Problem regarding the electrical resistance elements

Reference no: EM131019897

Consider a plate that is well insulated on its back side and maintained at 200°C by imbedded electrical resistance elements. The exposed surface has an emissive power of 1200 W/m2, irradiation of 2500 W/m2, and reflectivity of 30%. The exposed surface experiences air flow having a free stream temperature of 20°C with a convection coefficient of 15 W/m2

(a) What is the radiosity, J?

(b) Determine the net radiation heat flux leaving the surface,q" _{rad net} , in terms of the radiosity and irradiation.

(c) Determine the combined convection and net radiation heat flux leaving the surface.

(d) Represent a surface energy balance schematically, and label all the radiation processes.

(e) What is the electrical power requirement, P" _e (W/m2), to maintain the plate under these conditions?

Reference no: EM131019897

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