Gas puff

Figure 5-14 Britter-McQuaid dimensional correlation for dispersion of dense gas puffs.

Only a small fraction of the particles needed to fuel the plasma will be injected from external sources, like gas puff, neutral beams or pellets. The majority enters the plasma via recycling from divertor plates, baffles, limiters and wall. This motivates investigations about the actual recycling mechanisms. In particular, the velocities of the hydrogen particles are of interest in view of the penetration depth, and they are closely connected to the recycling mechanisms. 

Fig. 4.1. Emission spectra of H2 and D2 (left column) and of CH and CD (right column) obtained in the divertor of ASDEX Upgrade during gas puff experiments...

After its initial rise due to momentum, a dense gas puff or plume will begin to sink. Eventrrally the plume centerline strikes the ground surface. 

Shan.B., M.H. Liu, R. S. Rawat, and S. Lee, X-ray Emission Properties of Neon and Argon Plasmas in Conventional and Gas-puff Plasma Focus Devices, Proceedings of Regional Conference on Plasma Research in 21st Century, Thailand, 75-79 (2000)... 

Transfer occurs by sublimation, condensation, and diffusion (101). Printhead thermal dissipation causes donor dye to travel to the surface of the donor ribbon and convert directiy to a gas. Colorant puffs immediately strike the nearby receptor and soak in, assisted by residual printhead heat. 

Gas velocihes can also be measured with anemometers (rotating vane, hot wire, etc.), from visual observations such as the velocity of smoke puffs, or from mass balance data (knowing the fuel consumption rate, air/ fuel ratio, and stack diameter). 

Models toxic gas releases. Two models available SHELL SPILLS and TRPUF (based on EPA PUFF). Graphical output. Requires 512K memory and 132 column printer. 

TOXIC, PUFF, SPILLS, INPUFF, AND INPUFF 2.0 Bowman Environmental Engineering P.O. Bo 29072 Dallas, TX 75229 (214) 241-1895 In ascending order of data complexity, these systems address toxic gas releases using models designed for each type of release, based on emission rate, facility characteristics and weather data. 

A waterside expansive force that can be caused by a sudden drop in steam pressure without a corresponding decrease in temperature (especially in a FT boiler). Or a furnace expansive force due to the ignition of highly inflammable gas, vapor or dust. Minor furnace explosions are called puffs, flarebacks, or blowbacks. 

Enhanced oil-recovery processes include chemical and gas floods, steam, combustion, and electric heating. Gas floods, including immiscible and miscible processes, are usually defined by injected fluids (carbon dioxide, flue gas, nitrogen, or hydrocarbon). Steam projects involve cyclic steam (huff and puff) or steam drive. Combustion technologies can be subdivided into those that autoignite and those that require a heat source at injectors [521]. 

Many states now require fire suppression systems for public service stations and for some private fleet refueling facilities. Most of these systems are dry chemical using infrared detectors and work as effectively on natural gas fires as gasoline fires. No special requirements are necessary few these systems when used at a CNG refueling facility. All fire suppression systems should be checked after installation for proper coverage using a fraction of the dry chemical that would normally be used (this is called a puff test ). The puff test not only shows the coverage that will be obtained, but tests the components of the fire protection system. 

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