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<DIV><FONT size=3>
<DIV><FONT size=3>Mike Andelman wrote:</FONT></DIV>
<DIV><FONT size=3>The frustrating thing for any DOE2 user who's been using the
program since it was CalERDA is that some real progress has developed over the
last few years with 2.1E, 2.2, and PowerDOE. Now it appears that the
progress will be put on hold as we patiently wait several years for EnergyPlus.
</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=3>my reply:</FONT></DIV>
<DIV>The work on DOE-2 has not slowed down; we are continuing at an equal or
higher pace than the last 10 years. We are (like others), however,
putting<FONT size=3> a lot of time and $ into the user interface's to make the
programs easier to use and more reliable. For DOE-2, we just finished
adding a number of features (which will be in versions posted within the next
couple months) including photovoltaic systems (PV modules/arrays, inverters,
plus effects of array mounting including shading of building surfaces),
latent/sensible energy recovery ventilators (ERV's), spaces which include ice
rinks (model includes ice/room radiative exchange and under floor losses/heating
system.) We are continuing work in a number of other areas to improve HVAC
models for both design and energy calculations and will continue to post these
versions as they become available.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=3>Doug Maddox wrote:</FONT></DIV>
<DIV>"Also, is DOE2.2 more friendly to function writing than DOE2.1E? What
about<BR>DOE2.3?<FONT size=3>"<BR></FONT><FONT size=3></FONT></DIV>
<DIV><FONT size=3>my reply: The function feature is not yet in a posted 2.2
version; it will be available in the next posted update. It works like
before, but now all HVAC equipment will have "access points." The later
version you refer to (2.3?) is under development and has no designation
(name/number) or release date yet so should not be confused with products we
have posted for general use. All versions we post for general use are ready for
such use; all software, however, has bugs ... they just have not yet all been
discovered - we fix ours are quickly as possible when discovered (or at least
give you a work-around.)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=3>Our "next generation" program includes a component based
HVAC model in which pressure and temperature, and resultant flow, are
explicitly modeled; this allows the detail modeling, for example, of components
on a refrigerant loop (like refrigeration systems - or chillers), as well
as secondary coolants (glycol, brine) or water loops. For example, you can
describe the refrigeration "plant" as an interconnection of evaporator(s),
suction lines, compressor(s), high side lines and condenser(s) with controls and
also select a refrigerant; all these components can be fetched from a large
library of such components and assembled into a very complex system. The piping
models, for example, allow the definition of a complete real pipe network and
the calculation includes details such as the change in fluid properties, film
coefficients, and pipe losses as the working fluid flows through the
system. The coil models, for example, include DX coils that track frost
accumulation and model alternative defrost mechanisms and controls. The
overall calculation technique includes iteration with a range of algorithms to
assure very rapid convergence to a "correct" solution.</FONT></DIV>
<DIV><FONT size=3></FONT> </DIV>
<DIV><FONT size=3>Again this is NOT a product; it is a product research project
in the early stages of beta. At this time only a subset of HVAC equipment is
available in this new program; our focus at this time is refrigeration and HVAC
systems for facilities like supermarkets and refrigerated warehouses. A working
beta version is available; it is not intended for general distribution. We
expect it to take at least a year before the full range of HVAC equipment is
implemented and longer to complete beta testing. Those interested in
trying it out are welcome to ask for details. Like our other "engines", if
a general release product results from this project it will be
freeware.</DIV></FONT>
<DIV></FONT><FONT size=3>---<BR>Jeff Hirsch<BR>James J. Hirsch &
Associates<BR>Building Performance Analysis Software & Consulting<BR>12185
Presilla Road<BR>Camarillo, CA 93012-9243 USA<BR>phone: (805)
553-9000<BR>fax: (805) 532-2401<BR>email: <A
href="mailto:Jeff.Hirsch@DOE2.com">Jeff.Hirsch@DOE2.com</A><BR>web: <A
href="http://DOE2.com">http://DOE2.com</A></FONT></DIV></DIV><PRE>
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