On baking industry sites, professional recipes [large quantity ingredients with commercial chemicals eg emulsifiers etc] indicate how many pounds of batter will be produced. These are then scaled into commercial pans. To replicate, you would have to have the ingredients, make that recipe and have those pans.
Conversely, you could try this method:
CALCULATING THE AMOUNT OF BATTER REQUIRED IN A DIFFERENT RECTANGULAR CAKE PAN THAN NORMALLY USED:
FOR EXAMPLE: You have a butter cake recipe that you usually cook in a 9x13x2 inch pan, and you want to cook that recipe in a larger pan.
1. Size of larger pan to be used: 11 inches wide, 17 inches long, 2 inches deep.
2. Size of pan being used: 9 inches wide, 13 inches long, 2 inches deep. Weigh the pan and record it's weight.
3. Make up your recipe and pour into pan. Weigh and record. The weight of the batter is that amount less the weight of the pan eg 34 ounces.
NOTE: you can do a lovely theoretical calculation by ingredient weights or just make and weigh [easier].
4. Calculate the volume of the 9x13x2 pan ie 9x13x2 = 234 cubic inches.
5. Calculate the volume which each ounce of batter occupies ie 234 cubic inches divided by 34 ounces = 6.75 cubic inches per ounce of batter.
6. Calculate the volume of the 11x17x2 pan ie 11x17x2= 374 cubic inches.
7. Divide that total volume by the amount of space occupied by 1 oz batter ie. 374 divided by 6.75 = 55 ounces of batter required for the the larger pan.
AMOUNT OF BATTER TO USE IN ROUND PAN:
FOR EXAMPLE: You have a butter cake recipe that you usually cook in a 9x13x2 inch pan, and you want to cook that recipe in a round pan. The previous calculation tells us that 1 oz cake batter occupies 6.75 cubic inches and the larger pan is 14 inches in diameter and 3 inches deep.
[Formula for volume is "pi" x radius squared x height.]
1. Radius of the pan equals half the diameter of the pan (14 divided by 2 = 7).
2. Radius squared is 7 inches x 7 inches = 49.
3. "pi" is approximately 3.14 - 3.14 x 49 = 154 .
4. Height of the pan is 3 inches
5. The volume of the 14 inch pan 3 inches deep is 3 x 154 = 462 cubic inches.
6. Divide the volume of the round pan by the previously calculated 6.75 cubic inches for an ounce of batter ie 462 divided by 6.75 = 68 ounces approximately for this 14 inch round pan [3 inches deep].
9X13X2 NEEDS 34 oz
11X17X2 NEEDS 55 oz
14" ROUND X 3" NEEDS 68 oz
Then you would have to scale your recipe up are down...........