Convert Square millimetres per hour to Square inches per hour

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

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

Conversion Formula

in²/h = mm²/h × 0.0015500031

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.

About Square inches per hour

The square inch per hour (in²/h) equals ≈1.792 × 10⁻⁷ m²/s, used in US heat-transfer handbooks and HVAC insulation specifications. Pre-SI tables for building insulation board and refractory brick often list thermal diffusivity in in²/h. Firebrick: ≈3.5 in²/h; rigid foam: ≈0.8-1.2 in²/h. 1 in²/h = 0.00064516/3600 m²/s.

Quick Reference Table

Square millimetres per hour (mm²/h)Square inches per hour (in²/h)
1 mm²/h0.00155 in²/h
2 mm²/h0.00310001 in²/h
5 mm²/h0.00775002 in²/h
10 mm²/h0.0155 in²/h
25 mm²/h0.0387501 in²/h
50 mm²/h0.0775002 in²/h
100 mm²/h0.155 in²/h

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