Heat Flux Density Converter
Convert between 6 units of heat flux density — W/m², kW/m², W/cm², BTU/(h·ft²), cal/(s·cm²), and kcal/(h·m²).
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About the Heat Flux Density Converter
Heat flux density is the rate of heat energy transfer per unit area — how much thermal power flows through each square metre of a surface. The SI unit is W/m². It is critical in the design of heat exchangers, nuclear reactors, spacecraft thermal management, and electronic chip cooling. Solar irradiance at Earth's surface is a familiar example of heat flux: about 1,000 W/m² on a clear day.
Quick facts
- ›Solar irradiance at Earth's surface is approximately 1,000 W/m² on a clear summer day
- ›The heat flux from Earth's interior (geothermal) averages just 0.065 W/m²
- ›Modern CPU chips can generate heat fluxes exceeding 100 W/cm² (1,000,000 W/m²)
- ›The critical heat flux in nuclear reactors is carefully managed to prevent overheating
Common uses: Heat exchanger design, nuclear engineering, electronics cooling, solar energy, building physics