An infrared camera is used to measure a temperature at a tissue location. The infrared camera uses the same equation as that in the lecture notes. When the total hemispherical emissivity is selected as =1.0, the temperature reading on the camera is 45°C. (a) Based on the equation given in the notes, please calculate the radiation heat flux received by the camera qck. The Stefan-Boltzmann's constant ois 5.67* 108 W/(m² K¹). (b) However, you notice that the actual emissivity of the tissue surface should be 0.95. The room temperature is 20°C. Use the equation again to calculate the temperature of the tissue location, note that 9ck should be the same as in (a). What is the absolute error of the measurement if both the room temperature and deviation from a perfect blackbody surface are not considered?

An infrared camera is used to measure a temperature at a tissue location. The infrared camera uses the same equation as that in the lecture notes. When the total hemispherical emissivity is selected as =1.0, the temperature reading on the camera is 45°C. (a) Based on the equation given in the notes, please calculate the radiation heat flux received by the camera qck. The Stefan-Boltzmann's constant ois 5.67* 108 W/(m² K¹). (b) However, you notice that the actual emissivity of the tissue surface should be 0.95. The room temperature is 20°C. Use the equation again to calculate the temperature of the tissue location, note that 9ck should be the same as in (a). What is the absolute error of the measurement if both the room temperature and deviation from a perfect blackbody surface are not considered?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.22P

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Example What is the solar radiation on a horizontal surface in the absence of the atmosphere at latitude 36° N on November 9 between the hours of 10 and 11 AM?