Spark ignition energy

Materials having low minimum spark ignition energies, or autoignition temperatures... 

Tbe partial results are shown in Figure 2-6.2.1. Tbe ranges of ignitable concentrations are superimposed on a spark ignition energy curve for bexane in air calculated from data in [56]. Both data sets are assumed to be characteristic ofn-hexane, unbiased by the presence of methylcyclopentane or hexane isomers (dimethylbutanes and methylpentanes). 

Several of the combustion-related properties of hydrogen in air, such as its wide flammability limits (4-75 vol%), wide detonation range (20-65 vol%), very low spark ignition energy (0.02 mJ), high heat of combustion (121 kJ/g) and high flame temperature (2050°C) combine to emphasise the high fire-related hazards of the... 

FIGURE 7.5 Correlation of the minimum spark ignition energy with quenching diameter (from Calcote et al. [15]). 

H. Minimum Spark Ignition Energies and Quenching of Hydrocarbon... 

Table 1. Minimum spark ignition energy data for fuels in air at 1 atm pressure...

TABLE HI Minimum Spark Ignition Energy Data for Fuels in Air at 1 atm Pressure... 

Values of n are available for numerous gases and gas mixtures. Burning velocities have been measured on burner flames, and flame temperatures, Tb, can be computed thermodynamically. It is thus possible to put Equation 5 to a test by comparing experimental values of minimum spark-ignition energies with values calculated from data on quenching distances, burning velocities, heat conductivities, and flame temperatures. 

Minimum Spark Ignition Energy of Fuels. Determination of the minimum energy required for ignition of fuel by a spark is another way of measuring the intrinsic resistance of a fuel to ignition. Metzler has measured the minimum spark ignition of various fuels. Table XI shows that at atmospheric pressure in a bomb, paraffins, branched... 

Electrostatic discharge—Any metal or good conductor of electricity can store enough, electrical energy to exceed minimum spark ignition energy for dust and vapor clouds (25 mJ for most of the hydrocarbons). To prevent such... 

Substance Ignition temperature (°C) Minimum spark ignition energy (ml) Lower explosive concentration (mg/m )... 

The minimum energy for ignition is measured primarily to determine whether the dust cloud could be ignited by an electrostatic spark. Ignition energies of dusts can be as low as 15 mj this quantity of energy can be supplied by an electrostatic discharge. 

---