Method for preventing flashback in a mixture flowing into a reaction chamber

Abstract

A method for preventing flashback in a reaction chamber that includes providing a mixture of educts flowing through a mixture distribution zone and into the reaction chamber. The mixture distribution zone has an inlet opening and a variable flow cross-section between the inlet opening and the reaction chamber. The method also includes combusting the mixture in the reaction chamber at a combustion rate, and varying the flow cross-section as a function of a volume of the mixture so as to affect a flow rate of the mixture into the reaction chamber such that the flow rate is greater than the combustion rate. In addition, a reactor that includes, an inlet opening for receiving a mixture of educts, a mixture distribution zone disposed downstream of the inlet opening and having a variable flow cross-section, a reaction chamber disposed downstream of the mixture distribution zone, and a regulation device disposed in the mixture distribution zone for varying the flow cross section.

What is claimed is:  
     
         1 . A method for preventing flashback in a reaction chamber, the method comprising: 
 providing a mixture of educts flowing through a mixture distribution zone and into the reaction chamber, the mixture distribution zone having an inlet opening and a variable flow cross-section between the inlet opening and the reaction chamber;    combusting the mixture in the reaction chamber at a combustion rate; and    varying the flow cross-section as a function of a volume of the mixture so as to affect a flow rate of the mixture into the reaction chamber such that the flow rate is greater than the combustion rate.    
     
     
         2 . The method as recited in  claim 1 , wherein the mixture distribution zone includes a plurality of flow segments and the varying of the flow cross-section includes opening or closing at least one of the plurality of flow segments.  
     
     
         3 . The method as recited in  claim 2 , wherein the varying of the flow cross-section includes increasing the flow cross-section by opening at least one adjacent flow segment.  
     
     
         4 . The method as recited in  claim 2  wherein the varying of the flow cross-section includes decreasing the flow cross-section by closing at least one adjacent flow segment.  
     
     
         5 . The method as recited in  claim 1 , wherein the mixture includes a plurality of components and the varying of the flow cross section is further performed as a function of a predefined value for metering at least one component of the mixture.  
     
     
         6 . The method as recited in  claim 1 , wherein the varying of the flow cross-section includes increasing the flow cross-section from a center region of the flow as the volume increases.  
     
     
         7 . The method as recited in  claim 2 , wherein the varying includes opening or closing each of the plurality of flow segments for a predetermined time period such that each of the plurality of flow segments is in contact with the mixture for approximately a same length of time.  
     
     
         8 . A reactor comprising: 
 an inlet opening for receiving a mixture of educts;    a mixture distribution zone disposed downstream of the inlet opening and having a variable flow cross-section;    a reaction chamber disposed downstream of the mixture distribution zone; and    a regulation device disposed in the mixture distribution zone for varying the flow cross section.    
     
     
         9 . The reactor as recited in  claim 8 , wherein the regulation device includes dividers for dividing the mixture distribution zone into a plurality of segments each having inflow openings, and wherein at least one of the inflow openings is capable of being at least partially closed.  
     
     
         10 . The reactor as recited in  claim 9 , wherein the each of the plurality of segments includes an annular duct.  
     
     
         11 . The reactor as recited in  claim 10 , further comprising a first annular covering element corresponding to a respective one of the plurality of annular ducts.  
     
     
         12 . The reactor as recited in  claim 11 , wherein the first annular covering element is moveable to a closed position in a direction of flow through the mixture distribution zone.  
     
     
         13 . The reactor as recited in  claim 11 , further comprising a second annular covering element fixedly connected to the first annular covering element and moveable to a closed position together with the first annular covering element.  
     
     
         14 . The reactor as recited in  claim 9 , further comprising at least one sheath for at least partially closing the at least one segment.  
     
     
         15 . The reactor as recited in  claim 10 , further comprising a needle and a circular center duct disposed radially inward of the annular ducts, the circular center duct being at least partially closeable by the needle.  
     
     
         16 . The reactor as recited in  claim 9 , further comprising a plurality of needles, each of the plurality of needles moveable to close one of the plurality of inflow openings.  
     
     
         17 . The reactor as recited in  claim 9 , wherein at least one of the plurality of segments includes a widening flow path along a length of the segment in a direction of flow.  
     
     
         18 . The reactor as recited in  claim 9 , wherein each of the segments further includes an outlet and wherein a ratio of each inflow cross-section to a sum of the plurality of inflow cross-sections corresponds to a ratio of a respective outlet cross section to a sum of the plurality of outlet cross sections.  
     
     
         19 . The reactor as recited in  claim 8 , wherein the reaction chamber includes a catalytically active material disposed on a carrier structure.  
     
     
         20 . The reactor as recited in  claim 8 , wherein the educts include at least oxygen, water, and a hydrocarbon-containing compound for generating a hydrogen containing gas.  
     
     
         21 . The reactor as recited in  claim 20 , wherein the water is in the form of steam.  
     
     
         22 . The reactor as recited in  claim 20 , wherein the hydrocarbon-containing compound includes at least one of diesel or gasoline.  
     
     
         23 . The reactor as recited in  claim 20 , further comprising a fuel cell operated using the hydrogen containing gas  
     
     
         24 . The reactor as recited in  claim 23 , wherein the fuel cell includes a fuel cell of an auxiliary power unit.