Dynamics of aircraft cabin ventilation studied by in-flight infrared thermography

Abstract

Aircraft Cabin Displacement Ventilation (CDV) was investigated during flight tests in an A320 aircraft cabin with an automatically rotatable infrared camera. For this purpose a programmable, step motor driven infrared camera setup was developed, allowing for time resolved acquisition of the temperatures on the interior cabin surfaces during the flights. Static measurements reveal a characteristic, yet homogeneous temperature distribution in the cabin for both scenarios, pinpointing to a homogeneous cooling of the heat loads in the whole cabin. Analysis of time resolved measurements discloses that the cooling performance of the cabin is limited by thermal diffusion of heat inside of the interior cabin materials. Switching from pure CDV to a hybrid scenario, where 30% of the air flow rate is provided by the pre-existing lateral air outlets, allows to increase the initial surface cooling rates up to a factor of 2.