Exhaust flow modifier, duct intersection incorporating the same, and methods therefor

A method of improving gas flow in an exhaust system, the method comprising:

• determining a location within a duct intersection having undesirable flow characteristics, wherein the duct intersection includes (i) a first duct portion having a first wall and configured to direct a gas in a first direction, and (ii) a second duct portion having a second wall angled relative to the first wall and configured to direct a gas in a second direction angled relative to the first direction, the first duct portion having a selectively openable end portion that (i) in normal operation, is closed such that gas flow of the exhaust system is through the second duct portion, and (ii) opens based on 4 pressure of the gas;
• and
• providing a flow modifier in the duct intersection at the determined location, the flow modifier being anchored in a fixed position to a portion of the first wall and a portion of the second wall, such that fluid is inhibited from flowing between the flow modifier and both the portion of the first wall and the portion of the second wall, the flow modifier comprising a contoured duct liner including an outermost surface configured to modify the direction of gas flow at the determined location.