Question

The aluminum alloy (2024-t6) absorber plate is 6 mm thick and well insulated on its bottom. the top surface of the plate is separated from a transparent cover plate by an evacuated space. the tubes are spaced a distance / of 0.20 m from each other, and water is circulated through the tubes to remove the collected energy. the water may be assumed to be at a uniform temperature of 7z 60c. under steady-state operating conditions for which the qhw radiation heat flux to the surface is trad 800 w/m2 , what is the maximum temperature on the plate and the heat transfer rate per unit length of tube? note that trad represents the net effect of solar radiation absorption by the absorber plate and radiation exchange between the absorber and cover plates. you may assume the temperature of the absorber plate directly above a tube to be equal to that of the water.

Answer 1

The student query pertains to calculating the maximum temperature and heat transfer rate in a solar thermal system. Due to the absence of specific material properties and formulas, a numerical answer cannot be provided, but common heat transfer laws would be applied.

Step-by-step explanation:

The student is asking about the maximum temperature on a solar absorber plate and the heat transfer rate per unit length of tube in a solar thermal system. Given that the transparent cover plate is separated by an evacuated space, we can use the provided radiation heat flux (qrad) of 800 W/m2 to determine these values.

, without specific formulas or properties of the materials (like emissivity or absorptivity), we cannot provide a numerical answer. Common methods of determining the maximum temperature and heat transfer rate would include Fourier's law for conduction, Stefan-Boltzmann law for radiation, and possibly Newton's law of cooling for convective heat transfer between the fluid and the absorber plate.

Answer 2

The aluminum alloy(2024-T6; k=180 W/m!K,) absorber plate is 6 mm thick and well insulated on its bottom. The top surface of the plate is separated from a transparent cover plate by an evacuated space. The tubes arespaced a distance L of ...