GB639483A - Improvements in combustion systems - Google Patents

Abstract

639,483. Generating combustion products under pressure. POWER JETS (RESEARCH & DEVELOPMENT), Ltd. Jan. 2, 1948, Nos. 209 and 5254. Divided out of 639,468. [Class 51 (i)] [Also in Group II] In a combustion system for gas turbines, using pulverulent solid fuel or heavy fuel oil, the flame is stabilized by a recirculation of hot gases to the root of the flame and the combustion is continued in an annular or circular vortex chamber having an axially-directed outlet and in which the air is given a vortex flow about the axis of the chamber. In Fig. 1, the flame tube is open to the centre of the chamber 4. The main air stream passes from the common duct 24, through swirl vanes 28, between walls 4d, 4e, and enters the chamber 4 between guide vanes 19a. Some of the air passes the vanes 19a and is conveyed by duct 17a and swirl vanes 8a to the outlet stream. Air also passes between walls 25, 26 and swirl vanes 25a. The flame tube is provided with an air-blast burner 23 and a stabilizing cup 27a. Air is admitted to the cup through swirl vanes 23a and perforations 27a. Fig. 4 shows a similar arrangement provided with a rotary disc or cup atomizer 15 rotating on a spindle 16 either with or oppositely to the vortical movement. The atomizer 15 may be located in an up-steam cylindrical extension 36, Fig. 6, of the combustion chamber throat. An annular air-stream outside the swirl vanes 18a may be provided to prevent the deposit of fuel particles on the wall of the throat. Particles larger than desired may be eliminated from the fuel-carrying stream by sending the stream through a preliminary vortex chamber with an axial outlet through which only particles of the desired size will be carried. Ash particles may be extracted from the stream of combustion products by skimming off the outside layer of the whirling stream or by putting the stream through a centrifugal separator of the vortex type. In the form shown in Fig. 9, the whirling stream enters a chamber 45 at 47 and is discharged through an outlet 46 of the same diameter. The whirling motion in the chamber is maintained by extra air entering through vanes 48. Specifications 338,108, [Class 51 (i)], 636,624 and 639,468 are referred to.