| 摘要 |
An internal burner for producing a subsonic air-fuel flame jet capable of flame finishing granite of similar hard stone has a body forming a closed combustion chamber fed with an essentially stoichiometric flow of compressed air and fuel such that upon ignition and combustion of the reactants, there is produced at pressures in excess of 30 psig hot products of combustion. A first nozzle within the body of relatively small diameter d1 at the exit end of the combustion chamber expands the products to supersonic velocity. A duct of sufficiently large diameter within the body downstream of the first nozzle and open thereto converts a jet of hot gases to subsonic velocity by shock action prior to discharging the hot gas products of combustion. A second nozzle having a large diameter d2 in excess of the diameter d1 of the first nozzle and open to the duct at the end opposite the first nozzle produces a subsonic flame jet to be directed against the rock surface.
|
