A spherical interplanetary probe with 30-cm diameter contains electronic equipment that dissipates 100 W. If the probe surface has emissivity of 0.8, what is its surface temperature in outer space? State your assumptions in calculation.
GIVEN Interplanetary probe with 30-cm diameter, radius(r) =0.15 m Dissipation qr=100 W and emissivity (?)=0.8
• FIND
Surface temperature in outer space.
ASSUMPTIONS
• Steady state condition.
• Heat transfer only by radiation.
• Temperatue of outer space is considered 0 Kelvin. (T2)=0 K
PROPERTIES AND CONSTANTS
The Stefan-Boltzmann constant (?) = 5.67 × 10–8 W/(m2 K4)
The rate of radiation from a body,
Thus surface temperature of probe in outer space is 297 K.
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