Mr Fateh

Could you provide more data about your solar radiation measurements?

Direct solar radiation is measured by heliometer directly or by measuring total radiation by pyranometet?

If you used pyranometer , what is the tilt angle of it?

Also, how you measure diffuse radiation and at any tilt angle?

Best Regards

Amirreza,

I would begin with the following book if I were you:

M. Iqbal, "An Introduction to Solar Radiation", Academic Press 1983.

The book is a classic. Most probably you will get your answer there.

-Sanjay

Dear Amirreza,

You can also try my lecture notes on solar radiations, particularly the one attached would be much helpful.

If you are working in an urban area (buildings &trees etc. nearby), try going through the paper as well.

Good luck!

http://www.naveedurrehman.com/post/Solar_Radiations_Chap_3_from_Fundamentals_of_Solar_Energy_Engineering-158.htm

Article A novel method for determining sky view factor for isotropic...

Dear Amirreza

Calculate the theoretically receivable solar irradiation on a horizontal and subsequently, on a vertical plate in your case study. Then you can find a ratio for that: X=IT,v / IT,h. 

Then you can find IT,v=X*IT,h.

Note that you need to find an average monthly value for each hour of the day for X, as incidence angle varies during the day and also over the seasons, for making better approximations. 

Good Luck 

thank you very much for your attentions

Dear Sanjoy Roy,

how we can get this book freely?

Thank you

Hi Mohamed,

I am not sure how to answer that question !! :-) :-)

Perhaps you can get it procured through your library ??

All I can say is (and I am sure there are many who would support me on this !) that the book by Iqbal is an excellent reference on the conventional concepts of solar irradiation.

For relatively recent developments, we may require other references.

-Sanjay

AoA Mohamed,

There are few more books you learn from:

1. Solar Engineering of Thermal Processes

by John A. Duffie, William A. Beckman

2. Solar Energy Engineering

by S Kalogirou

3. Solar Radiation and Daylight Models

by Tariq Muneer

- NR

hi friends, I read the book but I

I read the book but I couldn't find  the angle of sun and normal for the vertical plan on  north,east and west ?