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Re: [EnergyPlus_Support] Precooling chilled water return
This should work in E+. You would need to use constant flow chillers and
the chillers should not be auto-sized (or at least the smaller one). The
only problem I see is that you can not have a significant difference in
the capacities of the series chillers. The reason is that both chillers
will operate at the same evaporator volumetric flow rate (and the
performance curves should account for off-design flow rates). There is
an upper (and lower) limit to the water velocities through a chiller's
heat exchanger. Above the upper limit, erosion of heat exchanger will be
excessive (and so will the pressure drop). Below the lower limit there
is a chance of freezing the heat exchanger or reducing oil transport
through the refrigeration system. Of course this will not hurt the
simulation, but you want to be as close to reality as possible. And if
you actually built a chiller with an over-sized heat exchanger, you
would not have this problem. Check with manufacturers for appropriate
ranges of water flow rates through the evaporators for your type of
chiller. The same holds true for the condenser heat exchangers, but you
could pipe the condensers in parallel.
zhaicq98 wrote:
>
> I have a big and a small water cooled vapor compression chiller in the
> system. They are configured in series, but the chilled water flowrate
> of the
> big chiller is much greater than the small one. The small chiller is
> used to
> pre-cool a portion of the chilled water return to the big chiller.
>
> I wonder if EnergyPlus is able to handle this system. Thanks for your
> help.
>
> -Chaoqin
>
>
--
Richard A. Raustad
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