[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[EnergyPlus_Support] Re: About the WindAC



Stewart,

I understand that air distribution systems are not common in Hong Kong
and many other parts of the world.

However, you can still model your system using an air
loop as shown in the FurnaceWithDXSystem.idf example file. You can
simply tell the system not to bring in any outdoor ventilation air
through that system (if appropriate). And unless you use EnergyPlus'
detailed Air Distribution System model (ADS Simulation, ADS node, ADS
element data, etc.), the air loop is "perfect" and no heat
gains/losses nor air leakage to/from the air loop is modeled.

Alternately, you should be able to use Air Conditioner:Window:Cycling
along with Baseboard Heater:Electric:Convective. Look at the
WindACAuto.idf example file, and replace the BASEBOARD
HEATER:Water:Convective radiative/conventive unit with Baseboard
Heater:Electric:Convective in the ZONE EQUIPMENT LIST. Obviously no
hydronic loop is required for the Baseboard Heater:Electric:Convective
object, so you won't need to use the hot water plant loop and its
associated objects shown in the example file.

Don



--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "beyangj" <beyangj@h...>
wrote:
> Dear Don,
> Thank you very much for your reply. I have looked at the example 
> file FurnaceWithDXSystem.idf. It can be used for residential 
> heating/cooling,but it involves an air distribution system. The air 
> distribution system is not common in Hong Kong, how can I model 
> residential cooling/heating with electric heating coil without an 
> air distribution system?
> 
> Best,
> 
> Stewart  
> 
> 
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "donbshireyiii" 
> <shirey@f...> wrote:
> > Stewart:
> > 
> > As you have found, the window air conditioner object can only 
> provide
> > cooling, not heating.  If you look at the WindACAuto.idf example 
> file,
> > you see that baseboard heating is used along with the window air
> > conditioner in this particular example file.
> > 
> > A packaged terminal heat pump object will be added in a future 
> version
> > (Fall 2005 or Spring 2006) which will allow both cooling and 
> heating.
> > 
> > In the meantime, I suggest that you look at the example file
> > FurnaceWithDXSystem.idf.  You can use a FURNACE:BLOWTHRU:HEATCOOL
> > object in a air loop to model cooling with the
> > COIL:DX:CoolingBypassFactorEmpirical and you can specify
> > COIL:ELECTRIC:HEATING for heating.
> > 
> > Don
> > 
> > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "beyangj"
<beyangj@h...>
> > wrote:
> > > Dear,
> > > I'm doing a simulation for a residential building. The window 
> air 
> > > conditioner model in EnergyPlus is "cooling only",  but there 
> need 
> > > heating in the winter in my model, so I chose the 
> > > COIL:ELECTRIC:HEATING for heating, and the 
> > > COIL:DX:CoolingBypassFactorEmpirical is followed by the 
> > > COIL:ELECTRIC:HEATING.
> > > When I set the items as follow,
> > > 
> > > NODE LIST,
> > >     GAB1Inlets,              !- Node List Name
> > >     GAB1 Heating Coil Outlet Node; !- Node_ID_1
> > > 
> > > NODE LIST,
> > >     GAB1Exhausts,            !- Node List Name
> > >     GAB1WindACAirInletNode;  !- Node_ID_1
> > > 
> > > COIL:Electric:Heating,
> > >     GAB1 Heating Coil,       !- Coil Name
> > >     HEAT-SCHED-B1,           !- Available Schedule
> > >     1,                       !- Efficiency of the Coil
> > >     autosize,                !- Nominal Capacity of the Coil {W}
> > >     GAB1WindACAirOutletNode, !- Coil_Air_Inlet_Node
> > >     GAB1 Heating Coil Outlet Node;  !- Coil_Air_Outlet_Node
> > > 
> > > COIL:DX:CoolingBypassFactorEmpirical,
