Fluid injecting and mixing systems for exhaust after-treatment devices

Abstract

A system for applying secondary fluids to vehicular exhaust after-treatment apparatus utilizes a mixing chamber coupled for receipt of a portion of the vehicle's exhaust flow. A source of secondary fluid is coupled to the mixing chamber and a fluid distribution element is positioned in a mean exhaust flow conduit upstream of the exhaust after-treatment apparatus. The fluid distribution element presents a preselected pattern of fluid flow toward an upstream face of the after-treatment apparatus.

1 . A system for applying secondary fluids to vehicular after-treatment apparatus, the system comprising:
 a mixing chamber coupled for receipt of a portion of exhaust flow at a mixing chamber inlet;   a source of secondary fluid in fluid communication with the mixing chamber; and   a fluid distribution element positioned in a main exhaust flow conduit upstream of the exhaust after-treatment apparatus and coupled to an output of the mixing chamber, the flow distribution element operative to present a preselected pattern of fluid flow toward an upstream face of the after-treatment apparatus.   
   
   
       2 . The system of  claim 1  wherein the mixing chamber is separate from the main exhaust flow conduit. 
   
   
       3 . The system of  claim 2  wherein the mixing chamber comprises a conduit extending substantially parallel to the main exhaust flow conduit. 
   
   
       4 . The system of  claim 1  further comprising a secondary fluid injector for injecting, under pressure, secondary fluid received from the source of secondary fluid into the mixing chamber. 
   
   
       5 . The system of  claim 1  further comprising a valve positioned in the output of the mixing chamber and operative to selectively permit and prohibit fluid communication between the mixing chamber and the fluid distribution element. 
   
   
       6 . The system of  claim 1  wherein the exhaust after-treatment apparatus comprises a particulate filter and the secondary fluid comprises filter regenerating fluid. 
   
   
       7 . The system of  claim 1  wherein the exhaust after-treatment device comprises a selective catalytic reduction catalytic converter and the secondary fluid comprises a reductant. 
   
   
       8 . The system of  claim 1  wherein the exhaust after-treatment device comprises a nitrous oxide adsorber and the secondary fluid comprises a converter substrate regenerating fluid. 
   
   
       9 . The system of  claim 1  wherein the mixing chamber is positioned within a housing of the after-treatment apparatus. 
   
   
       10 . The system of  claim 3  wherein the mixing chamber input is coupled to an exhaust manifold of the vehicle. 
   
   
       11 . The system of  claim 1  wherein the fluid distribution element comprises a perforated conduit having a series of orifices positioned with respect to the upstream face of the after-treatment apparatus so as to present the preselected pattern. 
   
   
       12 . The system of  claim 11  wherein the perforated conduit is toroidal.