A preliminary investigation of airflow field in designated refuge floor.

Refuge floor is specially designed in high-rise buildings for the purpose of supplying a temporarily safe place for evacuees under emergency situations. The provision of such designated refuge floor is a prescriptive requirement in the fire code of Hong Kong. Such a provision appears to be desirable by the regulators as it relates to simple rules and has administrative convenience. In order to fulfill its function, the refuge floor should be a safe place for the evacuees. The safeness of refuge floors under fire situations may be impaired if the floor is affected by smoke from lower levels. The code prescribes that cross ventilation should be provided in refuge floor so as to prevent smoke logging. However, the adequacy of such a measure and the influence of such an open floor on the rest of building have not been analytically studied. An investigation on the airflow around and inside the refuge floor is required and will provide preliminary insight on the airflow and the smoke movement patterns. In this paper, the Computational Fluid Dynamics method is employed to analyze the airflow field around and inside a refuge floor. The aim of this paper is to describe the airflow field in and around a designated refuge floor, which is the first step to explore the wind effect on the safeness of refuge floors. The study shows that airflow could be a factor affecting the smoke flow pattern.