Papers by Keyword: Ignition Temperature

Abstract: Heating and cooling activities of buildings consume a considerable amount of energy used in building envelopes and are responsible for almost 16 % of CO2 emissions in the air. This problem has been confronted with a recent worldwide trend by introducing eco-friendly buildings with net zero emissions. Currently used thermal insulators in building envelopes are usually made from synthetic polymers which are difficult to recycle or dispose of. This paper presents a novel bio-composite mats using Egyptian pulled wool fiber waste and flax fibers waste as an alternative to commercial polystyrene foam. High loft nonwoven mats with different blends of wool and flax are fabricated and characterized to utilize a composite structure with satisfactory thermal and physical properties. Thermal conductivity test, ignition test, and compression and recovery test are applied to the developed specimens. The results proved the competitiveness and suitability of the proposed composites to be used as building interior insulators when compared to polystyrene and other similar composite materials from literature.

Abstract: The possibility of using polymers based on epoxyphenolic binders to obtain fiberglass with an intense level of carbonization has been investigated. The correlation between the pyrolytic transformations intensity and the fire hazard indicators of polymers is shown. It is established that the conditions for the intensive passage of pyrolytic reactions are facilitated by the presence in the matrix system of conjugated aromatic (naphthalene) radicals. The C/H ratio in the carbonized layer is confirmed by the data of IR spectroscopy both at the preparation stage and after exposure to characteristic temperatures.

Abstract: Based on analysis of appropriate literary sources we established that estimation of fire separation distances was based of two criteria: heat flux and temperature. We proposed to use “ignition temperature of materials” as principal criterion when determining fire separation distances between adjacent construction facilities. Based on the results derived while performing complete factorial we created mathematical model to describe trend of changing fire separation distances depending on caloric power of fire load (Q), openings factor of the external enclosing structures (k) and duration of irradiation (t); moreover, its adequacy was confirmed. Based on linear regression equations we substantiated calculation and tabular method for the determination of fire separation distances for a facility being irradiated which contains combustible or otherwise non-combustible façade and a facility where liquid oil products turn. We developed and proposed general methodology for estimation of fire separation distances between construction facilities by calculation.

Abstract: The development of the new technologies has also brought new possibilities of the wood processing, wood shaping and wood materials tending. By reason of increased human need for wood products the industry has shifted from the production in the workshops throught manufactures up to fabrications. This fact also causes increasing of the wood dust amount in the spaces of the production shops or halls, and by that also increased danger of the explosion of the wood dust. At the adequate initiatory source, sufficient amount of flammable material, oxidant and essential pressure, the explosion can occur and last for several miliseconds, therefore people rescue in the endangered spaces in case of explosion is impossible. One of the parameters which influence properties of the flammable wood dust is its particle size. The article deals with the particle size influence of the wood dust at its minimal temperature of ignition in the stired state. On the basis of the experimental measures the influence of the minimal action of the thermal energy for the activation of the ignition process of the wood dust in the stired state at the reacting of pressure and variousness of grit size is assessed.

Abstract: Article discusses effect of environmental condition on heat transfer from wood sample during burning process. The aim of the paper is to characterize temperature vs time dependence of irradiated wood surface as a function of heat source distance , total heat transfer coefficient and thermal diffusivity . From temperature vs time dependence on the irradiated side is possible to compute heat ignition temperature of wood as one of the most important characteristics of wood burning. All measured values of studied parameters are in very good agreement with table values.

Abstract: Ignition temperature is an important parameter in fuel combustion characteristics research. In this paper, tradition ignition temperature determination methods and their application limitations were discussed by analyzing the DTA curve. All discussions were demonstrated in sweet sorghum fermentation residue particles combustion test. As commonly-used methods were totally established with no consideration of thermal analyzing, the calculating value error were obvious. Taking account detected time t_k (uV>0) and delay time() in DTG (derivative thermogravimetry)-DTA (differential thermal analyses) profile, DTG-DTA delay time method was established in this paper. The calculated values comparison has been performed between new method and TG-DTG dividing point method，the latter was recognized as the most accurate method. It was showed that new method has almost the same ignition temperature to that of TG-DTG dividing point method. While new method needs only half workloads of TG-DTG diving point method. The physical conception of new method is clear and corresponded ignition temperature is accurate. Therefore, new method is suitable for biomass ignition temperature determination.

Abstract: This paper studied gasoline vapor combustion catalyzed by Pd/Al₂O₃ in oxygen-poor condition. By adjusting the gasoline vapor and oxygen, the inlet temperature and flow rate, collecting data of temperature difference between outlet and inlet as well as the change of gas mixture, the study analyzed the various factors in the catalytic combustion process, and optimized the process control parameters. The results indicated that catalytic combustion was more efficient at the ignition temperature of 274 °C, burned 50% of gasoline vapor in oxygen-poor condition (O₂ fraction was 12%).

Abstract: Today, magnesium (Mg) alloys are recognized alternatives to iron and aluminum to reduce the weight of structural materials. This contribution was performed to provide information on the flammability of magnesium alloys through investigation of the ignition temperature of selected Mg alloys. The test was performed in a muffle furnace with dynamic heating program. Also were performed tests of chemical composition of studied specimens.

Abstract: The paper focuses on the high-temperature oxidation of a crude oil in a forward in-situ combustion process. The reaction conforms to Arrhenius prescription. Based on Semenov’s definition of ignition, equations for calculating the ignition temperature and stable combustion temperature are derived from the heat balance of the high-temperature oxidation. With previous experimental data, an average empirical parameter of the equations is calculated and two predictive equations are got. It’s concluded from the equations that these two temperatures of the reaction are only dependent on crude properties, and other factors in the reservoir have little influence on them.

Abstract: The window glass ignition temperature is one of the main factors that determine the Heat Release Rate (HRR) of passenger rail car. In order to reveal the influence of window glass ignition temperature on the HRR of China Railways High-speed (CRH) passenger rail car, the HRR, ignition temperature and other thermal parameters of the individual materials and component assemblies of the CRH passenger rail car, are measured with the Cone Calorimeter, burning temperature tester and other instruments, as the input parameters of Fire Dynamics Simulator (FDS), and according to the different window glass ignition temperatures ,4 fire scenarios have been designed to obtain the HRR vs. time curves of CRH passenger rail car. The comparison results show that the window glass ignition temperature exerts a significant influence on the HRR of passenger rail car; if the ignition temperature is lower than 415°C, during the fire process the windows near the ignition source will be broken, and the back draft phenomenon will take place, resulting in the extremely high second peak HRR, about 22.6MW; if the ignition temperature is higher than 470°C, during the fire process all the windows will not be broken; and so it is suggested that the window glass ignition temperature in the passenger rail car should be higher than 520°C.