Pipe & Insulation Parameters
Heat Loss / Gain Results
Bare Pipe Heat Loss
—
BTU/hr
Insulated Heat Loss
—
BTU/hr
Heat Loss Reduction
—
%
Insulated Loss per ft
—
BTU/hr per ft
Energy Cost & Condensation Analysis
| Insulation Thickness | Heat Loss (BTU/hr) | % Reduction | Est. Annual Cost |
|---|
Cylindrical heat loss: q = |Tf − Ta| / (R_ins + R_out), where R_ins = ln(r2/r1)/(2πkL) and R_out = 1/(h·2πr2·L). r1 = pipe OD/2, r2 = r1 + insulation thickness (ft). Bare pipe: R_out only at pipe surface. h = 1.5 BTU/hr·ft²·°F (still air). Critical radius r_crit = k/h; for very small pipes with thin insulation, q may increase until r2 > r_crit (this is physically correct, not a calculation error). Dew point from Magnus formula. Annual cost assumes 8,760 hr/yr.