What is being measured?
Thermal diffusivity describes heat diffusion in a stated material model. Its squared-length-per-time dimensions do not make it kinematic viscosity.
Thermal diffusivity has the same dimensions as kinematic viscosity but describes heat diffusion rather than fluid momentum diffusion.
Meaning of mm²/s
Square millimeters per second uses the symbol mm²/s in this library and measures thermal diffusivity. Under the stated reference convention, 1 mm²/s = approximately 0.000001 m²/s. This equivalence changes how a known value is written. It does not increase measurement accuracy or establish whether a measurement is appropriate to a real application.
Conversion method
Multiply the value by the source factor (0.000001), then divide by the target factor (1). The factor ratio expresses the same thermal diffusivity measurement in the other unit.
Worked example
For a known value of 10 mm²/s, the reference conversion gives 0.00001 m²/s. Converting that result back gives approximately 10 mm²/s. This reverse check helps catch a reversed factor, but matching round-trip arithmetic alone does not independently verify a source definition.
Common reference values
| Input (mm²/s) | Reference equivalent (m²/s) |
|---|---|
| 1 | 0.000001 |
| 5 | 0.000005 |
| 10 | 0.00001 |
| 25 | 0.000025 |
| 50 | 0.00005 |
| 100 | 0.0001 |
Compare one mm²/s with other units
| Target unit | Equivalent of 1 mm²/s | Definition guide |
|---|---|---|
| Square meters per second (m²/s) | 0.000001 | Read definition |
| Square centimeters per second (cm²/s) | 0.01 | Read definition |
| Square feet per hour (ft²/h) | 0.0387500775002 | Read definition |
Precision and common mistakes
- Keep the source and target quantity consistent. A matching symbol is not enough to establish a compatible definition.
- Record the original measurement precision. Showing twelve significant digits in a table does not make a rounded input more precise.
- Check symbol capitalization, prefixes and any regional convention in the source. Use the displayed unit definition rather than a similarly named unit.
- Factors involving repeating fractions or π use finite numerical precision. Round the final answer to the precision justified by your input.
Use a working converter
- Thermal diffusivity converter
- Square millimeters per second to Square meters per second converter (thermal diffusivity)
- Square millimeters per second to Square centimeters per second converter (thermal diffusivity)
- Square millimeters per second to Square feet per hour converter (thermal diffusivity)
Source and verification scope
Examples and tables are computed from the versioned unit definitions used by the linked converters. The source access dates appear below. Computandum is independent of the cited organizations; a citation does not mean that a publisher endorses this page or an actual project.