Patent GB-190625338-A (GB)
Title: Improvements in Apparatus for Increasing the Pressure, or Velocity of Aeriform Fluids; for Motive, or other purposes
Inventor: BOWER ANTHONY SPENCER
Filed: 1906-11-10
Granted: 1907-10-31
Abstract: 25,338. Bower, A. S. Nov. 10. Elastic-fluid turbines.-Relates to apparatus for increasing the pressure or kinetic energy of hot elastic fluids at the expense of their temperature, for use in connexion with turbines, of the kind comprising a passage in which the hot fluid expands and a second passage in which the fluid is recompressed while being cooled. The hot expansion passage A T' B and the recompression passage C T<2> D are each made of convergent-divergent form as shown, and the cooling is effected by injecting liquid spray into the fluids, arrangements being provided for approximating the velocity of the spray to that of the fluids, so that there may be no loss of efficiency due to impact. The spray is delivered directly into the mixing-chamber, through nozzles w<2> and an annular passage b, or indirectly through a nozzle w<1> in an auxiliary pipe E' through which a portion of the compressed fluid from the passage C T<2> D is returned to impart the required velocity to the spray ; this velocity may be imparted, however, by independent means, and in some cases, where the absolute pressure in the mixing-chamber is very small, it is sufficient to leave the pipe E<2> open to the atmosphere ; furthermore, the spraying-nozzle may be arranged so that the cooling is effected in stages, and the jet-cooling may be supplemented by surface-cooling, as by water-jacketing or air circulation. If the passage C T<2> D is prolonged, the velocity may be completely converted into pressure, and the fluid may then be used for driving any kind of turbine. Fig. 2 shows an apparatus, however, in which, after little or no recompression, the fluid is passed through a velocity-reducing turbine of the kind in which the fluid is made to pass through the blades twice, the outlet from one portion of the blades W communicating by a stationary serpentine passage Q with the inlet to the other portion ; the turbine is cooled by the circulation of cold air or water through the hollow blades wand the spaces R and round the turbine casing. After the fluid has passed through the turbine, recompression takes place in the passage K T<3> L. Part of the recompressed fluid is diverted through the passages N', P' for accelerating the cooling- sprays w<1>, w<3>, but if little kinetic energy remains to be converted into pressure, the passage P<2> is dispensed with, and the recompression is just made sufficient to enable the fluid to discharge into the atmosphere. It is sometimes necessary to provide auxiliary propelling means for starting and maintaining the flow of the fluid, and an ejector s<2> is shown for this purpose, but fans &c. may be employed. The fluid may be surface cooled only before entering the turbine, and in the case of parallel-flow turbines part of the recompression may take place therein. According to other features of the invention, the passages may be made of rectangular cross-section, or they may consist of two fixed parallel sides, and two relatively-movable sides, so that the compression and expansion may be regulated. When the working fluid is all or mostly steam, the apparatus may be used in combination with a superheater so that the steam is circulated in a closed circuit, that portion of steam due to the evaporation of liquid spray being rejected during each cycle. Where external cooling is employed, the heat imparted to the cooling-medium is reimparted to the fluid at some other part of the system.