Sun & Wind
Solar Radiation in Urban Areas: Unveiling Complex Patterns and Addressing the Urban Heat Island Effect
The urban heat island effect, in which an urban area is markedly warmer than surrounding non-urban areas, will likely increase in coming decades. Understanding the modification and absorption of solar radiation and longwave radiation inside the complex urban environment is one of the key factors for climate adapted design. ENVI-met offeres sophisticated tools to assess all kind of radiative fluxes with respect to buildings, vegetation and surface materials.
Sun Analysis.
Balancing solar radiation is key in designing sun-responsive buildings, striking the right equilibrium between excessive and insufficient exposure. Façades and roofs hold utmost significance as the primary sun-exposed areas in urban settings, providing the foundation for energy-related functions within buildings, spanning solar energy utilization to cooling requirements. ENVI-met software offers efficient solar access modules, enabling swift and thorough assessments of solar radiation across all building façades, incorporating environmental factors such as vegetation.
Solar Climate.
ENVI-met software offers comprehensive microclimate analysis, ranging from short-term durations of a few days to long-term yearly assessments, including vital climate parameters like solar access. This enables accurate estimation of energy input on building façades and quantification of year-round growing conditions for plants. Benefit from detailed insights into both energy dynamics and optimal plant development throughout the year with advanced analysis capabilities.
Indexed View Sphere.
Highly reflective façades constructed with metal or glass can have a substantial impact on the local microclimate by altering the reflection of solar radiation. The presence of such materials, like aluminum, can result in a significant increase of 300 W/m² or more in the surrounding area compared to standard concrete structures. ENVI-met software incorporates the Indexed View Sphere (IVS) method, enabling precise modeling of radiation fluxes with multiple reflections and accurate estimation of thermal radiation, providing high-resolution analysis.
Exploring Solar Radiation Modeling and Analysis: High-Resolution Modeling Case Study
High-resolution modelling of solar radiation in complex environments
Building façades and roofs represent the largest proportion of sun-exposed surfaces in urban areas. The energy available at the building‘s outer envelope provides a basis to determine the energy-related processes of the building, from its solar energy harvesting potential to its cooling demand.
The module Solar Access of ENVI-met allows you to conduct a quick but comprehensive analysis of solar radiation on all building façades, taking into account the environmental factors such as vegetation.
Solar Access also generates long-term analyses of important climate parameters such as solar access and offers sophisticated three-dimensional analysis tools to calculate and trace the distribution of short-wave direct, diffuse and reflected solar radiation within the outdoor environment with a high temporal and spatial resolution.
Mitigate Wind Risk and create comfortable outdoor conditions with ENVI-met’s High-Resolution wind simulation.
The wind patterns in urban areas are both a consequence of the weather conditions and of the local planing. Facing the increase of strong wind events due to Climate Change, a wind-resilient urban design is inevitable to ensure safe and comfortable conditions for both the urban infrastructure and the residents.
Wind field.
Key to analyzing urban microclimate and air quality is the simulation of the three-dimensional wind field. This wind vector governs energy transport, pollutant dispersion, and the comfort and risk associated with wind for humans and vegetation. ENVI-met software integrates a comprehensive three-dimensional computational fluid dynamics (CFD) system, constantly adapting to evolving thermal conditions. Supported by an advanced turbulence model, it serves as the foundation for accurate microclimate and air quality simulations.
Semi-open spaces.
Semi-open spaces, like atriums, train stations, and stadiums, create unique microclimates influenced by both meteorological factors and the surrounding design. Wind and sun play pivotal roles in establishing a direct connection between these spaces and the external environment, fundamentally shaping their distinct characteristics. Understanding the interplay of wind and solar dynamics is crucial for comprehending and optimizing the microclimate within semi-open spaces.
Wind Forces.
When wind interacts with solid obstacles such as buildings, walls or vegetation, forces of motion are transferred towards the obstacle and cause mechanical reactions in it. In an urban setting, both wind direction and wind speed can vary significantly due to jet effects and vortex formations. Hence, to ensure safe building constructions and avoid wind-throw or damage of urban trees, a detailed analysis of the local flow conditions under varying wind directions is really important.
Unveiling the Complexities of Wind Flow Dynamics: High-Resolution Modeling Case Study
High-resolution simulation of the wind flow
Due to the three-dimensional structure and building arrangement within cities, it is possible to experience areas with high wind speeds and turbulent wind gusts.
The opposite situation can be found in the immediate vicinity of those areas. Zones with very low wind speed and stagnating air masses can increase the effect of heat stress, the accumulation of pollutants and promote the development of pest species in vegetation.
The wind pattern at the building canvas is an important parameter for all energetic exchange processes and for the calculation of wind loads. The three-dimensional flow model of ENVI-met allows you to conduct a detailed simulation of the flow patterns at the building facade – including the impact of facade greening.
