🧱 Thermal Insulation Thickness Optimizer
Compute the required pipe insulation thickness to meet a heat-loss target, surface-temperature limit, or minimize total annual cost (economic thickness). Supports fiberglass, mineral wool, calcium silicate, PU foam, and elastomeric insulation.
📝 Configuration
q = (T_p−T_a) / [ln(r₂/r₁)/(2πk) + 1/(2πr₂h)]
T_s = T_a + q/(2πr₂h)
r_cr = k/h (critical radius)
Economic: min(energy + insulation cost)
📊 Results
Configure inputs and click Optimize to view results.
📘 Methodology
Radial Conduction
Heat transfer through cylindrical insulation uses the radial conduction equation with logarithmic thermal resistance R_ins = ln(r₂/r₁)/(2πk) and external convection R_conv = 1/(2πr₂h). The total heat loss per unit length is q = ΔT/(R_ins + R_conv).
Critical Radius
The critical radius r_cr = k/h is the outer radius at which adding insulation actually increases heat loss (reducing convective resistance faster than adding conductive resistance). Below r_cr, thicker insulation increases heat loss — important for small wires with low-k insulation.
Economic Thickness
The economic optimum minimizes total annual cost = energy cost of heat loss + amortized insulation material cost. ASHRAE 90.1 provides prescriptive minimum thicknesses for energy conservation in buildings and industrial applications.