Air blasting

I. G. Bowen, E. R. Fletcher, and D. R. Richmond, Estimate of Man s Tolerance to the Direct Effects of Air Blast, DASA-2113, Defense Atomic Support Agency, Washington, D.C., 1968. 

Containerized ice cream is hardened on a stationary or continuous refrigerated plate-contact hardener or by convection air blast as the product is carried on a conveyor or through a tunnel. Air temperatures for hardening are —40 to —50° C. The temperature at the center of the container as well as the storage temperature should be <—26°C. Approximately one-half of the heat is removed at the freezer and the remainder in the hardening process. 

Drying of the air blast lowers coke usage 3% for each 1% of water vapor removed. 

Liquid fuel is injected through a pressure-atomizing or an air-blast nozzle. This spray is sheared by air streams into laminae and droplets that vaporize and bum. Because the atomization process is so important for subsequent mixing and burning, fuel-injector design is as critical as fuel properties. Figure 5 is a schematic of the processes occurring in a typical combustor. 

FIG. 12-48 Doiible-tnick dryer. (A) Air-inlet duct. (B) Air-exhaiist duct with damper. (C) Adjnstahle-pitch fan 1 to 15 hp. (D) Fan motor. (E) Fin heaters. (F) Plenum chamber. (G) Adjustable air-blast nozzles. (H) Trucks and trays. (J) Turning vanes. 

With the availability of 3.3 and 6.6 kV vacuum contactors the control of HT motors up to 6.6 kV systems has now become easier and economical, compact and even more reliable. For 11 kV. systems, vacuum as well as SF (Sulphur hexafluoride) breakers can be used. The HT motor s switching and protection through a vacuum contactor provides a replica of an LT system. The earlier practice of using an HT OCB, MOCB, or an air blast circuit breaker for the interruption of an HT circuit is now a concept of the past. 

This practice is usually adopted in oil circuit breakers (BOCBs and MOCBs). In air blast circuit breakers (ABCBs), and SF(, circuit breakers, a resistance is connected in shunt across the contact gap. such that R is introduced in the circuit during the making and interrupting processes only. 

Figure 19.13(b) Process of arc formation and quenching in an air blast circuit breaker... 

No, because of force of air blast even at small currents which may develop the tendency to current chopping. On the other hand, il is possible that the breaker may fail to interrupt the sleep fronted TRVs... 

Thunderous noise during an interruption, because of air blast. The intensity can be controlled by providing silencers... 

Air blast, explosion, or earthquake. Nearby unbalanced macliinery. Blows, impact. Present in all rotating machinery. 

Wiederman, A. H. 1986a. Air-blast and fragment environments produced by the bursting of vessels filled with very high pressure gases. In Advances in Impact, Blast Ballistics, and Dynamic Analysis of Structures. ASME PVP. 106. New York ASME. 

White, C. S., R. K. Jones, and G. E. Damon. 1971. The biodynamics of air blast. Lovelace Foundation for Medical Education and Research. Albuquerque, NM. 

Wimperinfusorien, /.pi. (Zodl.) CiUata. wimperad, p.a. ciliated, ciliary winking. Wind, m. wind, breeze air blast. -blSser, m. 

Air blast circuit breakers are insulated by air, and the plasma is extinguished as a blast of compressed air is blown between the contacts. These are less common than the other types and generally are no longer... 

Air circuit breakers can be either air break types (which utilize atmospheric air) or air blast (which use compressed air). Air-break type breakers extinguish the arc by high-resistance interruption, the arc being controlled within an... 

Air-blast circuit breakers operate on the low-resistance principle the arc length is minimized and a blast of air is directed across the arc to cool and remove ionized gas. Air break circuit breakers are now used extensively at medium voltages while air blast circuit breakers have been employed up to the highest voltages. 

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