An array includes a plurality of refractory bricks, each having a substantially tubular body including a first end, an opposed second end, a central bore extending from the first end to the second end along the longitudinal length thereof and defining an inner surface of the refractory brick, and an outer surface extending from the first end to the second end along the longitudinal length thereof. The outer surface of each refractory brick has a shape that transitions axially between a plurality of hexagonal portions and non-hexagonal portions along the longitudinal lengths thereof, and the plurality of refractory bricks are arranged and interlocked with one another in a vertical and horizontal manner via mating members provided on the hexagonal portions of the outer surfaces thereof. A continuous plenum space is defined by the non-hexagonal portions of the refractory bricks arranged in the array.