Post on 14-Apr-2017
Determination of
RADIATIONSOLAR
Byโข Ahmed Radwanโข Amr Mousaโข Hazem Hamdyโข Mostafa Elewa
๐ =2โ ๐๐ ๐ข๐๐ โ ๐๐ ๐ข๐๐ โ ๐ผ๐บ๐ ๐๐๐๐
2๐(๐๐ ๐๐ฆ4 + ๐๐ ๐ข๐๐
4 ) โ 2๐๐๐ ๐ข๐๐4
Final Idea (The solar energy incident )
MethodologyMathematical equations
๐๐๐ = ๐๐๐ข๐ก
๐ผ๐บ๐ ๐๐๐๐ + ๐๐๐๐ ๐๐ฆ4 + ๐๐๐๐ ๐ข๐๐
4 = 2๐๐๐๐ ๐ข๐๐4 + 2โ(๐๐ ๐ข๐๐ โ ๐๐ ๐ข๐๐)
h (heat conviction coefficient)
๐ ๐ =๐๐ฟ
๐ฃ=
5 โ 0.12
1.7 โ 10โ5= 35.25 โ 103
๐๐ข =โ๐ฟ
๐พ= 0.664 ๐ ๐ ๐๐ 1 3
Martial Parameters
๐ = 0.09 ๐๐๐ ๐ผ = 0.525
โข Commercial Aluminum
Tsky
๐๐ ๐๐ฆ =4 ิ๐ ๐๐๐๐
ิ๐ = 0.77 + 0.0038 ๐๐๐
The value of Tsky depends on the atmospheric conditions.
It ranges from about 230 K for cold, clear-sky conditions
to about 285 K for warm, cloudy-sky conditions.
MethodologyI. Hardware
Lm35 temperature sensors with Arduino.
MethodologyI. Hardware
MethodologyII. Software
Experiment Steps
To calculate the two parts of the G solar we first poisoned our base to take angle theta = 90 with the sun as cos (90) = 0 so G solar = G diffuse
We then calculate data using lab View program which we will explain later that collect data and calculate mean value
Second with the base at angle 30 with earth we calculate sun angle at this time and we get the angle between sun and the aluminum plate to be 18 degree
๐๐๐ = ๐๐๐ข๐ก
๐ผ๐บ๐ ๐๐๐๐ + ๐๐๐๐ ๐๐ฆ4 + ๐๐๐๐ ๐ข๐๐
4 = 2๐๐๐๐ ๐ข๐๐4 + 2โ(๐๐ ๐ข๐๐ โ ๐๐ ๐ข๐๐)
Results
๐บ๐ ๐๐๐๐ = 2๐๐๐๐ ๐ข๐๐
4 + 2โ ๐๐ ๐ข๐๐ โ ๐๐ ๐ข๐๐ โ 2๐๐(๐๐ ๐๐ฆ4 + ๐๐ ๐ข๐๐
4
๐ผ
๐บ๐ ๐๐๐๐ = 1.944 โ 10โ8 ๐๐ ๐ข๐๐4 โ ๐๐ ๐๐ฆ
4 โ ๐๐ ๐ข๐๐4 + 94.66(๐๐ ๐ข๐๐ โ ๐๐ ๐ข๐๐
๐๐ ๐๐ฆ = 0.86 ๐๐๐๐
๐ฎ๐ซ๐๐๐๐๐๐ = ๐๐๐. ๐๐ ๐พ/๐๐
๐ฎ๐ซ๐๐๐๐๐ = ๐๐๐. ๐๐๐พ/๐๐
Future Work
Knowing the G solar direct and diffuse for specific material, we could replace the plate on the base with any unknown material we want to know its emissivity and calculate it using same equations.
Make the LabVIEW program fully automated in gathering
information about the weather and the surrounding environment with very few inputs
References
I. Yunus A. Gengel, and Robert Turner, " Fundamentals of Engineering Thermodynamics ",
McGraw Hill,2014 , 8th Edition
II. Yunus A. Cengel, โHeat and Mass Transfer, A Practical Approach,โ 3rd Edition, McGraw Hill,
2006.
III. Sultan A (2004) Absorption/regeneration non-conventional system for water extraction from
atmospheric air. Renew Energy 29:1515โ1535
IV. Berdahl P, Fromberg R (1982) The thermal radiance of clear skies. Sol Energy 29:299โ314
V. Khedari J, Waewsak J, Thepa S, Hirunlabh J (2000) Field investigation of night radiation cooling
under tropical climate. Renew Energy 20:183โ193
VI. Cooper PI, Christie EA, Dunkle RV (1981) A method of measuring sky temperature. Sol Energy
26:153โ159 Heat Mass Transfer (2011) 47:1171โ1180 1179 123
VII. Enz JW, Klink JC, Baker DG (1975) Solar radiation effects on pyrgeometer performance. J Appl
Meteor 19:1297