Reduced scale tests on combustion efficiency in compartment fire with small openings

The objectives of this study are to investigate the relationship between the combustion efficiency in a fire compartment with small openings and the compartment geometry including openings and fire source location, and to discuss whether this combustion efficiency can be predicted from reduced-scale tests. The scale law on combustion efficiency was developed. Experiments were conducted using two compartments varying in linear size by a factor of 2 but geometrically similar in their over-all proportions. Different combustion efficiencies were observed due to the shape of opening and the place of fire source under the conditions with same ventilation factor. The measured combustion efficiencies in the two geometrically similar enclosures showed good agreement, which validated the scale law on combustion efficiency under the condition with 1.0 of equivalence ratio examined in this study.