دانلود رایگان مقاله انگلیسی یک سیستم تهویه جایگزین نوآورانه برای کابین های هواپیمایی - الزویر 2018

Abstract

In airliner cabins, mixing ventilation systems with gaspers are not efficient in controlling contaminant transport. To improve the cabin environment, this investigation proposed an innovative ventilation system that would reduce contaminant transport and maintain thermal comfort. We manufactured and installed the proposed ventilation system in an occupied seven-row, single-aisle aircraft cabin mockup. Air velocity, air temperature, and contaminant distribution in the cabin mockup were obtained by experimental measurements. The investigation used the experimental data to validate the results of CFD simulation. The validated CFD program was then used to study the impact of the locations and number of exhausts on contaminant removal and thermal comfort in a one-row section of a fully occupied Boeing-737 cabin. Although the diffusers in the proposed system were close to the passengers’ legs, the air velocity magnitude was acceptable in the lower part of the cabin and the leg area. The proposed system provided an acceptable thermal environment in the cabin, although passengers could feel cold when placing their legs directly in front of the diffusers. The four-exhaust configuration of the new ventilation system was the best, and it decreased the average exposure in the cabin by 57% and 53%, respectively, when compared with the mixing and displacement ventilation systems.

5. Conclusions This investigation proposed a new ventilation system to reduce contaminant transport and maintain thermal comfort in airliner cabins. The following are the major conclusions drawn from the study:

• The proposed ventilation system was manufactured and then installed in a fully occupied seven-row, single-aisle airliner cabin mockup. The air velocity, air temperature, and contaminant distributions in the mockup were measured. It demonstrated good contaminant removal potential and acceptable thermal comfort. Despite the fact that the diffusers in the proposed system were close to the passengers’ legs, the air velocity magnitude was small in the leg area and therefore would not create a draft. However, if a passenger placed his/her legs directly in front of the diffuser, he/she might feel cold.

• This study also conducted CFD simulation of the air distributions in the mockup, and the experimental data was used to validate the CFD results. The accuracy of the CFD simulation was acceptable for designing the cabin airflow.

• The study found the exhaust location to be a crucial design parameter for contaminant removal in airliner cabins with the proposed system. The validated CFD program was used to evaluate the location and number of exhausts in a one-row section of a fully occupied Boeing 737 cabin. The system configuration with four exhausts seemed to be the best choice, as it decreased the average exposure in the cabin by 57% and 53%, respectively, when compared with the mixing and displacement ventilation systems. The four-exhaust system also increased contaminant removal in the cabin by 2.6 times and 0.4 times, respectively, when compared with mixing and displacement ventilation systems. The PMVc with the proposed system was lower than that with the mixing ventilation system, but higher than that with the displacement ventilation system.