Study On The Pyrolysis Combustion And Thermal Response Of Aircraft Cargo Compartment Sidewall Liners In Fire Environment

In order to conduct in-depth research on the prevention and control of the spread of cargo compartment fires in civil aircraft and to support the investigation of aircraft fire accidents,a composite material product of the sidewall liners of a certain type of aircraft cargo compartment was selected as the object,and experimental research on the pyrolysis combustion characteristics and thermal response behavior was conducted.Based on the experimental data,a series of corresponding model was established.The main conclusions obtained in this paper are as follows:The research platform for pyrolysis characteristics,combustion characteristics and high temperature environment thermal response behavior of aircraft cargo side liner material were built.The pyrolysis characteristics and pyrolysis kinetics analysis of cargo sidewall liner material under different heating rates,the influence of external radiation intensity on the combustion characteristics of the material,the comprehensive fire risk assessment and thermal response behavior research were carried out.The experimental results show that the increase of heating rate will lead to the temperature of the weight loss curve and the maximum weight loss rate moving to the high temperature region,and there are two pyrolysis stages.The average apparent activation energy calculated by FWO and KAS non-model methods were 213.64 k J / mol and 233.84 k J / mol,respectively.With the increase of thermal radiation intensity,the ignition time decreases,the peaks of heat release rate,mass loss rate,carbon monoxide content and carbon dioxide content arrive in advance and increase,and the comprehensive fire risk of materials increases.The thermal response behavior under different high temperature heat sources can be divided into three stages,namely,the steady stage of thermal response,the stage of material change and the stage of material damage.By analyzing the intrinsic relationship between the ignition time of the sidewall liner materials and different radiation intensities,a predictive model for ignition time during combustion was established.Additionally,by simplifying the three-step and five-step parallelsequential reaction pyrolysis process in nitrogen and air atmospheres,a comprehensive fivestep reaction pyrolysis model was established.The thermal response model is proposed and validated,it was shown that there is good agreement between the calculated values of the model exhibit with experimental values.