Emissivity in aircraft design refers to a material’s ability to emit thermal radiation compared to an ideal blackbody (a perfect emitter and absorber of thermal radiation). It’s an important factor to consider when designing aircraft components that operate at high temperatures, as it affects their ability to dissipate heat.The formula for emissivity (ε) is defined as:
- Emissivity is a dimensionless quantity and ranges from 0 to 1:
- ε = 0 indicates a perfectly reflective surface that doesn’t emit thermal radiation.
- ε = 1 indicates a perfect blackbody that emits thermal radiation as efficiently as possible at a given temperature.