[esp-r] Re: question about the Ish module

[Geissler Achim]

Dear Gian Luca, Jon, others

I agree that it would be very good to extend the properties of exterior obstructions with reflectance. We suggested this some years ago in context with the increasing use of quite reflective "Louvre" types of shading elements (brushed steel or aluminum, light grey or white carbon wings and similar) on commercial high rise buildings.

Also, reflective obstructions would surely enhance the accuracy of calculated gains (and daylighting performance) for northerly elevations facing reflective opposite buildings.

Recently, obstructions were extended for transparency. Therefore, the next logical step would be to add reflectivity. To my knowledge, none of the comparable simulation programs takes this into account, either. 

Best
Achim



-----Ursprüngliche Nachricht-----
Von: esp-r-bounces at lists.strath.ac.uk [mailto:esp-r-bounces at lists.strath.ac.uk] Im Auftrag von Gian Luca Brunetti
Gesendet: Dienstag, 2. August 2011 04:02
An: esp-r at lists.strath.ac.uk; jon at esru.strath.ac.uk
Cc: gianluca.brunetti at polimi.it
Betreff: [esp-r] Re: question about the Ish module

I think that the main limitations of the program would be the following:
- it would underestimate the increase of insolations values in the case that even the gain of the most insolated surface turns out to be increased by the reflections due to obstructions, since that value is kept fixed to scale all the others
- nothing would be done to take into account the irradiation increase due to the reflections caused by the obstructions due to the sky diffuse component
- the computations would just regard interior surfaces and not exterior ones