Figure 7
The illustration presents four sections: two diagrams (a and b) and two photos (c and d), arranged in a 2 by 2 grid. Section “a,” located at the top-left, is a schematic diagram of an “Existing furnace wall (3 meters by 3 meters).” It's a square grid showing nine square openings. The top row of openings is labeled “50 percent,” “40 percent,” and “30 percent” from left to right. The middle row is labeled “20 percent,” “10 percent,” and “05 percent.” The bottom row has two openings marked with an “X,” and the last opening is labeled “Control.” An arrow, labeled “60 centimeters by 60 centimeters openings,” from the top points downward to the “50 percent” opening. Section “b,” positioned at the top-right, is a detailed zoomed-in diagram of one “60 centimeters cross 60 centimeters opening” from section “a,” specifically the “05 percent” opening, as indicated by a dashed line connection from “a” to “b.” This diagram shows a brickwork pattern with “10 millimeters joint” indicated at the top. It illustrates the placement of bricks and mortar joints. Within two specific bricks, marked “Brick Roman numeral 1 (6 T C s)” and “Brick Roman numeral 2 (6 T C s),” the positions of thermocouples (T C s) are indicated, labeled “T C 1, T C 2, T C 3, T C 4, T C 5, T C 6.” Dimensions are provided: “48.8 centimeters” for height and “57.5 centimeters” for width, enclosing the brick pattern. Section “c,” located at the bottom-left, is a photo showing a section of a furnace wall with multiple rectangular openings, corresponding to the layout shown in “a.” Some openings have covers with numbers written on them (“C R 50,” “C R 40,” “C R 30,” “C R 20,” “C R 10,” “C R 05,” and “C R 00”). Wires from thermocouples, are visible extending from some of these covers. The wall appears to be made of brick. Secton “d,” at the bottom-right, is another photo of the same furnace wall section as in “c,” but the labels reads as follows: “R 8 50,” “R 8 40,” “R 8 30,” “R 8 20,” “R 8 10,” “R 8 05,” and “R 8 00.”A schematic diagram and test setup of (a) furnace layout and (b) thermocouples positions, (c) CR-based wall, and (d) R8-based wall, with photos showing the unexposed faces. Authors’ own work