Post by jliebler on Mar 17, 2021 15:55:07 GMT -8
I have a design problem with making the bell out of all firebrick, the ISA comes out 16+ M square even after making the bell top of ceramic fiber board. My thoughts are insert a course of insulated fire brick just below the oven this would put about 4.5 square meters in the oven region, then insulate outside this portion. AND add a bypass. My idea is a fixed small opening, right at the top of the bell, into the flue that is inside the bell but wrapped with superwool. The flue is 7" is square for a flow area of about 38 square inches and is 6 3/4" above the floor centered along one wall so flow into the bottom is fairly unrestricted. My chimney above the bell will be another 15 feet of 7 inch round well insulated. The idea is the hot gas injected will expand and rise pulling the colder gas below up the chimney even if the cold gas is right at room temperature. My WAG is a 1" diameter hole is all it takes. For good measure I'll not insulate the top segment of flue liner so it'll add heat to the flue gases. I'll attach the sketch up if I can get it down to 1 meg.
Darn got the file size down to 681 k by deleting unused stuff from earlier work but the forum is over it's limit.
Darn got the file size down to 681 k by deleting unused stuff from earlier work but the forum is over it's limit.