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Thermal engineering tools
Calculators & engineering references
Free, practical heat transfer calculations and technical references for engineering work.
Explore calculatorsHeat transfer
Temperature difference, heat duty, resistance and area.
HVAC & psychrometrics
Estimate moist-air properties from dry-bulb temperature, relative humidity and pressure.
Thermophysical properties
Explore liquid water and dry air properties at selected states.
Unit conversion
Convert lengths in metres, centimetres and inches.
Popular calculators
Log mean temperature difference
Calculate the LMTD for parallel or counterflow exchangers.
Sensible heat duty
Estimate heat duty using mass flow, specific heat and temperature.
Plane-wall conduction and resistance
Estimate steady heat transfer through single or multilayer plane walls.
Heat transfer area
Estimate area from duty, overall coefficient and temperature difference.
Moist air properties
Estimate humidity ratio, dew point, enthalpy and more.
ε-NTU exchanger effectiveness
Estimate single-pass exchanger effectiveness from NTU and capacity-rate ratio.
Straight fin efficiency
Estimate uniform straight-fin efficiency with an adiabatic tip.
Reynolds number
Calculate from density, speed, viscosity and hydraulic diameter.
Prandtl number
Calculate from specific heat, dynamic viscosity and fluid conductivity.
Nusselt number
Calculate from a known convection coefficient, characteristic length and fluid conductivity.
Psychrometric state chart
Plot relative-humidity curves and compare two states.
Adiabatic moist-air mixing
Estimate condensation-free adiabatic mixing of two moist-air streams.
Duct airflow and sensible heat
Estimate rectangular duct airflow and the sensible heat change of dry air.
Dittus–Boelter tube convection
Estimate fully developed single-phase turbulent convection in a smooth circular tube, within stated limits.
Moist air process enthalpy and water change
Calculate air-side changes from inlet and outlet enthalpy, humidity ratio and dry-air flow.
Phase-change latent heat rate
Calculate latent heat rate for isothermal evaporation or condensation.
Moist-air sensible and moisture enthalpy split
Split air-side enthalpy change along a chosen virtual path; not complete equipment duty.
Length conversion
Convert metres, centimetres and inches.
About thermalXsolver
A free bilingual engineering resource, built around clear inputs, units, calculation methods and applicability.
Results are engineering estimates. Review actual design conditions, reliable data and applicable standards.
Engineering references
Explore heat transfer, thermal resistance, properties and moist air, with links to related calculators.
Explore references →Single-phase water and superheated steam →
Discrete states at stated temperatures and absolute pressures; no interpolation.
Saturated water and steam transport and heat capacity →
Discrete saturated-liquid and dry-saturated-steam endpoints; no interpolation.
Water and dry-air property plots →
Discrete data points at 101.325 kPa absolute; no interpolation.
Heat stress, wet bulb and WBGT →
Learn the concepts and limits of occupational measurement.
Insulation and thermal resistance basics →
Explore the plane-wall model, material selection and condensation limits.
Heat exchanger engineering guide →
Explore heat balance, method selection and design checks.
Steam states and heat calculations →
Saturated water and steam table →
Listed discrete saturation states from 5–200 °C; no interpolation.
Spruce-shavings specimen conductivities →
Pipe-insulation specimen conductivities →
Authoritative material-conductivity sources →
Links to original sources, not a numerical property table hosted here.