Study of Unsteady Ventilation for Aircraft Cabins

Creating a safe and comfortable air environment for aircraft cabins is important for flight passengers inside. Currently steady ventilation is commonly used in environmental control systems of the commercial aircraft cabins, but the constant air-supply parameters often bring complaints about the unsatisfactory thermal comfort and air quality in cabins. To improve the air environments in aircraft cabins, this study explored unsteady ventilation for cabins by CFD. Three strategies for unsteady ventilation with different air-supply velocities were applied to a cabin model. The air velocities, air temperatures and mean ages of air near passengers were monitored and compared, in order to validate the proposed strategies for unsteady ventilation in aircraft cabins. The results showed that compared with the conventional steady ventilation as well as the unsteady ventilation with square and sinusoidal air-supply velocities, the unsteady ventilation that simulated the natural wind could produce varied and soft airflows without draft, although the mean age of air and air temperature near passengers were not significantly improved. Optimization of the air-supply velocities and temperatures for the simulated natural wind to both improve the thermal comfort and air quality in cabins requires further exploration.