Solar Energy and the Sun
Dive into the fascinating world of solar energy and the Sun's role in providing us with solar radiation. Learn about the solar constant, extraterrestrial radiation variations, and the intricate layers of the Sun, from its core to the photosphere and beyond.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
Solar Thermal Energy Solar Thermal Energy
1 1- - Solar Radiation Solar Radiation
The Sun 9 A sphere of hot gases. 1.39 x10 m Dia that have 3 zones: - Core: 0.23 R - T = 8 40 M K - (Nuclear fusion reactor) - Transition: 0.7 R (from core to conv. Zone) - Convection zone: - T = 130,000 K down to 5000 K - The outer shell of the convective zone is called the Photosphere - which is the source of most solar radiation Note: - Outside of the photosphere there are 3 layers: - Reversing layer cooler than photosphere - Chromosphere T starts to increase above 5000 K - Corona T up to 5 000,000 K - Yet we are not affected by this temp, since those layers are of very low density
THE SOLAR CONSTANT THE SOLAR CONSTANT
Solar Constant Definition: The solar constant Gsc is the energy from the sun per unit time received on a unit area of surface perpendicular to the direction of propagation of the radiation at mean earth- sun distance outside the atmosphere. WRC adopted value of 1367 W/m 2
VARIATION OF EXTRATERRESTRIAL RADIATION VARIATION OF EXTRATERRESTRIAL RADIATION Variation of the earth-sun distance, however, does lead to variation of extraterrestrial radiation flux in the range of 3.3%. The dependence of extraterrestrial radiation on time of year is shown in Figure 1.4.1. A simple equation with accuracy adequate for most engineering calculations is given by Equation 1.4.1a. Spencer (1971), as cited by Iqbal (1983), provides a more accurate equation ( 0.01%) in the form of Equation 1.4.1b:
