Question

The walls and ceiling of a corridor are covered with glazed ceramic tile (emissivity = 0.6). The effluent from a nearby fire has heated the corridor surfaces to 400°C. Calculate the radiative flux incident on a person walking down this corridor. What is the likely impact of this thermal radiation on the person? If the air temperature is also 400°C, what is the impact of the convective heat on the person? Estimate the peak wavelength of the emitted energy.

a) Radiative flux provides warmth; Convective heat has a negligible effect
b) Radiative flux can cause burns; Convective heat adds to discomfort
c) Radiative flux has no impact; Convective heat is significant
d) Radiative flux and Convective heat both have negligible effects

Answer 1

The radiative flux incident on a person walking down the corridor can be calculated using the Stefan-Boltzmann law. The impact of the thermal radiation depends on the radiative flux, which can cause burns and discomfort if it is high enough. The peak wavelength of the emitted energy can be estimated using Wien's displacement law.

Step-by-step explanation:

To calculate the radiative flux incident on a person walking down the corridor, we can use the Stefan-Boltzmann law. The radiative flux is given by the equation F = sigma * emissivity * (T^4 - T_air^4), where F is the radiative flux, sigma is the Stefan-Boltzmann constant, emissivity is the emissivity of the ceramic tile, T is the temperature of the tile in Kelvin, and T_air is the air temperature in Kelvin.

The impact of this thermal radiation on the person depends on the radiative flux. If the radiative flux is high enough, it can cause burns and discomfort. On the other hand, if the radiative flux is low, the impact may be negligible.

The peak wavelength of the emitted energy can be estimated using Wien's displacement law. The peak wavelength is given by the equation lambda_max = b / T, where lambda_max is the peak wavelength, b is the Wien's displacement constant, and T is the temperature in Kelvin.