Re: Simulating a GrassRoof

["Anil Misra" <anil_misra@xxxxxxxxxxxxxxxx>]

Dear Dr Rauch,

I thank you very much for both the mails. I have been able to get rid of the
forrtl: error(63)
but I do not fully understand how. I discovered that inputs for one of the
zones of the building (to be simulated) was not complete. As soon as I
completed that zone, the error was gone.

I am presently working on a project with Dr A Kumar (Dr Ashvini Kumar) who
was the coauthor of the paper you have mentioned, and I have worked earlier
with Prof. M S Sodha.

The grass roof generates two thermal  effects:

1. It absorbs heat from the roof, and eventually from the indoor air. I
tried to simulate this effect using roof with a negative gain and this trick
seems to be working. I still need to verify that the results are reasonable.

2. The grass roof lowers the ambient temperature by a couple of degrees
hence changing the solair temperature. It is the effective solair
temperature that I need to simulate, and I am still looking for a simple
solution to this. Any ideas?

I thank you once again for very useful suggestions.

With kind regards,

Anil Misra


----- Original Message -----
From: Dr.Karl-Christian Rauch <Rauch-Muenster@t-online.de>
To: <trnsys@relay.doit.wisc.edu>
Sent: Friday, March 29, 2002 17:34
Subject: Re: Simulating a GrassRoof


> Dear Anil,
> I remember an article in APPLIED ENERGY, Solar Energy Research
> Volume 7 Nos. 1-3 November 1980, pp229-242
> Applied Science Publishers Ltd., England, 1980
>
> Heating and Cooling Buildings by Flow of Water over the Roof
> Authors: M.S.Sodha, A.Srivastava, A.Kumar, and G.N.Tiwari
> Centre of Energy Studies, Indian Institute of Technology,
> Hauz Khas, New Delhi, 110029, India
>
> This paper presents an analysis for the reduction of the heat flux
> that occurs by constant flow of water in a network of pipes buried
> in a roof.. An air gap is introduced into the roof to achieve maximum
> thermal load levelling (summer like winter).
>
> Not quite yet what you are searching for; but indeed I think, this
> is an interesting paper for your job.
>
> Kind regards
> Dr.Karl-Christian Rauch
>
> ----- Original Message -----
> From: "Anil Misra" <anil_misra@mantraonline.com>
> To: <trnsys@relay.doit.wisc.edu>
> Sent: Friday, March 08, 2002 4:53 PM
> Subject: Simulating a GrassRoof
>
>
> > Dear TRNSYS users,
> >
> > I would like to receive suggestions on the modeling of a grass roof,
which
> > is a cost effective passive cooling technique in our climate.
> >
> > This concept of GrassRoof is being promoted by architects and designers
in
> > new buildings. I have to evaluate the contributons of a GrassRoof to the
> > reduction in cooling loads.
> >
> > The construction of a typical GrassRoof is given in the attached MS Word
> > File.
> >
> > Thanks
> >
> > Anil Misra
> > Tata Energy Research Institute
> > India Habitat Centre
> > Lodhi Road
> > New Delhi 110003
> > India
> >
> >
> >
> >
>