Influencing Factors of Flammable Refrigerants Leaking in Building Air- conditioning System

This study developed a leakage model of flammable refrigerants in a building air-conditioning system, where the influencing factors of combustible gas distribution are considered including leakage rate, ventilation rate and room size. Propane is selected as refrigerant to study the effects of influencing factors on propane distribution in the room after leakage. The following conclusions are made: 1) increase of leakage rate changes the time when the ratio of dangerous area volume (RODAV) reaches 30% and the lasting time for RODAV exceeds 30%; RODAV is maintained below 30% if the leakage rate is not larger than 2.84 g/s; 2) no apparent effect of room size on concentration distribution was observed; 3) ventilation rate affects the RODAV level and propane distribution in the room, i.e. increase of ventilation rate will reduce the RODAV level and then the hazard in the building.© 2013 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the Asia-Oceania Association for Fire Science and Technology.