Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Inside Square Meter Kelvin Per Watt (m²K/W)

Required number input.

Wall Square Meter Kelvin Per Watt (m²K/W)

Required number input.

Outside Square Meter Kelvin Per Watt (m²K/W)

Required number input.

Area-based overall heat-transfer coefficient from three supplied thermal resistances per unit area in series. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Overall Watts Per Square Meter Kelvin (W/(m²·K))

The resulting overall watts per square meter kelvin returned as a number.

• Heat-transfer estimates depend on geometry, contact resistances, radiation, convection regime, temperature-dependent properties, fouling, phase change, and boundary conditions. Tabulated coefficients and COP values are operating-condition specific.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Heat Exchanger LMTD Method

  Steady heat-exchanger duty Q=U A ΔTlm for a supplied overall coefficient, reference area and already-corrected LMTD.

• Composite Wall Thermal Resistance

  Area-normalized thermal resistance of two plane solid layers in series, d1/k1+d2/k2; excludes film resistances.

• Convective Heat Transfer

  Newton-law convection heat-transfer rate hAΔT with a supplied convection coefficient at the stated flow condition.