Convert Square inches per minute to Square millimetres per hour

Convert Square inches per minute (in²/min) to Square millimetres per hour (mm²/h) instantly and accurately.

Square inches per minute (in²/min)
Square millimetres per hour (mm²/h)

Conversion Formula

mm²/h = in²/min × 38709.6

About Square inches per minute

The square inch per minute (in²/min) equals ≈1.075 × 10⁻⁵ m²/s, found in US military and aerospace specifications for thermal protection materials and ablative heat shields. Some NASA technical reports on reentry vehicle TPS (Thermal Protection System) materials quote diffusivity in in²/min. 1 in²/min = 0.00064516/60 m²/s.

About Square millimetres per hour

The square millimetre per hour (mm²/h) equals 1/3 600 000 000 m²/s, the smallest practical thermal diffusivity unit. It is used in very slow heat-transfer processes such as diffusion through frozen soils or phase-change materials studied over many hours. Heavy clay soils can show diffusivity values of 1-2 mm²/h. 1 mm²/h = 1e-6/3600 m²/s.

Quick Reference Table

Square inches per minute (in²/min)Square millimetres per hour (mm²/h)
1 in²/min38709.6 mm²/h
2 in²/min77419.2 mm²/h
5 in²/min193548 mm²/h
10 in²/min387096 mm²/h
25 in²/min967740 mm²/h
50 in²/min1935480 mm²/h
100 in²/min3870960 mm²/h

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