Analysis of wind field and turbulence characteristics according to high-rise building distribution and surface radiation conditions using PALM

In urban environments, wind is a key meteorological factor that strongly affects the lives of urban residents, including the dispersion of air pollutants and heat as well as thermal comfort at pedestrian level. The distribution of building heights is a major determinant of the surrounding wind field patterns. Solar radiation is also known to exert a substantial influence on the wind field through surface heating and shadow induced thermal contrasts. Therefore, as a fundamental study for urban modeling aimed at predicting urban microclimates, this work quantitatively analyzes how building height variation and radiative heat transfer affect the urban wind environment. To simulate the urban wind environment, we use the PALM large eddy simulation model under idealized urban conditions to examine differences in the wind field around buildings associated with changes in the height distribution of high rise buildings. Under conditions without the radiation module, we compare experiments with different high rise building heights to identify differences in wind distribution at pedestrian level. With the radiation module activated for the same building configurations, changes in turbulent kinetic energy driven by radiation are found. In future work, we plan to extend these findings to simulations of real urban environments. The results obtained under such idealized conditions are expected to provide a basic reference for interpreting physical processes and validating model results in simulations of complex real world urban settings.