Auto-ignition characteristics of RP-3 kerosene under low pressure
In this paper,the auto-ignition characteristics of RP-3 aviation kerosene under a low-pressure environment are studied.According to the GB/T 5332-2007 standard,an auto-ignition point test instrument under a low-pressure environment is designed and built,and the criterion of auto-ignition,and delay time data are determined.The auto-ignition point and ignition delay time of aviation kerosene are tested under five pressure environments of 101 kPa,80 kPa,60 kPa,40 kPa,and 20 kPa.The test results show that the auto-ignition point increases with the decrease of ambient pressure.The auto-ignition point will exceed 923 K on the condition that the ambient pressure is reduced below 20 kPa,which exceeds the temperature range of the instrument.Based on combustion chemical reaction theory,the ignition process of fuel vapor is revealed,and the critical condition of auto-ignition is determined.A prediction model of auto-ignition point under low pressure is established,which agrees well with the experimental data.The influence mechanism of ambient pressure on ignition delay time is analyzed,and it is found that the ignition delay time and ambient 1/T show a linear relationship.A prediction model of ignition delay time under various ambient pressures is established,which also agrees well with the experimental data.The combustion chemical reaction of RP-3 aviation kerosene with air is analyzed,and the equivalent ratio of the combustion reaction is obtained.The actual fuel-air ratio in the experiment in this paper is calculated.Compared with the equivalent ratio,it's shown that the fuel-air ratio is higher than the equivalent ratio.Other influence factors for auto-ignition characteristics are analyzed,and it is found that the reaction container volume,wall reaction,and reactant concentration have a significant influence on the auto-ignition of liquid.The problems of GB/T 5332-2007 standard method in low-pressure condition test is analyzed,the main problem is that the vapor concentration is hard to precisely determined,and some improvement methods were put forward.
safety engineeringRP-3 aviation kerosenelow-pressure environmentauto-ignition pointignition delay time
万方数据
维普
