[esp-r] shading by a semi-transparent obstruction ....... ?

[Pueltz, Gunter]

A question to the ESP shading specialists:

I have to model a very special type of external shading:
The complete building shows an "external envelope",
which consists of parallel metal tubes (see attached figures:
section and view of this "envelope").
This external grid of horizontal tubes shows a shading coefficient
of appr. 45% (55% is free open area). Now my question:

How to model a semi-transparent (appr. 55% transmission) shading ?
Does ESP-r calculate the transmission of the incident solar radiation
through a transparent external obstruction (e.g. a glazing with 
transmission of 55%) in a correct way ? 

If transparent obstruction does not work: Any other idea ?
I do NOT want to model hundreds of single tubes ........ !!!!

Regards,
Gunter 

--
Gunter Pültz

Müller-BBM GmbH
Robert-Koch-Straße 11
82152 Planegg
Telefon +49 (0)89 85602 - 336
Telefax +49 (0)89 85602 - 111
http://www.MuellerBBM.de 

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