Consider a 30-cm-diameter hemispherical enclosure. The dome is maintained at 600 K, and heat is supplied from the dome at a rate of 65 W while the base surface with an emissivity of 0.55 is maintained at 400 K. Determine the emissivity of the dome.

Explanation:

Diameter

Temperature

Rate of supply

Emissivity of base surface

Temperature at base

Generally the equation for Area of base surface is mathematically given by

Generally the equation for Area of Hemispherical dome is mathematically given by

Since base is a flat surface

Therefore

Generally the equation for Net rate of radiation heat transfer between two surfaces is mathematically given by

Where

Therefore

Therefore  the emissivity of the dome is

continuous conducting path for current, power supply