Effect of evergreen tree planting patterns on the winter microclimate and thermal comfort in residential areas: A study in Tai'an

Evergreen trees are widely used as landscape elements in residential developments within cold regions. However, limited research has been conducted on the effects of evergreen trees on winter microclimate and outdoor thermal comfort (OTC). This study investigates the impact of different planting patterns of evergreen trees, including regular row planting, lump concentration planting and natural group planting, on winter microclimates and OTC in urban residential areas. We developed a refined vegetation model in ANSYS Fluent by incorporating parameters such as tree resistance to airflow, turbulent kinetic energy, transpiration cooling, and shading effects. Measurements and simulations were conducted in a residential area within Tai'an, China. The results indicate that the regular row planting pattern could effectively enhance microclimate and OTC conditions in areas with low solar radiation and high wind speed (WS) by avoiding local wind tunnel effects. In contrast, the lump concentration or natural group planting patterns tend to produce pronounced wind tunnel effect in areas with higher WS and are more suitable for areas with lower WS. This study integrates numerical simulations with evergreen tree planting strategies to provide valuable insights for optimizing residential green space planning and enhancing OTC in winter. • Field measurements and computational fluid dynamics simulations were integrated. • A Fluent vegetation model was optimized, factoring resistance, cooling and shading. • The impact of evergreen tree patterns on winter microclimate was simulated. • This study proposes strategies for winter thermal comfort in China's cold zones.