Optimization research on smoke prevention and exhaust system for air-bearing membrane structure buildings

Due to its advantages in energy conservation, emission reduction and recyclability, air-supported membrane structure (ASMS) has been widely implemented in various applications, including large stadiums, conference centers, warehouses and temporary buildings. Compared to traditional building, the structural and material properties of ASMS are special which significantly affect smoke diffusion and flow behavior during fire scenarios. Moreover, the design methods for smoke management system of ASMS buildings are still lacked and further research is required. In this study, a numerical model of a coal storage bin was built. The impact of several key design parameters, including such as height of natural smoke vent, fire source location and makeup air methods, on the performance of ASMS building`s smoke management system were evaluated. Gas temperature, CO concentration, visibility, smoke exhausting quantity, critical pyrolysis temperature and critical heat radiation intensity were selected as evaluation indexes. The results indicated that better natural smoke exhaust efficiency was achieved when the natural smoke vents were located at the height between 80% and 100% of the building’s total height. Setting natural makeup air vent in the wall of smoke bay 3 can achieve the best cooling effect. However, compared to natural makeup air, the natural smoke exhaust efficiency of mechanical makeup air was much better. When the rate of mechanical makeup air reached 120% of the required natural smoke exhausting quantity, it has significant improvements in temperature reduction, visibility and natural smoke exhausting quantity which are crucial for ensuring safe evacuation during fire events. These findings provide a design refer for enhancing fire protection and construction practices in ASMS buildings.