Flame burning

Fixed orSlowlj M-OvingFeds. For fuel-bed burning on a grate, a distillation effect occurs. The result is that hquid components which are formed volatilize before combustion temperatures are reached cracking may also occur. The ignition of coal in a bed is almost entirely by radiation from hot refractory arches and from the flame burning of volatiles. In fixed beds, the radiant heat above the bed can only penetrate a short distance into the bed. 

Electric arc welding, flame-cutting using oxy-acetylene, propane or butane flames, or such flames burning in air. 

A fire tube contains a flame burning inside a piece of pipe which is in turn surrounded by the process fluid. In this situation, there is radiant and convective heat transfer from the flame to the inside surface of the fire tube, conductive heat transfer through the wall thickness of the tube, and convective heat transfer from the outside surface of that tube to the oil being treated. It would be difficult in such a simation to solve for the heat transfer in terms of an overall heat transfer coefficient. Rather, what is most often done is to size the fire tube by using a heat flux rate. The heat flux rate represents the amount of heat that can be transferred from the fire tube to the process per unit area of outside surface of the fire tube. Common heat flux rates are given in Table 2-11. 

Similar behavior was observed for LNG clouds during both continuous and instantaneous tests, but average flame speeds were lower the maximum speed observed in any of the tests was 10 m/s. Following premixed combustion, the flame burned through the fuel-rich portion of the cloud. This stage of combustion was more evident for continuous spills, where the rate of flame propagation, particularly for LNG spills, was very low. In one of the continuous LNG tests, a wind speed of only 4.5 m/s was sufficient to hold the flame stationary at a point some 65 m from the spill point for almost 1 minute the spill rate was then reduced. 

Burning velocity The velocity of propagation of a flame burning through a flammable gas-air mixture. This velocity is measured relative to the unbumed gases immediately ahead of the flame front. Laminar burning velocity is a fundamental property of a gas-air mixture. 

Flame speed The speed of a flame burning through a flammable mixture of gas and air measured relative to a fixed observer, that is, the sum of the burning and translational velocities of the unbumed gases. 

Similar to Figure 5.3.11, another schlieren image of a tulip flame and the remnants of the vortex, proposed to initiate the instability. The location of the vortex suggests that it forms just as the hemispherical cap flame burns out at the sidewalls. 

It is perhaps worth noticing that a measurement of flame displacement speed is trivial in this configuration however, a measurement of the flame burning rate, which is the flame speed relative to the fresh mixture, would require an additional set of measurements determining the flow velocity. This is quite different from the measurements performed in a "bomb," shown in Figure 7.1.2, where the burning rate readily deduced from the pressure rise is a nonlocal quantity averaged over the entire flame. 

It is important to update the bronchial dosimetry for radon daughters as new information becomes available. It is the purpose of this study to show that there is a potential for either significantly increased bronchial dose in the home per unit exposure if the ambient particle size is artificially reduced due, for example, to open-flame burning or use of kerosene heaters, or a decreased dose if hygroscopic particles dominate the indoor aerosol. 

Figure 10.2 Intermittency of a buoyant diffusion flame burning on a 0.3 m porous burner.

FIGURE 9.24 Transmission electron micrograph of soot particles collected from a laminar jet diffusion flame burning kerosene in air. 

Phosphine is an offensive smelling, poisonous gas which in the pure state is not spontaneously inflammable However, its temperature of ignition is very low thus, if a stream of phosphine is allowed to impinge in air on a glass vessel containing boiling water, it will immediately burst into flame, burning with considerable luminosity, in accordance with the equation —... 

Priestley believed that all materials contained an element called phlogiston , which was given off when they burned. Air in which things had been burned became less able to support combustion because it was then saturated with phlogiston . Accordingly, Priestley called his gas, in which a candle flame burned brightly, dephlogisticated air . 

SawhneyCP. 1989. Flame burns involving kerosene pressure stoves in India. Bruns 15(6) 362-364. 

Turns et al. [6] studied turbulent partially premixed flames burning methane, propane, and ethylene with air. The NO emission indices for methane and propane flames first increased and then decreased with increased levels of partial premixing. The NO emission indices for ethylene flames continuously increased at least in the limited range of partial premixing considered in the experiments. The results were qualitatively explained by the opposing effects of flame radiation and residence time on NO emissions. 

Fedele did not go to the confessionals, but to a candle stall near the door, where a single flame burned. There were two stools there, so we took one each. This time the cat refused my lap in favor of the floor, where it sat erect, staring at the friar, who ignored it. 

Good combustion is characterized by a flame burning uniformly across the piston head. Deposits and poor-quality fuel can interfere with the movement of the flame across the combustion chamber. Rough running can result. 

Action of flame, burned violently and sometimes detond... 

Action of beat, as detd by Patry(Ref 7) by placing small samples of ca 0.005g on a block Maquenne, the sample melted at 97° and then up to 245° it vaporized without decompn between 245 250°, it either decompd without flame, burned with smoky flame, or deton between 250 285° it deton vigorously betewen 285 305° it behaved in a manner similar to that described for the 245—250° range over 305° it ignited with a smoky flame without deton... 

A gas black apparatus consists of a burner pipe approximately 5 m long, which carries 30-50 diffusion burners. The flames burn in contact with a water-cooled drum, where about half of the carbon black formed is deposited. This black is scraped off and transported by a screw to a pneumatic conveying system. The gas black apparatus is surrounded by a steel box open at the bottom. At the top of it, fans suck the off-gas into filters, which collect the carbon black suspended in the gas. 

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