Surface Radiation Absorptivity
Absorptivity can be defined as
- the ratio of power absorbed to the incident radiant power
For emissivity and emitted light absorptivity is the amount of radiation absorbed by a surface compared to what is absorbed by a black body.
| Surface | Absorptivity |
|---|---|
| Aluminum, anodized | 0.14 |
| Aluminum, dull/rough polished | 0.4 - 0.65 |
| Aluminum. polished | 0.1 - 0.40 |
| Asbestos Cement, old | 0.83 |
| Black matte | 0.95 |
| Brick, red | 0.65 |
| Chromium plate | 0.20 |
| Concrete | 0.6 |
| Iron, galvanized old | 0.89 - 0.92 |
| Grey paint | 0.95 |
| Light green paint | 0.95 |
| Limestone | 0.33 - 0.53 |
| Red clay brick | 0.94 |
| Snow, ice granules | 0.33 |
| Steel, galvanized (zink oxide) | 0.65 |
| Steel, galvanized weathered | 0.8 |
| White paint | 0.25 - 0.4 |
Related Topics
• Thermodynamics
Work, heat and energy systems.
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