[esp-r] Re: temperatures, g-value and changing heat transfer coefficients

[Jon Hand (clcv10)]

A novice user had a series of questions....

> It's a simple room with given settings. I
> would like to change the thermal heat transfer coefficients of the
> constructions.

There is a facility in the project manager that gives several options
for fixing the convective heat transfer coefficient at the inside
and outside face of surfaces.  In the project manger look in
  browse/edit/simulate -> zone composition ->  convection coefficients

> The window should have a g-value of 75%.

A g-value is reported in Esp-r it is not an input variable.  Use WIS  
(window
information systems) or the LBL Window 5.1/5.2 applications to derive  
the
optical properties of your specific glazing and then you will have to  
go into
the optical database and input the data.  You might find that there  
is an
existing optical property set that is close to what you need. Look in
   database management ->  optical properties

Optical properties are referenced by constructions so you will also
need to look in the constructions database to see if there is a glazing
construction that is close to what you need, otherwise you will have
to create a new construction and associate it with your optical  
properties
set.

> And my third
> question: How can i give the room start up temperatures for the  
> air- and
> the surfaces.
>
This is usually done by including a pre-simulation time in the  
simulation
so that temperatures have evolved sufficiently prior to the simulation
commencing.  If the specification says that all zones need to be 20C
at midnight at the start of the assessment then you might choose to  
define
a zone control that controls to that temperature.  Generally we do not
support the idea of fixing surface temperatures - they are the result of
all the other energy and air flows within the model.

-ESRU