Question
a.
In process heat exchangers, saturated steam is preferred over the superheated steam.
b.
The maximum is the emissive power of a surface at a temperature T1 occurs at a wavelength of λ1. If the surface temperature is halved, the maximum in the emissive power would occur at a wavelength of 0.5 λ1.
c.
When a vertical plate is heated in infinite air environmental under natural convection conditions, the velocity profile in air, normal to the plate, exhibits a maximum.
d.
A body at 925 K emits an energy of 1.42 x 10¹¹σW/m² (σ is the Stefan-Boltzman constant) in the wavelength band between 3 μm to 4 μm. The fraction of this energy in the total energy emitted over the entire wavelength range is equal to emissivity.
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