GB1341188A - Chimney pulsing device - Google Patents

Abstract

1341188 Fluid regulation NATIONAL RESEARCH DEVELOPMENT CORP 18 Jan 1971 [23 Jan 1970] 3443/70 Heading G3M [Also in Division F4] A fluid pulsing device 10, which is designed for controlling the output of a chimney such that the smoke is discharged in the form of smoke rings, takes the form of a diverter assembly having static deflectors (shaded), an elongate reservoir 16 which may be open at its lowermost end, an input passage 11 which communicates with the exhaust passage of a boiler 26, and an output passage 13, a control pipe 20 extending centrally of the assembly. In use, smoke entering input passage 11 is diverted to the reservoir 16 and during its passage thereto tends also to entrain smoke present in the outlet 13. Subsequently, a control air jet is passed through pipe 20 and this acts to modify the smoke flow path such that it passes from the input passage 11 to the outlet 13 and in so doing entrains smoke present within the reservoir 16. Termination of the control air jet results in a return to the initial gas flow pattern. Accordingly, smoke is emitted from the outlet 13 only for the duration of a control pulse within pipe 20. To ensure a proper termination of the outflow of smoke from output 13, a terminator in the form of a plurality of air nozzles 22 is arranged adjacent to the output passage terminal portion, the nozzles being arranged to direct air in a direction towards the input passage. The air used in passage 20 and nozzles 22 is derived from a circuit 27, 29, 30, 31, 32, 33 and is controlled by an electric timing circuit 38 acting on valves 36, 37 such that air is supplied alternatively to the passage 20 and the nozzles 22. Various modifications of the pulsing device and associated control circuitry are depicted in Figs. 1-2 and Figs. 4-6, (not shown).