Combustor

Claim 1

A combustor comprising: a. a hollow housing means; b. first and second hollow members disposed within said housing means with a substantial portion of their axial lengths in radially spaced-apart axially overlapping relationship to define with said housing an inlet and an outlet and axiallyspaced primary, secondary and tertiary combustion zones therebetween; c. means including a plenum adapted for connection with a supply of air under pressure; d. means to supply a controlled flow of fuel to said primary combustion zone; e. means communicating with said plenum and said primary combustion zone for supplying a controlled forced flow of air to said primary combustion zone having a given direction helical motion operative to effect a fuel rich burning mixture wherein the hot combustion gases are confined to a narrow zone along the longitudinal center thereof; f. means to ignite the combustible materials in said primary combustion zone; g. first annular air passage means defined by the radially spaced confronting surfaces of said first and second hollow members and communicating at one end with said plenum and at the other end with said secondary combustion zone; h. second annular air passage means defined by the radially spaced confronting surfaces of said housing means and said first hollow member and communicating at one end with said plenum and at the other end with said tertiary combustion zone, said first and second annular air passage means each including means operative respectively to control the flow of air to each of said secondary and tertiary combustion zones to complete the combustion process in staged combustion; i. first fin means comprising a plurality of circumferentially spaced-apart fins helically disposed on the outer surface of said first hollow member and extending into said first air passage means so that the air flowing therein has said given direction helical motion imparted to it and cools said first hollow member and the flame in said primary combustion zone before introduction as combustion air to said secondary combustion zone and wherein the helical motion is operative to confine the hot combustion gases of said secondary combustion zone to the longitudinal center thereof; and j. second fin means comprising a plurality of circumferentially spaced-apart fins helically disposed on the outer surface of said second hollow member and extending into said second air passage means so that the air flowing therein has helical motion imparted to it and cools said second hollow member and the flame in said secondary combustion zone before introduction as combustion air to said tertiary combustion zone.