Re: [EnergyPlus_Support] simulation time step

[Adriana Angelotti <Adriana.Angelotti@xxxxxxxxx>]

Differences are small if you compare results for time steps shorter than 1h 
(10m, 15m and 30m).
But using 1h as the time step can produce differences of 0.5-1°C in the 
free floating temperature of a room.

I know that weather data is interpolated for time steps shorter than 1h and 
I guess the difference I see
in the results is due to the interpolation.
So if I use a short time step I can follow better the dynamic of the 
building, but I introduce some errors
because of the interpolation of weather data.
On the other side if I use 1h I'm sure I'm not introducing interpolation errors
but maybe I miss something in the dynamic.
So I wonder what is the best choice.
Thank you

Adriana A.

At 14.06 04/02/03 -0600, you wrote:
>What kind of differences are you seeing?  They should be small, and
>hourly results should be very similar.  The hourly weather data is
>interpolated for shorter time steps.
>
>On 3 Feb 2003, at 14:50, Adriana Angelotti wrote:
>
> > Hello everybody,
> >
> > I'm trying to reproduce some experimental data on a free floating
> > building with an Energy Plus simulation. I see that using different
> > time steps (10m, 15m, 30m and 1h) produces different results.
> >
> > So I wonder if there is some general consideration that can be used in
> > the choice of the proper time step, besides the one I found on EP
> > manual (15 minutes for a simulation without HVAC and 10m for a
> > simulation with HVAC).
> >
> > Besides this, I wonder what is the meaning of a simulation with a time
> > step shorter than 1h, if the weather data time step is 1h.
> >
> >
> > I would appreciate your help.
> > Thank you
> >
> > Adriana Angelotti
> >
> >
> >
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