Sub-atmospheric pressure effects on pool fire behaviors using n-heptane with water mist based on the protection of the ozone layer in aircraft operation safety. Twin-fluid water mist has been evaluated as one of the most promising technologies to replace Halon fire suppressant for cargo fires. N-heptane pool fires with no water mist suppression activated and with water mist fire suppression system activated were tested and analyzed under standard pressure and different depressurization rates (91, 182, 328 Pa/s) in this work. The mass loss of fuel and chamber pressure history were measured. In addition, the suppression time for each test with water mist activated was also analyzed statistically. The test results under different depressurization rates demonstrated the effectiveness of the water mist system, and the average suppression time is less than 25 seconds. The different pressure ratios between water and nitrogen have also been compared and analyzed, and the results show that the suppression is more effective when the pressure of the water and nitrogen is 0.4 MPa and 0.48 MPa, respectively. The outcomes are of great significance for optimizing the design of fire extinguishing systems for aircraft.
Keywords Twin-fluid Water Mist, Pool Fire, Changed Pressure, Low Pressure, Fire Suppression