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[EnergyPlus_Support] Re: Modeling VRV system
I heard from somebody in DAIKIN that they are testing VRV modeling section for energy plus.
--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "bajic.vladimir@xxxxxxxxx" <bajic.vladimir@...> wrote:
>
>
>
> Sent from my Verizon Wireless Phone
>
> ----- Reply message -----
> From: "James V Dirkes II, PE" <jim@...>
> Date: Thu, Feb 10, 2011 9:21 am
> Subject: [EnergyPlus_Support] Re: Modeling VRV system
> To: <EnergyPlus_Support@xxxxxxxxxxxxxxx>
>
> The approach I described is for a LEED project, but has not been submitted
> yet.
>
>
>
> The Building Performance Team
> James V. Dirkes II, P.E., LEED AP
> 1631 Acacia Drive NW
> Grand Rapids, MI 49504
> 616 450 8653
>
>
>
> From: EnergyPlus_Support@xxxxxxxxxxxxxxx
> [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of fm1n0
> Sent: Thursday, February 10, 2011 9:05 AM
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> Subject: [EnergyPlus_Support] Re: Modeling VRV system
>
>
>
>
>
> I really appreciate your help, James. Thank you.
> Have you ever submitted this type of VRF-approximate model for LEED
> certification?
> Has anybody out there submitted any other these "almost-VRF" for LEED?
>
> I would though, if you don't mind and have some free time for it, if you
> could further describe your method.
>
> Thank you again.
> Have a great day!
>
> Francisco
>
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com> , "James V Dirkes II, PE"
> <jim@> wrote:
> >
> > Dear Francisco,
> >
> >
> >
> > I do not think that you can properly simulate VRF with individual zone DX
> > systems.
> >
> >
> >
> > A VRF system essentially responds to the total system load. If, for
> > example, 5 zones are in heating mode, and 6 are in cooling mode, you might
> > have a cooling load that is a small percentage of the total capacity. This
> > can be true even if the 6 cooling mode zones are operating at 100% of
> their
> > capacity. In this situation, the true part load of the system may be only
> > 9% (as an example).
> >
> >
> >
> > I hope that is clear (I don't have time now for more details)!
> >
> >
> >
> > For that reason, I think a better approach is:
> >
> > · WSHP in each zone with COP = 1000 (yes, one thousand so that there
> > is essentially no compressor heat added at the zone level)
> >
> > · WSHPs served by a chiller (COP= 1000) and boiler (efficiency =
> > 1.0)
> >
> > · Create a custom meter for the chiller and boiler energy
> >
> > · Via post-processing (e.g., Excel spreadsheet), calculate the net
> > heating / cooling load and apply a part load factor appropriate for the
> VRF
> > manufacturer
> >
> > · Calculate a new total for electric usage based on the new
> > calculated VRF electricity use.
> >
> >
> >
> > The Building Performance Team
> > James V. Dirkes II, P.E., LEED AP
> > 1631 Acacia Drive NW
> > Grand Rapids, MI 49504
> > 616 450 8653
> >
> >
> >
> > From: EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com>
> > [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com> ] On Behalf Of fm1n0
> > Sent: Thursday, February 10, 2011 7:28 AM
> > To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com>
> > Subject: [EnergyPlus_Support] Re: Modelling VRV system
> >
> >
> >
> >
> >
> > Hi.
> > I'm attempting the approximate-VRF method mentioned below.
> > COIL:COOL/HEAT:DX:MULTISPEED
> > 1. Should the rated conditions be the same for all speeds?
> > 2. Curves: are they defined by E+ or user-defined?
> >
> > InputOutput p.1477
> > "rating point (the air entering the cooling coil at 26.7°C drybulb/19.4°C
> > wetbulb and air entering the outdoor condenser coil at 35°C drybulb/23.9°C
> > wetbulb)"
> > InputOutput p.1514
> > "the multispeed coil object is described by specifying the performance at
> > different operating speeds at rated conditions"
> >
> > thanks
> >
> > Francisco
> >
> > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com>
> > <mailto:EnergyPlus_Support%40yahoogroups.com> , "alberto" <ahneto@>
> > wrote:
> > >
> > > Dear Mark,
> > >
> > > The four step variation I mentioned is related to the menu
> > COIL:COOLING:DX:MULTISPEED where we can set 04 different speeds where the
> > model of such coil can be simulated. For each speed, you can provide all
> the
> > parameters that can represent the coil but it is different from a VRF
> > because the system works in a continuous variation of these parameters but
> I
> > think it is the closest model EnergyPlus have at the moment.
> > >
> > > Alberto
> > >
> > > ----- Original Message -----
> > > From: Zoeteman, Mark R.
> > > To: ahneto@
> > > Cc: EnergyPlus_Support@xxxxxxxxxxxxxxx
> <mailto:EnergyPlus_Support%40yahoogroups.com>
> > <mailto:EnergyPlus_Support%40yahoogroups.com>
> > > Sent: Monday, May 24, 2010 11:40 AM
> > > Subject: [EnergyPlus_Support] Modelling VRV system
> > >
> > >
> > >
> > >
> > >
> > > Alberto,
> > >
> > > Is following page 14 from "Tips and Tricks for Using EnergyPlus" what
> you
> > are referring to model VRV system? I don't see reference to a four stepped
> > variation you referred to in your response to Felipe Agustin.
> > >
> > > Mark Zoeteman, FTC&H
> > >
> >
>
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