20x20x.7854x48=15,000 cu. in.
15,000 cu. in. x 0.004 = 60 sq. in.
x 0.33 = 5,000 cu. in. FB
x 0.001 = 15 sq. in. FB air inlets...
15,000 x 0.022 = 330 cu. in.
exhaust stack
330 / .7854 x 4 x 4 = (26" stack) make it approx. 35" tall above the CC...
Using the circle calculator, the green area is the cut out for the FB/CC opening....
Chord AB is the width of the RF plate...
Segment Height ED is how tall the green area is.. 5"...
For calculating the FB/CC opening.... You are calculating for the GREEN area... that will be the cut-out area in the FB that mates to the CC....
The green area is a segment. It is called a "Segment Area"... That area is the same as the FB/CC opening....
When you open the "Circle Calculator" link, Click on the "bullet" to the left of Radius & Segment Height ED....
Circle Calculator
Click on the 2 variables you know
......Radius and Central Angle...........................Radius & Chord AB
[X] Radius & Segment Height ED.....................Radius & Apothem OE
......................................................Radius & Arc AB
......Chord AB & Segment Height ED................Chord AB & Apothem OE
......Segment Height ED & Apothem OE...........Chord AB & Arc AB
You should have opened the circle calculator and a bunch of boxes will appear below..
and a box called [CALCULATE]..
Enter the radius in the box so marked.... If you tank is 24" OD, and has a 3/8" thick steel wall, the ID of the tank 23.25".... the radius is 11.625"..... these numbers need to be accurate if you want stuff to fit... ALSO, take into account the thickness of the FB steel when cutting out the tank...
Enter a guess for the Segment Height ED... I'd start with 6.0
Click on [CALCULATE]....
The other boxes will fill with numbers....
The [Segment Area] box is what you area going to compare with the FB/CC opening in square inches...
If the FB/CC opening number is smaller, change the number in the Segment Height ED box to 5.... continue changing that number until the [Segment Area] matches the FB/CC number.....