Experimental Study of Aerosol Dispersion in a Long-Range Aircraft Cabin Mock-Up

Abstract

Novel ventilation systems for aircraft cabins have attracted the attention of scientists and aircraft manufacturers during the last years due to their potential of energy saving as well as a higher level of thermal comfort. Since the coronavirus pandemic, the spread of aerosols in cabins has become another important criterion. To allow for a greener and smarter testing of novel ventilation concepts for future long-range airliners, a full-scale twin aisle cabin mock-up with thermodynamically realistic boundary conditions by means of temperature-controlled fuselage elements was developed at the German Aerospace Center (DLR) in Göttingen, for details see Lange et. al [1]. The new research facility allows to investigate different, well-defined ventilation concepts under varying thermodynamic boundary conditions, thus reducing cost- and resource-expensive flight testing [3]. New ventilation technology bricks can be tested in this ground-based, greener aviation research facility. To determine optimal comfort parameters for the passengers, a jacket cooling system was used to investigate the ventilation systems with the thermodynamically realistic boundary conditions Cruise and Hot Day on Ground characterized by cold and warm temperature boundary conditions, respectively. Temperature-controlled thermal manikins (TMs) allow for the simulation of heat dissipation and obstruction of real passengers, see Figure 1. Figure 1: Interior of cabin mock-up with thermal manikins [2] In addition to the existing measuring system, 100 aerosol sensors were attached to the heads of the TMs for this study in order to investigate the propagation from different seats, see Figure 2. Similar studies were already performed in a single-aisle aircraft cabin [4] revealing, that the increased aerosol particle concentrations were only found in a confined area around the source. Further, they confirmed that there is a week impact of the source seat location on the local spreading of aerosol particles. Figure 2: Aerosol-exhaling thermal manikin and aerosol sensor at the head of the TM The dispersion of aerosols originating from one source, the index passenger, within the cabin of a generic long-rang aircraft cabin was studied experimentally using an aerosol-exhaling thermal manikin, see Figure 2. The overall aim of the present study is to enhance the knowledge on the influence of the passenger cabin ventilation concept on the aerosol particle spreading. Therefore, we determine experimentally the aerosol spreading for a generic mixing ventilation (MV), currently installed in almost all commercial aircraft, and for Cabin displacement ventilation (CDV). Both concepts were analyzed for various air flow rates and spreading locations to allow for a detailed analysis to enhance the fundamental knowledge on the aerosol dispersion determining parameter. [1] Lange, P. et al., 2022. Realistic flight conditions on ground new research facility for cabin ventilation. CEAS Aeronautic Journal, 13(3), pp. 719 - 738, doi: 10.1007/s13272-022-00594-2. [2] https://www.dlr.de/content/en/research-facilities/modular-cabin-mock-up-goettingen-mkg.html [3] https://www.dlr.de/as/en/desktopdefault.aspx/tabid-17350/27473_read-69992/ [4] Schmeling, D. et al., 2023. Numerical and experimental study of aerosol dispersion in the Do728 aircraft cabin. CEAS Aeronautic Journal, online-first, doi: 10.1007/s13272-023-00644-3.