دانلود رایگان مقاله عملکرد احتراق صندلی قطار با سرعت بالا شعله مشتعل از طریق آزمون در مقیاس کامل

Abstract

Determining the combustion characteristics of combustibles in high-speed trains is the foundation of evaluating the fire hazard on high-speed trains scientifically, and establishing effective active and passive fire precautions. In this study, the double seats in the compartments of CRH1 high-speed trains were used as the main research object. Under different test conditions, including the power of ignition sources and ventilation rates, full-scale furniture calorimeter tests were conducted to study important fire combustion characteristics such as the ignition characteristics of seats, heat release rate, mass loss rate, total heat release, temperature variation, and smoke release rate. The relationships among these parameters were analyzed and summarized into combustion behavior and characteristics, thus providing fundamental data and reference for the development of fire precautions and safety design of high-speed trains. The results in this test are as follows: (i) The double seats of high-speed trains are relatively easy to ignite and susceptible to the fire ground environment. (ii) The combustion temperature in the test apparatus exceeded 600 °C in only 2 min for the larger ignition source. (iii) The heat release rate exceeded 800 kW. (iv) The total heat release resulted mainly from flame combustion. (v) The final mass loss rate was ∼30%. (vi) The lowest light transmittance was <25%. (vii) The change process of temperature with time has the same trend as the change process of heat release rate. (viii) Suppressing flame combustion and controlling the smoke generated from the seat materials themselves played key roles in retarding the combustion of high-speed train seats.

5. Conclusions

In this study, the double seats in the compartments of CRH1 high-speed trains were used as the main research object. A limited number full-scale furniture calorimeter tests were conducted to study the combustion behavior characteristics of these seats. Through discussion and analysis of these tests, the following indications of double seat performance in train carriages can be drawn: (1) The combustion characteristics of high-speed train double seats depend on the ignition power, ventilation rate, and other factors of fire ground environment; the ignition time appears to be mainly determined by the double seat surface material and ignition power. The combustion duration of double seats is in the range 18–26 min based on these specific test conditions. (2) The heat release rate of high-speed train double seats can exceed 800 kW, mainly dominated by the combustion of the polyurethane filler of cushion; the ventilation conditions significantly affected the peak value of heat release rate. (3) The THR exceeded 300 MJ. Therefore, means to suppress the flaming combustion of seats is the key factor in retarding double seat fires; the final mass loss rate was 30%. (4) The combustion of high-speed train double seats generates a large amount of high-temperature smoke. In these tests, the shortest time to achieve flaming combustion and a high temperature of 600 8C is 2 min. (5) The SRR increased and the light transmittance decreased with the increase in ignition power and ventilation rate. The minimum value of light transmittance was <25%. Reducing the smoke generated by double seat materials is one potential measure to minimize casualties. Understanding the fire behavior of seats on high speed train is one important factor, along with all ceiling and floor materials in designing trains in which the risks to train passengers and crews are minimized. This limited test program has identified some of the key factors in the interval train carriage environment which can affect train seat fire performance.