Solar radiation is incident on a 5 m2 solar absorberplate surface at a rate of 800 W/m2. Ninety-three percent ofthe solar radiation is absorbed by the absorber plate, whilethe remaining 7 percent is reflected away. The solar absorberplate has a surface temperature of 40°C with an emissivityof 0.9 that experiences radiation exchange with the surroundingtemperature of -5°C. In addition, convective heat transferoccurs between the absorber plate surface and the ambientair of 20°C with a convection heat transfer coefficient of7 W/m2∙K. Determine the efficiency of the solar absorber,which is defined as the ratio of the usable heat collected bythe absorber to the incident solar radiation on the absorber.
Energy transfer
The flow of energy from one region to another region is referred to as energy transfer. Since energy is quantitative; it must be transferred to a body or a material to work or to heat the system.
Molar Specific Heat
Heat capacity is the amount of heat energy absorbed or released by a chemical substance per the change in temperature of that substance. The change in heat is also called enthalpy. The SI unit of heat capacity is Joules per Kelvin, which is (J K-1)
Thermal Properties of Matter
Thermal energy is described as one of the form of heat energy which flows from one body of higher temperature to the other with the lower temperature when these two bodies are placed in contact to each other. Heat is described as the form of energy which is transferred between the two systems or in between the systems and their surrounding by the virtue of difference in temperature. Calorimetry is that branch of science which helps in measuring the changes which are taking place in the heat energy of a given body.
Solar
plate surface at a rate of 800 W/m2. Ninety-three percent of
the solar radiation is absorbed by the absorber plate, while
the remaining 7 percent is reflected away. The solar absorber
plate has a surface temperature of 40°C with an emissivity
of 0.9 that experiences radiation exchange with the surrounding
temperature of -5°C. In addition, convective
occurs between the absorber plate surface and the ambient
air of 20°C with a
7 W/m2∙K. Determine the efficiency of the solar absorber,
which is defined as the ratio of the usable heat collected by
the absorber to the incident solar radiation on the absorber.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 3 images
