SOLVE - heat transfer - Measurement of Emissivity

To determine the emissivity of a gray surface using emmisivity measurement apparatus.

Set voltage

5V

10V

15V

Q (w) 10

T₁ (°C) 10

T₂ (°C) 10

T₃ (°C) 10

T₄ (°C) 10

T₅(°C) 10

$$T_b = \frac{T_1 + T_2}{2}K$$

$$T_g = (T_3 + T_4)K$$

$$T_a = T_5K$$

Emissivity of test slab

$$∈ = \frac{T_b^4 - T_a^4}{T_g^4 - T_a^4}$$

$$∈ =$$

Emissivity of Surface