Integrated mixing system for exhaust aftertreatment system

Abstract

In one aspect, a swirl can mixer assembly for mixing a fluid with exhaust gas exhausted from an internal combustion engine is provided. The assembly includes an inlet portion including an injection area configured to receive a fluid injector for dispensing the fluid into the exhaust gas for mixing with the exhaust gas in the mixing assembly to produce an exhaust gas/fluid mixture, an outlet portion, and an extended mixing conduit fluidly coupled between the inlet portion and the outlet portion. The extended mixing conduit is curved about at least a portion of a circumference of the outlet portion to induce a swirl in the exhaust gas/fluid mixture such that the exhaust gas/fluid mixture enters the outlet portion tangentially thereto.

What is claimed is: 
     
         1 . A swirl can mixer assembly for mixing a fluid with exhaust gas exhausted from an internal combustion engine, the assembly comprising:
 an inlet portion including an injection area configured to receive a fluid injector for dispensing the fluid into the exhaust gas for mixing with the exhaust gas in the mixing assembly to produce an exhaust gas/fluid mixture;   an outlet portion; and   an extended mixing conduit fluidly coupled between the inlet portion and the outlet portion, wherein the extended mixing conduit is curved about at least a portion of a circumference of the outlet portion to induce a swirl in the exhaust gas/fluid mixture such that the exhaust gas/fluid mixture enters the outlet portion tangentially thereto.   
     
     
         2 . The assembly of  claim 1 , wherein the inlet portion is a canister having an inlet and an outlet coupled to the extended mixing conduit, wherein the outlet is located downstream of the injection area. 
     
     
         3 . The assembly of  claim 2 , wherein the canister includes a cylindrical outer surface, wherein the inlet portion outlet extends through the cylindrical outer surface. 
     
     
         4 . The assembly of  claim 1 , wherein the outlet portion is a canister having an inlet coupled to the extended mixing conduit, and an outlet. 
     
     
         5 . The assembly of  claim 1 , wherein the canister includes a cylindrical outer surface. 
     
     
         6 . The assembly of  claim 1 , wherein the extended mixing conduit includes a mixing portion and a diffusing portion, wherein the mixing portion is coupled to the inlet portion and the diffusing portion is coupled to the outlet portion, the mixing portion positioned upstream of the diffusing portion. 
     
     
         7 . The assembly of  claim 6 , wherein the cross-sectional area of the mixing portion decreases along a length of the mixing portion, the decreasing cross-sectional area configured to facilitate increasing the velocity of the exhaust gas and the fluid to facilitate mixing therebetween. 
     
     
         8 . The assembly of  claim 6 , wherein the cross-sectional area of the diffusing portion increases along a length of the diffusing portion, the increasing cross-sectional area configured to facilitate diffusion of the exhaust gas and the fluid to improve mixing therebetween. 
     
     
         9 . The assembly of  claim 6 , further comprising a mixer device located in the mixing portion of the extended mixing conduit, the mixer device configured to facilitate mixing of the exhaust gas and the fluid. 
     
     
         10 . The assembly of  claim 9 , wherein the mixer device comprises at least one of:
 a plurality of blades configured to facilitate inducing a swirl in the exhaust gas/fluid mixture; and   a middle ring configured to facilitate producing a venturi effect on the exhaust gas/fluid mixture passing therethrough.   
     
     
         11 . An exhaust gas treatment system configured to receive exhaust gas from an internal combustion engine, the system comprising:
 a catalyst device; and   a swirl can mixer assembly for mixing a fluid with the exhaust gas, the swirl can mixer assembly comprising:   an inlet portion including an injection area;   a fluid injector coupled to the inlet portion and configured to dispense the fluid into the exhaust gas in the injection area for mixing with the exhaust gas in the mixing assembly to produce an exhaust gas/fluid mixture;   an outlet portion coupled to the catalyst device; and   an extended mixing conduit fluidly coupled between the inlet portion and the outlet portion, wherein the extended mixing conduit is curved about at least a portion of a circumference of the outlet portion to induce a swirl in the exhaust gas/fluid mixture such that the exhaust gas/fluid mixture enters the outlet portion tangentially thereto.   
     
     
         12 . The system of  claim 11 , wherein the fluid injector is a reductant injector and the fluid is a reductant. 
     
     
         13 . The system of  claim 11 , wherein the catalyst device is at least one of a selective catalytic reduction (SCR) device, an oxidation catalyst (OC) device, and a particulate filter (PF) device. 
     
     
         14 . The system of  claim 11 , further comprising a second catalyst device coupled to the inlet portion. 
     
     
         15 . The system of  claim 14 , wherein the second catalyst device is an oxidation catalyst (OC) device. 
     
     
         16 . The system of  claim 11 , wherein the extended mixing conduit includes a mixing portion and a diffusing portion, wherein the mixing portion is coupled to the inlet portion and the diffusing portion is coupled to the outlet portion, the mixing portion positioned upstream of the diffusing portion. 
     
     
         17 . The system of  claim 16 , wherein the cross-sectional area of the mixing portion decreases along a length of the mixing portion, the decreasing cross-sectional area configured to facilitate increasing the velocity of the exhaust gas and the fluid to facilitate mixing therebetween. 
     
     
         18 . The system of  claim 16 , wherein the cross-sectional area of the diffusing portion increases along a length of the diffusing portion, the increasing cross-sectional area configured to facilitate diffusion of the exhaust gas and the fluid to improve mixing therebetween. 
     
     
         19 . The system of  claim 16 , further comprising a mixer device located in the mixing portion of the extended mixing conduit, the mixer device configured to facilitate mixing of the exhaust gas and the fluid. 
     
     
         20 . The assembly of  claim 19 , wherein the mixer device comprises at least one of:
 a plurality of blades configured to facilitate inducing a swirl in the exhaust gas/fluid mixture; and   a middle ring configured to facilitate producing a venturi effect on the exhaust gas/fluid mixture passing therethrough.