Natural Ventilation In Buildings 2D CFD Simulation, ANSYS Fluent Training

These days, atrium design considers natural ventilation in addition to light reflection. Residents of high-rise buildings do not benefit from the buoyancy-driven ventilation that comes from having an atrium. One way to increase buildings with varied opening areas at varying heights is to equalize ventilation and thermal comfort on different levels. Based on the novel design of Fini. et al., a CFD simulation is conducted to model Natural ventilation in buildings connected to an atrium. The proposal is published in Energy & Buildings Journal, entitled “ Effects of “wall angularity of atrium” on “buildings natural ventilation and thermal performance” and CFD model”.

Simulation Process

Although the reference paper designed a three-storied building, a high-rise building is modeled in the present CFD simulation. Figure 5 in the reference paper shows the dimensions of the atrium and buildings. The simulation is indeed carried out in two dimensions, however, for a deeper view, a 3D schematic is shown in the paper and below. The structured grid generation mitigates the cost of simulation.

Post-processing

The 2D CFD modeling of natural ventilation in buildings shows that temperature and pressure variations are the main drivers of airflow through the atrium. According to the simulation, a natural stack effect encourages upward airflow when there are pockets of higher pressure at lower levels and lower pressure at upper levels. This movement is further facilitated by temperature gradients, which cause colder air to enter via lower openings and warmer air to rise due to buoyancy effects. The convective process improves thermal comfort and indoor air quality by facilitating efficient natural ventilation