The airflow distribution characterised by different large- and small-scale eddies in the aircraft cabin is the most important factor to maintain passengers' thermal comfort and to remove contaminants. The airflow distributions in narrow-body aircraft cabins are based on the principle of mixing ventilation. Opposing jets from air diffusers can cause stream deflection and oscillation, which results in the asymmetry of large-scale instantaneous airflow structures. This dynamic airflow structure is very important for analysing time series parameters. Therefore, this study applied numerical simulation to examine the oscillation and asymmetry of instantaneous airflow field structures and phase space reconstruction and used spectrum analysis to evaluate the oscillation amplitude and period of dynamic airflow structure. We also studied the factors that influence the dynamic airflow structure, such as air supply speeds, air supply angles and the strength of the thermal plume. The results showed that as the air supply speed increased, the swing amplitude of the instantaneous airflow structure increased, while the period decreased. The air supply angle affected the jet attachment and collision angle, which in turn affected the swing amplitude and period. The thermal plume restrained the formation of large-scale swings and contributed to the appearance of small-scale structures.

In the field investigation of rural dwellings, it was found that thermal feelings are significantly different with varied envelopes even under the same indoor air temperature, and this paper explores the phenomenon in simulation. Based on building thermal investigations in several villages of North China, a typical energy and environment simulation model for rural residences was developed using DeST, and the hourly parameters of temperature and humidity were used to calculate the adaptive thermal comfort (APMV) of the rooms. The results show that the main reason for the different thermal comfort at the same air temperature is the large difference in the inner surface temperature. By adjusting the insulation thickness of the envelope structure, the relationship between it and the APMV value is obtained. By adjusting the insulation thickness of the enclosure structure and getting the correlation between it and the APMV value, it is obtained that when the heat transfer coefficient of the enclosure structure meets 0.5 W/(m²·K), the indoors can be in thermal comfort. This paper considers that the indoor air temperature cannot represent the APMV to evaluate the indoor thermal comfort, and the APMV value should be used to evaluate the thermal comfort of the renovated building and calculate the corresponding energy saving rate.