Taken Xuanyun SW300PRO as the research plant, the influence of wake field on the safety of civil aviation aircraft during idling deicing is studied. A numerical model of idle wake flow is established, through which temperature and velocity distributions are analyzed, enabling demarcation of safe zones in the flow field. The Standard k-ε model is used to analyze the heat flow field of engine tail by comparing the numerical results of three typical turbulence models and the experimental data. Results indicate conical diffusion patterns of wake temperature and velocity radiating from the nozzle centerline, where flow divergence initiates at 0.6 m downstream. Thermal analysis reveals high-temperature zones (z<0.9 m, y<0.5 m) with 569-976 K, while low-temperature regions (z>2.5 m, y>0.6 m) maintain temperatures below 323 K. Hydrodynamic measurements show high-velocity cores (z<0.2 m, y<0.2 m) at 77-100 m/s, contrasting with low-speed areas (z>0.9 m, y>0.2 m) capped at <20 m/s. The human safety zone distance is: z>2.5 m, y>0.5 m. The research findings can provide valuable insights for accurately analyzing the thermal flow field of large civil aviation engine wake flows and for defining the safety zones for ground deicing operations during engine idle conditions.