The computations are conducted using Ansys-Fluent and the numerical results were compared against published experimental data. The inlet airflow is supplied into the aircraft cabin at six different directions of A (0°, 180°), B (355°, 185°), C (350°, 190°), D (340°, 200°), E (330°, 210°) and F (315°, 225°). The numerical results showed that flow pattern, temperature distributions and CO2 levels are improved significantly inside the whole cabin and at passengers’ breathing zones in case of changing the inlet airflow angle. The performance of mixing-air distribution system for the whole aircraft cabin is enhanced remarkably in case of using small inlet angles. Angles B (5°) and C (10°) provided the best ventilation performance among the six tested angles within the whole cabin and at local breath zones of passengers in terms of thermal and health comfort. Moreover, inlet airflow angle C (10°) showed high constancy and stability in the pattern of the flow field and temperature and low CO2 level in cabin centre area compared to inlet airflow angle B (5°) for both the whole aircraft cabin and local breathing zones.