AW: view factors

["Dr. Karl-Christian Rauch" <Rauch-Muenster@xxxxxxxxxxx>]

Back to the roots, ad fontes,

please have a look to VDI Warmeatlas, Kapitel Kb1 to Kb10 and
to the Chapter FIJ* as well as Chapter FIJ1* in 
 NBSLD, the Computer Program for Heating and Cooling Loads in
Buildings, U.S. Department of Commerce (NBS)
Author: Tamami Kusuda, July 1976

auszuleihen bei: Uni-Bibliothek Hannover, Technische Informationsbibliothek
                         RA 968(69)

Kind regards
Dr.Karl-Christian Rauch
SAP ABAP/4 Application-Developer

-----Ursprungliche Nachricht-----
Von:	Joachim Klinner [SMTP:joachim.klinner@gmx.de]
Gesendet am:	Donnerstag, 31. Mai 2001 14:30
An:	trnsys@relay.doit.wisc.edu
Betreff:	view factors

Hi everyone,

I've got a question regarding 'view factors' used in TYPE19-DETAILED
ZONE (trnsys 14.2). In 'geometry mode 2' view factors from surface i to
surface i+1,..., N are to be entered. What is the mathematical
description of this view factor? Is it the same as following?:

F_ij= Integral_above_A_i   Integral_above_A_j cos(alpha_i)*
cos(alpha_j)*1/r? *dA_i*dA_j

i, j = surface number
A_i, A_j =Area of surface i, j
F_ij = view factor from surface i to surface j
N =  number of surfaces comprising zone
r =  distance between dA_i and dA_j
alpha_i = angle between surface normal of dA_i and vector r
alpha_j=  angle between surface normal of dA_j and vector r

Can anybody help?

Thanks and regards,

******************************************************
Joachim Klinner, Engineer <joachimk@mail.fo.fh-koeln.de>
ILB at  University of Applied  Sciences Cologne
adr.:   Institut fur Licht- und Bautechnik an der FH-Koln
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