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

[EnergyPlus_Support] Re: How to define ventilation rate to get proper HVAC system energy consumption

Dr. Li:

The thing I am not quite clear about is that we have different ways to tell E+ that we want to have a certain amount of ventilation into the zone.  We can use ZoneInfiltration or ZoneVentilation:DesignFlowRate or Sizing:Zone.  

If our purpose is to find the actual HVAC energy consumption, which one of these three should we use?

My understanding is as follows:

(1)if we use ZoneInfiltration, the load brought in by outside air should be the same.  But we lose the energy consumption by the fan because all ventilation is caused by infitration.  No fan is needed.

(2)we do not have to have Sizing:Zone/System/Plant if our goal is to get actual energy consumption of the HVAC system.  All we need to do is to use branchers/objects/nodes/...to correctly model the HVAC system.

Am I right?  Thanks!


--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, YuanLu Li <yli006@...> wrote:
>
> 
> Hi, Xing
>  ZoneInfiltration:DesignFlowRate  would add some air into the zone with a fan.  The fan power is listed in the report as virtual fan.
> ZoneVentilation:DesignFlowRate does not use fan.  The air flows through cracks.
> Sizing:Zone is required to provide design information to the program to size the zone equipment.. You will need system and plant sizing as well.  If you use template as input, these will be provided by the template expansion program. Total HVAC energy consumption would be the sum of all the components, fans, pumps, compressors.  GSHE has a circulating pump.  Tower has both pump and fan.  Chiller is the heat pump which has compressor and pump.  The zone equipment has  a fan per zone or a common fan in the AHU. When the heat pump cannot provide the heating, additional heating power is added.
> 
>  Dr. Li   
>  To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> From: xing.shi.2006@...
> Date: Mon, 15 Aug 2011 11:40:37 +0000
> Subject: [EnergyPlus_Support] How to define ventilation rate to get proper HVAC system energy consumption
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
>  
> 
> 
> 
>   
> 
> 
>     
>       
>       
>       In the following 3 objects, which one should we use to model HVAC system energy consumption:
> 
> 
> 
> ZoneInfiltration:DesignFlowRate
> 
> ZoneVentilation:DesignFlowRate
> 
> Sizing:Zone
> 
> 
> 
> Our HVAC system is chiller plus cooling tower.  Air system is constant volume fan.  Heating provided by ground source heat pump.
> 
> 
> 
> Thanks!
>




------------------------------------

Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

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 currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
Yahoo! Groups Links

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

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/join
    (Yahoo! ID required)

<*> To change settings via email:
    EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx

<*> 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/