Exhaust Aftertreatment System with Flow Distribution

Abstract

An exhaust aftertreatment system has a side inlet flow diffuser and provides even flow exhaust distribution to an aftertreatment element.

1 - 8 . (canceled) 
     
     
         9 . An exhaust aftertreatment system comprising an exhaust conduit carrying exhaust to an aftertreatment element treating said exhaust, said conduit comprising an L-shaped bend having first and second legs meeting at an L-shaped junction, said second leg extending axially along an axis along an axial direction and directing exhaust to said aftertreatment element, said first leg extending laterally along a lateral direction relative to said axis and directing exhaust to said second leg, a flow distributor at said L-shaped junction and re-distributing exhaust to flow from said first leg to said second leg in an evenly distributed flow pattern to flow axially along said second leg to said aftertreatment element, wherein said flow distributor is a perforated member having a variable perforation pattern, wherein said flow distributor has an inlet end receiving exhaust flowing laterally thereinto, and a distal end laterally distally oppositely spaced from said inlet end, and said variable perforation pattern provides a diffuser outlet flow area which decreases as exhaust flows from said inlet end toward said distal end. 
     
     
         10 . The exhaust aftertreatment system according to  claim 9  wherein said variable perforation pattern comprises decreasing density of perforations from said inlet end toward said distal end. 
     
     
         11 . The exhaust aftertreatment system according to  claim 9  wherein said variable perforation pattern comprises decreasing size of perforations from said inlet end toward said distal end. 
     
     
         12 - 14 . (canceled) 
     
     
         15 . An exhaust aftertreatment device comprising a housing extending axially along an axis and having an upstream inlet for receiving exhaust and having a downstream outlet for discharging exhaust, said inlet being a side inlet receiving exhaust flowing laterally into said housing relative to said axis, an aftertreatment element in said housing passing exhaust axially therethrough then to said outlet, a flow distributor receiving exhaust flow laterally from said inlet and re-distributing exhaust to flow axially to said aftertreatment element in an evenly distributed flow pattern, wherein said flow distributor comprises a perforated diffuser tube having a variable perforation pattern providing a diffuser outlet flow area which decreases as exhaust flows laterally away from said inlet. 
     
     
         16 . The exhaust aftertreatment device according to  claim 15  wherein said variable perforation pattern comprises decreasing density of perforations as exhaust flows laterally away from said inlet. 
     
     
         17 . The exhaust aftertreatment device according to  claim 15  wherein said variable perforation pattern comprises decreasing size of perforations as exhaust flows laterally away from said inlet. 
     
     
         18 . (canceled) 
     
     
         19 . A method for optimizing exhaust flow distribution to an aftertreatment element in an exhaust aftertreatment device comprising a housing extending axially along an axis and having an upstream inlet for receiving exhaust and having a downstream outlet for discharging exhaust, said inlet being a side inlet receiving exhaust flowing laterally into said housing relative to said axis, and an aftertreatment element in said housing passing exhaust axially therethrough then to said outlet, said method comprising providing a diffuser tube extending downstream laterally away from said inlet, providing said diffuser tube with a variable perforation pattern providing a diffuser outlet flow area which decreases as exhaust flows laterally away from said inlet, said method further comprising optimizing even exhaust flow distribution by decreasing at least one of density and size of perforations of said variable perforation pattern as said diffuser tube extends laterally away from said inlet to optimize and achieve even flow distribution of exhaust flowing axially to said aftertreatment element.