> > >     GAB1WindACDXCoil,        !- Coil Name
> > >     System Available Schedule-B1,  !- Availability Schedule
> > >     autosize,                !- Rated Total Cooling Capacity
> > (gross) 
> > > {W}
> > >     autosize,                !- Rated SHR
> > >     3.0,                     !- Rated COP
> > >     autosize,                !- Rated Air Volume Flow Rate
{m3/s}
> > >     GAB1WindACFanOutletNode, !- Coil Air Inlet Node
> > >     GAB1WindACAirOutletNode, !- Coil Air Outlet Node
> > >     WindACCoolCapFT,         !- Total Cooling Capacity Modifier
> > Curve 
> > > (function of temperature)
> > >     WindACCoolCapFFF,        !- Total Cooling Capacity Modifier
> > Curve 
> > > (function of flow fraction)
> > >     WindACEIRFT,             !- Energy Input Ratio Modifier 
> Curve 
> > > (function of temperature)
> > >     WindACEIRFFF,            !- Energy Input Ratio Modifier 
> Curve 
> > > (function of flow fraction)
> > >     WindACPLFFPLR,           !- Part Load Fraction Correlation 
> > > (function of part load ratio)
> > >     CycFanCycComp;           !- Supply Air Fan Operation Mode
> > > 
> > > AIR CONDITIONER:WINDOW:CYCLING,
> > >     GAB1WindAC,              !- name of window AC unit
> > >     System Available Schedule-B1,  !- availability schedule
> > >     autosize,                !- maximum air flow rate {m3/s}
> > >     autosize,                !- maximum outside air flow rate 
> {m3/s}
> > >     GAB1WindACAirInletNode,  !- air inlet node
> > >     GAB1WindACAirOutletNode, !- air outlet node
> > >     GAB1WindACOAInNode,      !- outside air node
> > >     GAB1WindACExhNode,       !- air relief node
> > >     GAB1WindACOAMixer,       !- outside air mixer name
> > >     GAB1WindACFan,           !- fan name
> > >     GAB1WindACDXCoil,        !- DX cooling coil name
> > >     CycFanCycComp,           !- operation mode
> > >     blow through,            !- fan placement
> > >     0.001,                   !- Cooling Convergence Tolerance
> > >     COIL:DX:CoolingBypassFactorEmpirical;  !- Cooling coil type
> > > 
> > > there were such error messages as follow in the ERR file after 
> > > running the IDF file,
> > >  
> > >    ** Severe  ** Error in Node="GAB1 HEATING COIL OUTLET NODE", 
> > > ZoneInlet node did not find an outlet node.
> > >    **   ~~~   ** Reference Object=CONTROLLED ZONE EQUIP 
> > > CONFIGURATION, Name=GAB1
> > >    ************* No node connection errors were found.
> > >    ** Warning ** The following lines are "Orphan Objects".  
> These 
> > > objects are in the idf
> > >    **   ~~~   **  file but are never obtained by the simulation 
> and 
> > > therefore are NOT used.
> > >    **   ~~~   **  See InputOutputReference document for more
> > details.
> > >    ************* Object=COIL:ELECTRIC:HEATING=GAB1 HEATING COIL
> > >  
> > > I just found the item definitions in Air 
> Conditioner:Window:Cycling 
> > > are that the air inlet node should be one of the zone exhaust 
> nodes 
> > > for the zone which the window air conditioner is cooling, and
the
> > air 
> > > outlet node should be one of the inlet air nodes for the zone 
> which 
> > > is being cooled. I wondered whether I can add the 
> > > COIL:ELECTRIC:HEATING to the window air conditioner system. If 
> so, 
> > > how can I connect them?  Thanks in advance!
> > > 
> > > Best,
> > > 
> > > Stewart




The primary EnergyPlus web site is found at:
http://www.energyplus.gov

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are not allowed -- please post any files to the appropriate folder in the Files area of the Support Web Site.
 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/

<*> To unsubscribe from this group, send an email to:
    EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/