Simulation Of Thermal Comfort In The Aircraft Cabin

In modern world, an increasing number of people will choose aircraft as a priority when traveling around, and the flying public will be more sensitive to the cabin environment, which is a special space with high density of population and particular physical conditions. The state out of the aircraft cabin at cruising altitude is the stratosphere with low pressure and temperature, so an aircraft environmental control system is necessary to maintain constant temperature,humidity and pressure inside the cabin to meet the requirements of the human body. While the interior of cabin is not so satisfying because passengers will encounter many uneasy factors such as high ozone levels, low air pressure, low humidity, shock and vibrations. In order to maintain comfort, effort must be made to analyze the thermal comfort conditions in the cabin. At present, the research of thermal comfort of the cabin environment is still on the way. Because the thermal comfort of the ground buildings is fully developed, this paper decided to study the cabin comfort with the indicators developed in ground buildings.This paper reviews the development of aircraft cabin environmental control system (ECS). Combined with the development of China's large aircraft project, the impact of cabin environment on the human body and related work was introduced. In order to optimize the application of ECS, the PMV-PPD index was adopted to investigate the thermal comfort of the aircraft cabin. With CFD software, a typical simulation for Boeing767 cabin with traditional form of air supplying method was analyzed, and the thermal comfort was discussed. Gambit was adopted to build the physical model of the cabin, and unstructured grid was chosen to mesh the model. The simulation was validated by the data collected in a laboratory at Purdue University. In the simulation, the RANS model and LES model were verified to prove their feasibility in cabin airflow simulation. Fluent was used to calculate the air distribution inside the cabin. The temperature and air velocity distribution on the plane of human head and foot was analyzed. And the PMV-PPD was calculated by MATLAB. Comparison of PMV-PPD and the distribution of air velocity and temperature proved that PMV index can reflect the state of comfort inside the cabin at a certain level, but failed to demonstrate the local airflow pattern around the human body. Due to the complexity of the internal structure of the cabin, there will be areas of local turbulence which affects human comfort. The application of a new air supply system in the cabin needs further study.