Conduction Calculator

• •Use the Conduction Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations — instant feedback helps identify arithmetic errors before they propagate.
• •Use it during the early design phase to rapidly iterate on parameters and narrow down feasible configurations before committing time to detailed finite element simulations or full design packages.
• •Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility — a quick sanity check can prevent costly downstream errors.
• •Use it to generate reference data for a technical report or presentation without manual computation, ensuring consistent, reproducible numbers throughout the document.
• •Use it in the field when a quick estimate is needed and a full engineering software package is not available.

The Conduction Calculator is a precision engineering calculation tool designed for students, engineers, and technical professionals. Calculate heat conduction through flat walls, cylinders, and spheres with multi-layer flat wall support All calculations are performed using established engineering formulas from the relevant scientific literature and standards. Inputs support both metric (SI) and imperial unit systems, with unit conversion handled automatically — simply select your preferred unit from the dropdown next to each field. Results are computed instantly in the browser without sending data to a server, ensuring both speed and privacy. This calculator is intended as a supplementary tool for learning and design exploration; always verify results against authoritative references for safety-critical applications.

Heat conduction is the transfer of thermal energy through a material due to a temperature gradient, without bulk motion of the material. Fourier's law states that the heat flux is proportional to the temperature gradient: q = −k·dT/dx, where q is heat flux (W/m²), k is the thermal conductivity of the material (W/(m·K)), and dT/dx is the temperature gradient. The negative sign indicates heat flows from hot to cold. For a 1D steady-state flat wall with thickness L, face areas A, and temperatures T₁ and T₂, the heat transfer rate is Q = k·A·(T₁ − T₂)/L. For a cylindrical wall (pipe), Q = 2π·k·L·(T₁ − T₂)/ln(r₂/r₁), where r₁ and r₂ are inner and outer radii. For a spherical shell, Q = 4π·k·r₁·r₂·(T₁ − T₂)/(r₂ − r₁). Multi-layer walls are handled by summing thermal resistances in series: R_total = ΣR_i, where R_i = L_i/(k_i·A) for each layer. This is analogous to electrical resistance in series, with temperature difference as voltage and heat flow as current. Typical thermal conductivities (W/(m·K)): copper 400, aluminum 237, steel 50, stainless steel 16, concrete 1.4, brick 0.7, glass 0.8, water 0.6, insulation materials 0.02-0.04, wood 0.1-0.2, air (stationary) 0.025. Copper and aluminum are very good conductors; insulation materials (fiberglass, foam, aerogel) are very poor conductors. The thermal resistance concept (R = L/(k·A)) is the foundation of building envelope energy analysis and composite wall heat loss calculations. Actual heat transfer typically involves conduction through walls combined with convection on both sides, giving an overall heat transfer coefficient U = 1/(1/h₁ + L/k + 1/h₂) for a single-layer wall.

• •Building envelope heat loss: compute heat loss through walls, roofs, windows, and foundations using layered wall analysis. Each material layer contributes its thermal resistance; the total R-value determines the building's heating and cooling loads.
• •Pipe insulation design: determine the insulation thickness needed to limit heat loss from hot water, steam, or chilled water pipes. Cylindrical geometry is used because pipe walls are thin relative to insulation thickness.
• •Furnace and kiln wall design: high-temperature process equipment uses refractory bricks and insulation to contain heat and protect the outer shell. Multi-layer analysis sizes each layer for temperature limits and heat loss targets.
• •Heat sink for electronics: compute the conduction resistance through the base of a heat sink (from the chip surface to the fin base). This is one component of the total thermal resistance from chip to ambient.
• •Cold-storage insulation: walk-in freezers and refrigerators use thick insulation (6-12 inches of foam) to minimize heat gain. Thermal resistance analysis sizes the insulation for target energy performance.