ABE-TSM436_Lecture4 - Solar Radiation What is the maximum...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
2/1/2010 1 Solar Radiation Solar Radiation What is the maximum solar radiation beyond the earth’s atmosphere? How much solar radiation available in the west wall of Agricultural Engineering Building at 3pm, March 30? θ surface sun’s rays
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/1/2010 2 Topics of the Day * Solar spectrum * Mean solar constant * ASHRAE clear sky model * National solar radiation data base * Collector orientation
Background image of page 2
2/1/2010 3 Solar Spectrum ¾ Sun’s surface temperature: 5,500 – 6,000 ° C (9,940 – 11,000 ° F) ¾ Electromagnetic radiation (0.1 μ m – 100 m) ¾ Ultraviolet: 0.29 – 0.40 μ m, 9% ¾ Visible: 0.40 – 0.70 μ m, 40% ¾ Infrared: 0.70 – 3.50 μ m, 51% ¾ Peak at 0.48 μ m (green) m T μ λ 6 . 5215 max = T = absolute temperature, Rankine T (R) = t (F) + 459.67
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/1/2010 4 Spectral Distribution of Solar Radiation m m - air mass air mass w = 30 w = 30 30 mm 30 mm precipitable precipitable water water d = 400 d = 400 400 particles per 400 particles per cubic centimeter cubic centimeter (McQuiston et al., 2005)
Background image of page 4
2/1/2010 5 Air Mass Ratio m ¾ Air mass ratio is a measure of the amount of atmosphere the sun’s rays must pass through to reach the earth’s surface. (McQuiston et al., 2005)
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
6 Mean Solar Constant Mean Solar Constant is the rate of radiation on the surface normal to the sun’s rays beyond the earth’s atmosphere and at the mean earth-sun distance. G sc = 1366 w/m 2 Then, how to calculate the total radiation G t ? ASHRAE clear sky model.
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/30/2011 for the course TSM 436 taught by Professor Wang,x during the Spring '08 term at University of Illinois, Urbana Champaign.

Page1 / 24

ABE-TSM436_Lecture4 - Solar Radiation What is the maximum...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online