Reductant nozzle indentation mount

Abstract

An engine exhaust aftertreatment system including a bend routing an exhaust flow in a curved direction to a straight part. A nozzle is mounted in the bend to introduce a spray of a fluid with a axis of symmetry into the exhaust flow. The axis of symmetry intersects the exhaust flow traveling in the curved direction at a intersection angle of less than 50 degrees.

1 . An engine exhaust aftertreatment system comprising:
 a bend routing an exhaust flow in a curved direction;   a straight part receiving the exhaust flow from the bend; and   a nozzle mounted in the bend to introduce a spray of a fluid with a axis of symmetry into the exhaust flow wherein the axis of symmetry intersects the exhaust flow traveling in the curved direction at a intersection angle between the axis of symmetry and the exhaust flow of less than 50 degrees.   
     
     
         2 . The engine exhaust aftertreatment system of  claim 1  further including an indentation in the bend wherein the nozzle is mounted in the indentation. 
     
     
         3 . The engine exhaust aftertreatment system of  claim 2  wherein the indentation extends into more than 10% of a depth of the bend. 
     
     
         4 . The engine exhaust aftertreatment system of  claim 2  wherein the indentation includes an upstream wall with a upstream wall length of at least 10% of a depth of a bend inlet. 
     
     
         5 . The engine exhaust aftertreatment system of  claim 4  wherein the indentation includes a downstream wall with a downstream wall length of at least 10% of a depth of a bend outlet. 
     
     
         6 . The engine exhaust aftertreatment system of  claim 5  wherein the nozzle is mounted in the downstream wall. 
     
     
         7 . The engine exhaust aftertreatment system of  claim 6  wherein the nozzle is located to align the axis of symmetry of the spray with a central axis of the exhaust flow in the straight part. 
     
     
         8 . The engine exhaust aftertreatment system of  claim 6  wherein the upstream wall length is at least 50% of a depth of a bend inlet and the downstream wall length is at least 50% of a depth of a bend outlet. 
     
     
         9 . The engine exhaust aftertreatment system of  claim 1  wherein the indentation has a triangular shape. 
     
     
         10 . The engine exhaust aftertreatment system of  claim 1  wherein the intersection angle is less than 40 degrees. 
     
     
         11 . The engine exhaust aftertreatment system of  claim 1  wherein the intersection angle is approximately 30 degrees. 
     
     
         12 . The engine exhaust aftertreatment system of  claim 1  further including a selective catalytic reduction system and the fluid is a urea reductant. 
     
     
         13 . An engine exhaust aftertreatment system comprising:
 a bend routing an exhaust flow in a curved direction;   a straight part receiving the exhaust flow from the bend;   an indentation extending into more than 10% of a depth of the bend; and   a nozzle mounted in the indentation to introduce a spray of a fluid into the exhaust flow.   
     
     
         14 . The engine exhaust aftertreatment system of  claim 13  wherein the indentation includes an upstream wall with a upstream wall length of at least 10% of a depth of a bend inlet. 
     
     
         15 . The engine exhaust aftertreatment system of  claim 14  wherein the indentation includes a downstream wall with a downstream wall length of at least 10% of a depth of a bend outlet and the nozzle is mounted in the downstream wall. 
     
     
         16 . The engine exhaust aftertreatment system of  claim 13  wherein the indentation extends into more than 30% of a depth of the bend. 
     
     
         17 . The engine exhaust aftertreatment system of  claim 13  wherein the indentation extends into approximately 50% of a depth of the bend. 
     
     
         18 . An engine exhaust aftertreatment system comprising:
 a bend routing an exhaust flow in a curved direction;   a straight part receiving the exhaust flow from the bend;   an indentation including an upstream wall with a upstream wall length of at least 10% of a depth of a bend inlet; and   a nozzle mounted in the indentation to introduce a spray of a fluid into the exhaust flow   
     
     
         19 . The engine exhaust aftertreatment system of  claim 18  wherein the upstream wall length is at least 40% of a depth of a bend inlet. 
     
     
         20 . The engine exhaust aftertreatment system of  claim 18  wherein the upstream wall length is approximately 70% of a depth of a bend inlet.