Exhaust gas aftertreatment system

An exhaust gas aftertreatment system comprising:

• a housing assembly comprising:
• a catalyst member housing configured to receive exhaust gas, and
• a flow divider comprising:
• a first endcap having apertures, and
• a second endcap having apertures;
• a first catalyst member extending within the catalyst member housing and configured to receive, treat, and output a first portion of the exhaust gas;
• and
• a second catalyst member extending within the catalyst member housing and configured to receive, treat, and output a second portion of the exhaust gas;
• wherein:
• a total area of all apertures of the first endcap is greater than a total area of all apertures of the second endcap;
• the first endcap is positioned over a portion of the first catalyst member;
• and
• the second endcap is positioned over a portion of the second catalyst member.

An exhaust gas aftertreatment system comprising:

• a housing assembly comprising:
• a catalyst member housing configured to receive exhaust gas and centered on a catalyst member housing axis, and
• a flow divider comprising:
• a first endcap having a plurality of first apertures, which are all of the apertures of the first endcap and define a first total area, and
• a second endcap having a plurality of second apertures, which are all of the apertures of the second endcap and define a second total area different from the first total area;
• a first catalyst member extending within the catalyst member housing and configured to receive, treat, and output a first portion of the exhaust gas, the first catalyst member comprising:
• a first catalyst member inlet that is disposed along a catalyst member inlet plane, the catalyst member inlet plane being orthogonal to the catalyst member housing axis, and
• a first catalyst member outlet that is disposed along a first catalyst member outlet plane, the first catalyst member outlet plane being orthogonal to the catalyst member housing axis, the first catalyst member outlet plane separated from the catalyst member inlet plane by a first catalyst member separation length;
• and
• a second catalyst member extending within the catalyst member housing and configured to receive, treat, and output a second portion of the exhaust gas, the second catalyst member comprising:
• a second catalyst member inlet that is disposed along the catalyst member inlet plane, and
• a second catalyst member outlet that is disposed along a second catalyst member outlet plane, the second catalyst member outlet plane being orthogonal to the catalyst member housing axis, the second catalyst member outlet plane separated from the catalyst member inlet plane by a second catalyst member separation length, the second catalyst member separation length being equal to between 95% of the first catalyst member separation length and 105% of the first catalyst member separation length, inclusive;
• wherein the first endcap is positioned over a portion of the first catalyst member;
• and
• wherein the second endcap is positioned over a portion of the second catalyst member.