A flow shifter baffle (26, 210, 310) for mixing a fluid flow having at least two components, the flow shifter baffle comprising: a leading edge (212, 312) and a trailing edge (214, 314), the flow shifter baffle defining a transverse flow cross-section perpendicular to the fluid flow along an entire length between the leading and trailing edges, with the transverse flow cross-section having an outer periphery; a double divider wall element (216, 316) adjacent to the leading edge, the double divider wall element including first and second generally parallel walls (218, 220, 318, 320) and extending across the entire transverse flow cross-section and configured to divide the fluid flow into a central flow portion and first and second peripheral flow portions; a dividing panel (222, 322) adjacent to the trailing edge and coupled to the double divider wall element, the dividing panel including first and second sides (224, 226, 324, 326) facing opposite directions and being oriented transverse from the first and second generally parallel walls (218, 220, 318, 320);_and a plurality of occluding walls (228, 230, 232, 234, 328, 330, 332, 334) coupled to the double divider wall element and positioned to force movement of the first and second peripheral flow portions, wherein the central flow portion is delivered to the first and second side of the dividing panel, and wherein the plurality of occluding walls force the first peripheral flow portion to flow along the first side of the dividing panel and the second peripheral flow portion to flow along the second side of the dividing panel, thereby shifting the central flow portion towards an outer periphery of the flow shifter baffle as the first and second peripheral flow portions flow along the first and second sides of the dividing panel respectively. a leading edge (212, 312) and a trailing edge (214, 314), the flow shifter baffle defining a transverse flow cross-section perpendicular to the fluid flow along an entire length between the leading and trailing edges, with the transverse flow cross-section having an outer periphery; a double divider wall element (216, 316) adjacent to the leading edge, the double divider wall element including first and second generally parallel walls (218, 220, 318, 320) and extending across the entire transverse flow cross-section and configured to divide the fluid flow into a central flow portion and first and second peripheral flow portions; a dividing panel (222, 322) adjacent to the trailing edge and coupled to the double divider wall element, the dividing panel including first and second sides (224, 226, 324, 326) facing opposite directions and being oriented transverse from the first and second generally parallel walls (218, 220, 318, 320);_and a plurality of occluding walls (228, 230, 232, 234, 328, 330, 332, 334) coupled to the double divider wall element and positioned to force movement of the first and second peripheral flow portions, wherein the central flow portion is delivered to the first and second side of the dividing panel, and wherein the plurality of occluding walls force the first peripheral flow portion to flow along the first side of the dividing panel and the second peripheral flow portion to flow along the second side of the dividing panel, thereby shifting the central flow portion towards an outer periphery of the flow shifter baffle as the first and second peripheral flow portions flow along the first and second sides of the dividing panel respectively.