Positive Pressure Ventilation in Single Medium-Sized Premises

摘要

The objective of this study was to investigate the feasibility, for the fire and rescue services, of using mobile fans as a pro-active means of ventilating smoke in medium-sized premises. The efficacy of various types of such fans was therefore tested in two different-sized premises by measuring air pressures and volume flow rates in the premises. Three different types of mobile fans were used. The study was a 'cold exercise,' i.e. the effects of heat and smoke were not considered, in view of the fact that we were primarily interested in the volume flow capacity and pressure. In order better to illustrate and understand the experimental data, simple theoretical models were developed which describe how various parameters affect the results. The parameters considered in the model were the size of the supply and exhaust openings, the primary air flow of the fan, volume flow and static pressure in the building.