Convert International table BTU per second per square foot to Watt per square metre
Convert International table BTU per second per square foot (BTU(IT)/(s·ft²)) to Watt per square metre (W/m²) instantly and accurately.
Conversion Formula
W/m² = BTU(IT)/(s·ft²) × 11356.52668
About International table BTU per second per square foot
The international table BTU per second per square foot (BTU(IT)/(s·ft²)) equals 1055.05585262/0.09290304 ≈ 11357 W/m² (= 3600 × BTU(IT)/(h·ft²)). Used for extreme heat flux: atmospheric re-entry aerodynamic heating, solid rocket nozzle throat, and nuclear reactor thermal hydraulics design. 1 BTU(IT)/(s·ft²) ≈ 11357 W/m².
About Watt per square metre
The watt per square metre (W/m²) is the SI coherent unit for heat flux density and irradiance. Solar irradiance at Earth's surface ≈ 1000 W/m²; solar constant ≈ 1361 W/m²; human skin radiative emission ≈ 100 W/m²; global average geothermal flux ≈ 0.087 W/m². Referenced in ISO 80000-4. 1 W/m² = 1 J/(s·m²) = 10⁻³ kW/m².
Quick Reference Table
| International table BTU per second per square foot (BTU(IT)/(s·ft²)) | Watt per square metre (W/m²) |
|---|---|
| 1 BTU(IT)/(s·ft²) | 11356.5 W/m² |
| 2 BTU(IT)/(s·ft²) | 22713.1 W/m² |
| 5 BTU(IT)/(s·ft²) | 56782.6 W/m² |
| 10 BTU(IT)/(s·ft²) | 113565 W/m² |
| 25 BTU(IT)/(s·ft²) | 283913 W/m² |
| 50 BTU(IT)/(s·ft²) | 567826 W/m² |
| 100 BTU(IT)/(s·ft²) | 1135650 W/m² |