Premix burner arrangement for operating a combustion chamber and method for operating a combustion chamber

Abstract

A premix burner is disclosed for operating a combustion chamber with a gaseous and/or liquid fuel, having a swirl generator for inducing a swirl flow in an incoming combustion air flow and a device for injecting fuel into the swirl flow, the swirl generator having at least two cone shell segments which fit together to form a flow body and together enclose a conically formed swirl space with a cone angle γ and air inlet slits directed tangentially to the length of the cone. At least at the downstream end region of the swirl generator, a shaped element enclosing the cone shell segments with an inside wall facing the cone shell segments is provided, and that the cone shell segments end in the inside wall in a flush manner while maintaining their shape.

1 . A premix burner for operating a combustion chamber with a gaseous and/or liquid fuel, comprising: 
 a swirl generator for inducing a swirl flow in an incoming combustion air flow; and    means for injecting fuel into the swirl flow, the swirl generator having at least two cone shell segments which fit together to form a flow body and together enclose a conically formed swirl space with a cone angle γ and air inlet slits directed tangentially to the length of the cone, wherein the cone angle γ is greater than or equal to 20° and the swirl generator has a downstream burner diameter of greater than 180 mm, and wherein, at least at the downstream end region of the swirl generator, a shaped element enclosing the cone shell segments with an inside wall facing the cone shell segments is provided, and wherein the cone shell segments end in the inside wall in a flush manner while maintaining their shape.    
   
   
       2 . The premix burner as claimed in  claim 1 , wherein the shaped element encloses the cone shell segments at their downstream end region in an annular manner in such a way that the inside wall of the shaped element is connected in each case to the cone shell segment by means of a line of intersection through the respective cone shell segment, along which the cone shell segment virtually penetrates the inside wall while maintaining its shape.  
   
   
       3 . The premix burner as claimed in  claim 1 , wherein the inside wall is frustoconically formed and has a contour tapering conically in the direction of flow.  
   
   
       4 . The premix burner as claimed in  claim 1 , wherein the inside wall has adjoining the swirl generator directly downstream an inflow region in which the inside wall is formed tapering in a funnel-shaped manner in the direction of flow.  
   
   
       5 . The premix burner as claimed in  claim 4 , wherein the inside wall has in the inflow region a curvature contour formed in longitudinal section as a quarter ellipse.  
   
   
       6 . The premix burner as claimed in  claim 4 , wherein downstream of the inflow region the inside wall goes over into a flow portion which has a flow cross section remaining the same in the direction of flow.  
   
   
       7 . The premix burner as claimed in  claim 1 , wherein the inside wall is cylindrically formed.  
   
   
       8 . The premix burner as claimed in  claim 3 , wherein the first shaped element is adjoined in the direction of flow by a further shaped element, with a further inside wall, which axially has a constant flow cross section.  
   
   
       9 . The premix burner as claimed in  claim 1 , wherein at least four cone shell segments are provided to form the swirl space.  
   
   
       10 . The premix burner as claimed in  claim 1 , in combination with a silo combustion chamber, wherein the premix burner is configured to fire the silo combusion chamber.  
   
   
       11 . The premix burner as claimed in  claim 2 , wherein the inside wall is frustoconically formed and has a contour tapering conically in the direction of flow.  
   
   
       12 . The premix burner as claimed in  claim 2 , wherein the inside wall has adjoining the swirl generator directly downstream an inflow region in which the inside wall is formed tapering in a funnel-shaped manner in the direction of flow.  
   
   
       13 . The premix burner as claimed in  claim 5 , wherein downstream of the inflow region the inside wall goes over into a flow portion which has a flow cross section remaining the same in the direction of flow.  
   
   
       14 . The premix burner as claimed in  claim 2 , wherein the inside wall is cylindrically formed.  
   
   
       15 . The premix burner as claimed in  claim 7 , wherein the first shaped element is adjoined in the direction of flow by a further shaped element, with a further inside wall, which axially has a constant flow cross section.  
   
   
       16 . The premix burner as claimed in  claim 5 , wherein at least four cone shell segments are provided to form the swirl space.  
   
   
       17 . The premix burner as claimed in  claim 6 , wherein at least four cone shell segments are provided to form the swirl space.  
   
   
       18 . The premix burner as claimed in  claim 5 , in combination with a silo combustion chamber, wherein the premix burner is configured to fire the silo combusion chamber.  
   
   
       19 . The premix burner as claimed in  claim 6 , in combination with a silo combustion chamber, wherein the premix burner is configured to fire the silo combusion chamber.