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Radiation. Contributions by: Janet deGrazia Department of Chemical and Biological Engineering University of Colorado Boulder, CO 80309-0424.
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Radiation Contributions by: Janet deGrazia Department of Chemical and Biological EngineeringUniversity of ColoradoBoulder, CO 80309-0424
There is a long heated duct that has a semi-circle cross-sectional geometry. The view factor (F21) of the curved surface (2) to the flat surface (1) is_________. 0 0.36 0.5 0.64 1 2 1
There is a long heated duct that has a semi-circle cross-sectional geometry. The view factor (F12) of the flat surface (1) to the curved surface (2) is_________. 0 0.36 0.5 0.64 1 2 1
Two infinitely long parallel disks are in a vacuum. Disk 1 is a black body maintained at 25 °C. Disk 2 is diffuse and opaque and also maintained at 25 °C. The net radiation leaving disk 1 is _________ than that leaving disk 2. greater than less than the same as Not enough information Disk 1 Disk 2
Two infinitely long parallel disks are in a vacuum. Disk 1 is a black body maintained at 25 °C. Disk 2 is diffuse and opaque and also maintained at 25 °C. With respect to disk 1, the net radiation exchange between the disks is _________ zero. greater than less than equal to Not enough information Disk 1 Disk 2
A large hollow tube, S1, encloses a smaller solid tube, S2. Which statement is true? Both are at the same temperature and diffuse emitters. Which statement is true? The net radiation leaving S2 will be higher than that reabsorbed into S2. The view factor of S2 to itself will be greater than S1 to itself. The view factor of S1 to S2will be greater than S2to S1. All are true radiation S1 S2
Which of the following shows the spectral transmissivity for a semi-transparent diffuse material? A B
A B D C Which of the following shows the spectral transmissivity for an opaque diffuse material?