Fire Safety of Complex Buildings – Smoke Models and Application скачать в хорошем качестве

Fire Safety of Complex Buildings – Smoke Models and Application

Dr Luo's talk will relate to the design of a large metro system, an international airport terminal, and a mega depot. It will tell engineers the gap between scientists’ research results and practical design applications, and how engineers can make use of the existing models to solve the problems that no existing solution is available. For large and complex buildings, smoke control system plays an important role in life safety and property protection. Smoke models are the tools for the design of the smoke control system. Since the 1970s, scientists developed semi-empirical models to describe smoke movement, but engineers encountered three major issues raised from practice. Firstly, several plume models are available to estimate the smoke production rate and the capacity of the smoke extraction fan, but their discrepancy or accuracy is unclear. Secondly, the phenomenon of stratification affects the vertical transportation of smoke, and influence the activation time of the detectors and the efficiency of the smoke extraction system. A stratification model is available from literature to calculate the maximum height that the smoke can rise, but it cannot cover all design scenarios. Thirdly, the size of the smoke reservoir has been regulated in fire regulation. The regulation does not consider the factors that strongly affect the movement of smoke in the reservoir, such as the ceiling height, the shape of the reservoir, the temperature of the smoke, etc. It is found that the models developed by scientists are difficult to directly apply for a specific project. It is also found that some clauses of the fire regulation do not address the requirements correctly and become a hurdle of deign. This presentation depicts the cases encountered during the design in the past years and provides the details of the process of solving these issues. The approach of the design process demonstrates how fire engineers further develop the fire models by scientists and fill the gap between the scientists’ research and application in practice. Refer to the fire safety design of metro system, airport terminal building, and mega depot projects, this talk will systematically examine the fire smoke models for the plume, vertical transportation of the smoke, the ceiling jet, and smoke spreading underneath the flat ceiling, and provides practical solutions for each of the smoke development stages.