**1. Introduction**

In urban design, the settlement pattern of the buildings has very important effects on the comfort values both around the buildings and inside the buildings. For example, the microclimate in urban areas differs significantly from the microclimate in rural areas. Air temperatures in the urban texture are higher due to the urban heat island effect, and wind velocity are lower due to the roughness rates in the urban texture and the buildings block the wind flows. Spacing between buildings, street ratios and building-street relations are important in terms of providing wind environment needs of buildings, especially with urban texture ventilation. A desirable wind environment at the pedestrian level can contribute to improving the quality of urban life

for many reasons, including pollutant dispersion, city ventilation, thermal comfort and wind comfort [1–13]. In urban design, many buildings and their surroundings depend on design criteria including building height variation, and building porosity, in urban and regional planning studies to improve urban high density, low wind environments. A review of the literature studies found a strong relationship between different building heights and wind environments at pedestrian level in residential layout and open-semi-open space design between buildings [14]. In another study, the effect of different building heights on the wind speed ratio was examined and it was stated that the height variation of the building blocks could increase the wind flow motion at the pedestrian level, especially for compact conditions [15–17].

The effect of wind around buildings depends not only on the topography and the roughness of the surface, but also on the geometry of the building, the arrangement of the surrounding buildings, and the wind direction. The wind flow has multiple effects, including heat transfer by convection, penetration of rain, the dilution of the pollutants, noise or dust removal. The most significant effects on pedestrian are the mechanical and thermodynamic effects. Comfort for pedestrians is influenced by a number of variables, including wind speed (and critical speed bursts), season and the local climate, the environment temperature, rainfall, humidity, people activity in public spaces, clothing, and factors like age and psychological well-being of other pedestrians. The appearance of high wind speeds can be avoided by a preliminary assessment of the wind behavior at ground level and near buildings [18]. The major problems encountered in the evaluation of the urban microclimate are due to the heterogeneity in the land texture of the urban texture and the structure of the semi-open spaces that will create shade, and it has been seen that many problems are caused by the fact that they are not handled sensitively during the building design process [19]. Wind flow manifests itself at the pedestrian level in basically two ways: it can either be felt as a wind velocity that affects the heat exchange between people and the environment; or as a force coming from the sum of the pressure field on the human body [20].

The urban texture are usually covered by streets, designing urban streets plays an important role in creating the urban climate. The urban streets vary in geometry as defined by height/width ratio and length/width and also the orientation that is defined by its long axis. These factors have a direct bearing on solar radiation absorption and emission as well as urban ventilation, which in turn affects temperature changes in the street as well as the environment at large [21].

It has been shown that the street canyon's shape and orientation have an impact on the potential for cooling the entire urban system, solar access inside and outside of buildings, permeability to airflow for urban ventilation, and interior and outdoor habitats [22]. The most convenient urban characteristics responsible for the microclimatic variations in a street canyon, according to studies in this field, are the geometry's parameters (height-to-width ratio and street orientation) [23]. The capacity for airflow at street level, sun access, and therefore the urban microclimate are directly impacted by these factors [24, 25].
