Mixer for exhaust aftertreatment system

Abstract

A flow device for a mixer of an exhaust aftertreatment system. The flow device includes a plate and a plurality of conduits coupled to the plate. Each of the conduits includes a first sidewall extending outward of the plate, a second sidewall extending outward of the plate and opposing the first sidewall, a main wall extending from the plate and between the first sidewall and the second sidewall, a conduit inlet coplanar with the plate and that receives exhaust, and a conduit outlet forming an angle between 35 degrees and 145 degrees, inclusive, with the plate. The conduit outlet releases the exhaust received from the conduit inlet.

What is claimed is: 
     
         1 . A flow device for a mixer of an exhaust aftertreatment system, the flow device comprising:
 a plate, and   a plurality of conduits coupled to the plate, each of the conduits comprising:
 a first sidewall extending outward of the plate, 
 a second sidewall extending outward of the plate and opposing the first sidewall, 
 a main wall extending from the plate and between the first sidewall and the second sidewall, 
 a conduit inlet coplanar with the plate and configured to receive exhaust, and 
 a conduit outlet forming an angle between 35 degrees and 145 degrees, inclusive, with the plate, the conduit outlet configured to release the exhaust received from the conduit inlet. 
   
     
     
         2 . The flow device of  claim 1 , wherein:
 the plate has a plate radius;   a first conduit radius is defined between a center of the plate and the first sidewall of one of the conduits;   a second conduit radius is defined between the center of the plate and the second sidewall of the one of the conduits;   a ratio of the first conduit radius to the plate radius is between 0.2 and 0.3, inclusive; and   a ratio of the second conduit radius to the plate radius is between 0.8 and 0.9, inclusive.   
     
     
         3 . The flow device of  claim 1 , wherein the main wall comprises a curved portion extending from the plate and a flat portion extending from the curved portion, the flat portion being parallel to the plate. 
     
     
         4 . The flow device of  claim 3 , wherein a section of the flat portion overlaps a section of the plate. 
     
     
         5 . The flow device of  claim 1 , wherein the main wall comprises a first portion orthogonal to the plate. 
     
     
         6 . The flow device of  claim 5 , wherein the main wall further comprises a second portion orthogonal to the first portion. 
     
     
         7 . The flow device of  claim 5 , wherein the main wall further comprises a second portion extending from the first portion at a non-zero angle relative to the plate. 
     
     
         8 . The flow device of  claim 1 , wherein:
 the conduit outlet of at least one of the conduits has a length and a height; and   a ratio of the length to the height is between 1.5 and 5, inclusive.   
     
     
         9 . The flow device of  claim 1 , wherein the conduits are contained within a sector of the plate, the sector having an angle span between 160 degrees and 225 degrees, inclusive. 
     
     
         10 . The flow device of  claim 1 , wherein:
 the plate comprises an aperture disposed away from the conduits, the aperture defines a first open area on the plate;   the conduit outlet defines a second open area; and   the second open area is equal to 35% to 150%, inclusive, of the first open area.   
     
     
         11 . The flow device of  claim 10 , wherein the aperture is disposed between two adjacent conduits of the conduits. 
     
     
         12 . The flow device of  claim 1 , wherein:
 the conduit inlet defines a conduit inlet open area;   the conduit outlet defines a conduit outlet open area; and   a ratio of the conduit outlet open area to the conduit inlet open area is between 0.5 and 2, inclusive.   
     
     
         13 . The flow device of  claim 12 , wherein the ratio of the conduit outlet open area to the conduit inlet open area is between 0.5 and 2.0, inclusive. 
     
     
         14 . A mixer for an exhaust aftertreatment system, the mixer comprising:
 an inlet configured to receive exhaust from an exhaust conduit;   an outlet configured to provide a mixture of the exhaust and a treatment fluid;   a first flow device configured to receive the exhaust from the inlet, the first flow device comprising:
 a plurality of main vanes, and 
 a plurality of main vane apertures interspaced between the main vanes, each of the main vane apertures configured to receive the exhaust and to cooperate with at least one of the main vanes to facilitate swirling of the exhaust; and 
   the flow device of  claim 1 , wherein the flow device is a second flow device disposed downstream of the first flow device and configured to receive the exhaust from the first flow device.   
     
     
         15 . An aftertreatment system comprising:
 the mixer of claim  14 ; and   an injector of a dosing module, wherein:
 the first flow device is disposed upstream of the injector, and 
 the second flow device is disposed downstream of the injector. 
   
     
     
         16 . The mixer of  claim 14 , further comprising a third flow device disposed downstream of the second flow device and configured to receive the exhaust and the treatment fluid from the second flow device, the third flow device comprising a plurality of peripheral apertures and a main aperture, wherein a distance between a center of the third flow device and each of the peripheral apertures is 90% to 98%, inclusive, of a radius of the third flow device. 
     
     
         17 . The mixer of  claim 16 , wherein:
 an eccentricity of the main aperture is between 0 and 0.5, inclusive;   the main aperture overlaps at least a portion of at least one conduit of the conduits; and   a ratio of a hydraulic radius of the main aperture to a hydraulic radius of the third flow device is between 0.4 and 0.7, inclusive.   
     
     
         18 . The mixer of  claim 16 , wherein the third flow device further comprises a plurality of auxiliary apertures located between the peripheral apertures and the main aperture, the auxiliary apertures overlap a region of the second flow device that does not include the conduits. 
     
     
         19 . A mixer for an exhaust aftertreatment system, the mixer comprising:
 an inlet configured to receive exhaust from an exhaust conduit;   an outlet configured to provide a mixture of the exhaust and a treatment fluid;   a first flow device configured to receive the exhaust from the inlet, the first flow device comprising:
 a plurality of main vanes, and 
 a plurality of main vane apertures interspaced between the main vanes, each of the main vane apertures configured to receive the exhaust and to cooperate with at least one of the main vanes to facilitate swirling of the exhaust; 
   a second flow device disposed downstream of the first flow device and configured to receive the exhaust from the first flow device, the second flow device comprising:
 a plate, and 
 a plurality of conduits coupled to the plate, each of the conduits comprising:
 a first sidewall extending outward of the plate, 
 a second sidewall extending outward of the plate and opposing the first sidewall, 
 a main wall extending from the plate between the first sidewall and the second sidewall, 
 a conduit inlet coplanar with the plate and configured to receive the exhaust, and 
 a conduit outlet forming an angle between 35 degrees and 145 degrees, inclusive, with the plate, the conduit outlet configured to release the exhaust received from the conduit inlet; 
 
 wherein the conduit outlet of at least one of the conduits has a length and a height, and a ratio of the length to the height is between 1.5 and 5, inclusive; and 
   a third flow device disposed downstream of the second flow device and configured to receive the exhaust and the treatment fluid from the second flow device, the third flow device comprising a plurality of peripheral apertures and a main aperture, wherein a distance between a center of the third flow device and each of the peripheral apertures is 90% to 98%, inclusive, of a radius of the third flow device.   
     
     
         20 . An aftertreatment system comprising:
 the mixer of claim  19 ; and   an injector of a dosing module, wherein:
 the first flow device is disposed upstream of the injector, and 
 the second flow device is disposed downstream of the injector.