Ignition behavior

F. P. McCuUough and B. C. Goswami, "Novel Fibers and Their Ignition Behavior," Hi-Tech Conference, Clemson University, S.C., July 21,1993. 

As far as extinction/ignition behavior is concerned, oxidations in micro reactors can exhibit varied temperature profiles [19, 56, 57, 59-61]. As a consequence of their very distinct heat transfer characteristics, micro reactors can allow autofhermal operation at a different temperature level compared with processing in conventional reactors. As an example, this may raise the selectivity of value products. 

This new burner concept (see Fig. 3.26) was tested with very positive results. The new control reduces emissions and improves the ignition behavior by adjusting the gas supply to the actual air volume. At the same time, the performance of the burner system can be adapted within a wide heat load range without increasing the emission of pollutants, as the sensor keeps the gas-to-air ratio always constant. 

Saito with a fine wire thermocouple embedded at the surface [3]. The scatter in the results are most likely due to the decomposition variables and the accuracy of this difficult measurement. (Note that the surface temperature here is being measured with a thermocouple bead of finite size and having properties dissimilar to wood.) Likewise the properties k. p and c cannot be expected to be equal to values found in the literature for generic common materials since temperature variations in the least will make them change. We expect k and c to increase with temperature, and c to effectively increase due to decomposition, phase change and the evaporation of absorbed water. While we are not modeling all of these effects, we can still use the effective properties of Tig, k, p and c to explain the ignition behavior. For example,... 

Lead Azide. See in Encycl, Vol 1, A545—A587 Addnl Refs 1) B. Reitzner, Influence of Silver Coatings on Ignition Behavior of Colloidal Lead Azide , PATR FRL-TR2 (1960), PB148915 2) B. Reitzner, Influence of... 

It is known that much of the antimony is vaporized during burning30 or char formation.28 The ignition behavior of polyester resins inhibited by antimony halogen systems has been considered to indicate the likelihood of gas-phase inhibition.23-24... 

The works of French scientists demonstrate considerable potential in the study of the chemieal aspects of ignition. It has been shown in Ref. that the addition of ferrocene to poly(vinyl chloride) strongly affects the self-ignition behavior of the polymer. Various glow phenomena are then observed which usually do not... 

In the neighborhood of 300 to 400°C, the aliphatic hydrocarbons from ethane on up show a rather complex ignition behavior (Fig. XIV. 10). At... 

For every installation, a check has to be made to determine which ignition source may become effective and whether it can be prevented with a sufficient degree of safety. With more sensitive products and complex installations, it becomes more and more difficult to exclude ignition sources with ample safety (Siwek et ak, Ignition Behavior of Dusts, Proc. Loss Prevention Symposium, Atlanta, April 12—19, 1994). 

Following this lead, Martin and coworkers proceeded with acquisition of further data to clarify the ignition behavior of cellulose, but they rejected the use of ElR as being artificial because of the substantial variation in the overall weight-loss activation energy among the cellulosic materials. However, they found that the hypothetical, heat-flow model serves as a convenient device for correlation of their experimental results and the interpretation of the ignition behavior. 

The resulting expression for the ignition behavior of cellulose in terms of the parameter groupings derived from the heat-conduction, theoretical model is shown in Fig. 11. It may be noted that, for small values of the Fourier modulus (short times or thick materials), tran-... 

Further attempts have been made to interpret the ignition behavior of cellulose in terms of temperature profiles attained during exposure and evolution of combustible volatiles. 

The results of the studies presented above clearly demonstrate that SFG surface vibrational spectroscopy, when combined with appropriate calibration measurements, is a promising experimental method for bridging the pressure gap as well as the materials gap which separate the UHV single-crystal model studies from technical catalytic investigations. Further experimental work is under way in which the method developed in the present work will be applied to investigate the influence of surface structure, mixture composition and pressure on the ignition behavior of the CO/02/Pt-system and other reactants/surface-systems under technically relevant conditions. 

---