### Heat Loss Calculation for a Flat-Plate Solar CollectorConsider a flat-plate solar collector placed horizontally on the flat roof of a house. The collector dimensions are as follows:- **Width**: 5 ft- **Length**: 15 ftThe average temperature of the exposed surface of the collector is **94°F**. The emissivity of the exposed surface of the collector is **0.9**. #### Objective:Determine the rate of heat loss from the collector by convection and radiation on a calm day when the ambient air temperature is **70°F** and the effective sky temperature for radiation exchange is **50°F**. Take the convection heat transfer coefficient on the exposed surface as **2.5 Btu/h·ft²·°F**.#### Given:- \(\sigma = 0.1714 \times 10^{-8} \text{ Btu/h·ft²·R}^4\)- Solar collector surface temperature, \(T_s = 94°F\)- Ambient air temperature, \(T_{air} = 70°F\)- Effective sky temperature, \(T_{sky} = 50°F\)- Convection heat transfer coefficient, \(h = 2.5 \text{ Btu/h·ft²·°F}\)- Emissivity, \(\varepsilon = 0.9\)#### Calculation of Heat Loss:Using the given data, the total heat loss from the collector can be broken down into:1. **Convective Heat Loss**: \[ Q_{conv} = h \cdot A \cdot (T_s - T_{air}) \]2. **Radiative Heat Loss**: \[ Q_{rad} = \varepsilon \cdot \sigma \cdot A \cdot (T_s^4 - T_{sky}^4) \]where:- \(A\) is the area of the solar collector.- \(T_s, T_{air}, T_{sky}\) are the temperatures in Rankine (°R), where \(°R = °F + 459.67\).Given the area \(A = 5 \times 15 = 75 \text{ ft}^2\):- \(T_s = 94 + 459.67\)- \(T_{air} = 70 + 459.67\

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Consider a flat-plate solar collector placed horizontally on the flat roof of a house. The collector is 5 ft wide and 15 ft long, and the average temperature of the exposed surface of the collector is 94°F. The emissivity of the exposed surface of the collector is 0.9. Determine the rate of heat loss from the collector by convection and radiation on a calm day when the ambient air temperature is 70 °F and the effective sky temperature for radiation exchange is 50°F. Take the convection heat transfer coefficient on the exposed surface as 2.5 Btu/h-ft2. F.

Consider a flat-plate solar collector placed horizontally on the flat roof of a house. The collector is 5 ft wide and 15 ft long, and the average temperature of the exposed surface of the collector is 94°F. The emissivity of the exposed surface of the collector is 0.9. Determine the rate of heat loss from the collector by convection and radiation on a calm day when the ambient air temperature is 70 °F and the effective sky temperature for radiation exchange is 50°F. Take the convection heat transfer coefficient on the exposed surface as 2.5 Btu/h-ft2. F.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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