Re: [EnergyPlus_Support] Re: rated air volume flow rate of CoolingBypassFactorEmpirical

["Michael J. Witte" <mjwitte@xxxxxxxx>]

On 17 Sep 2002, at 4:38, rmp4aup6 wrote:

> Hi, everyone:
> Especially for Mike Witte, thank you very much!!
> 
> B-1.
> I have checked the maximum air flow rate in the Window AC object is
> the same as the Rated air volume flow rate in the DX coil object. but
> the error message still showed after simulation.

You must compare the ratio of air flow to cooling capacity and make 
sure that it is within the limits specified in the I/O reference.  If 
you are still receiving the error message, then your airflow rate is 
either too high or too low for the specified cooling capacity.


> 
> Further, I tried to change the setting cooling temperature from 26C to
> 24C in DAYSCHEDULE object, then the simulation ran successfully. Do
> you have any ideas about that??
> 
> but even the simulation ran susscessfully for the case of 24C setting,
> the mean air temperautre in that zone is not fixed as the setting
> cooling tempertuare(24C).

As long as you are receiving the above error message, your simulation 
results are probably not valid.

> 
> 
> by the way, Is there any simple example talking about the central
> cooling system in a zone or for one building?? 
> 

The files in the Examples folders.  

Mike


> 
> 
> --- In EnergyPlus_Support@y..., "Michael J. Witte" <mjwitte@g...>
> wrote: > A.  If you have windows, solar gains will heat the space to
> be warmer > than the outside air.  Also, internal gains such as people
> and > equipment will heat the space.  So it is quite possible for an >
> unconditioned space with no ventilation to get this warm.  For >
> example, think of a closed up car sitting in the hot sun. > > B-1. 
> The restriction on airflow is "Rated Air Volume Flow of >
> CoolingBypassFactorEmpirical should be between 0.00004699-0.00006041 >
> m3/s PER WATT OF RATED TOTAL COOLING CAPACITY."  The error message is
> > indicating that your airflow rate is not consistent with the rated >
> capacity of the DX coil.  Note that you must make sure that flow >
> rates and capacities are consistent in the Window AC object and the >
> DX coil object.  They are not automatically matched. > > B-2.  You
> should see the setpoint properly maintained once you get > rid of the
> air flow errors. > > Mike Witte > > > > On 13 Sep 2002, at 12:11,
> rmp4aup6 wrote: > > > hello, sorry to bother you everyday!! > > > > I
> am running a simulation for a room with 24m*11m*4m > > > > what
> strange is that > > A. for the case without air conditioners > > the
> outdoor dry bulb is 35C at noon, but the mean air temperature in > >
> that at noon is about 54C, is it normal?? > > > > B. for the case with
> 5 window air conditioners > > Although the simulaiton completed
> successfully , it shows some warning > > messages that I don't know
> how to solve. As below: > > > > ** Warning **
> COIL:DX:CoolingBypassFactorEmpirical "ZN001WINDACDXCOIL" > > - Air
> volume flow rate per watt of rated total cooling capacity is out > >
> of range on MM/DD HH:MM.mm= 7/31 07:35.00 > > > > ** Warning **
> COIL:DX:CoolingBypassFactorEmpirical > > "ZN001WINDACDXCOIL5" - Air
> volume flow rate per watt of rated total > > cooling capacity is out
> of range error continues...100 > > > > ** Warning ** AIR
> CONDITIONER:WINDOW:CYCLING -- Exceeded max > > iterations while
> adjusting compressor runtime to meet the zone load > > within the
> cooling convergence tolerance. **   ~~~   ** For > >
> WindowAC=ZN001WINDAC, Iterations=15 > > > > B-1 > > the reference said
> that the Rated Air Volume Flow of > > CoolingBypassFactorEmpirical
> should be between 0.00004699-0.00006041 > > m3/s, but I set it as 0.6,
> the same as the Example WindAC.idf. > > something wrong?? > > > > B-2
> > > I set the cooling setpoints to be 24C, but I found that the mean
> air > > temperature is not steady. most of the time is below 23C > > >
> > thank you very much > > thank you very much > > > > > > > >
> ------------------------ Yahoo! Groups Sponsor > >
> ---------------------~--> Sell a Home with Ease! > >
> http://us.click.yahoo.com/SrPZMC/kTmEAA/MVfIAA/dkFolB/TM > >
> ---------------------------------------------------------------------~
> > > -> > > > > To unsubscribe from this group, send an email to: > >
> EnergyPlus_Support-unsubscribe@y... > > > > The primary EnergyPlus web
> site is found at: > > http://www.energyplus.gov > > > > The group web
> site is: > > http://groups.yahoo.com/group/EnergyPlus_Support/ > > > >
> > > > > > > > > > > Your use of Yahoo! Groups is subject to > >
> http://docs.yahoo.com/info/terms/ > > > > > > > >
> ======================================================== > EnergyPlus
> Testing and Support      > EnergyPlus-Support@g...
> 
> 
> ------------------------ Yahoo! Groups Sponsor
> ---------------------~--> 4 DVDs Free +s&p Join Now
> http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/dkFolB/TM
> ---------------------------------------------------------------------~
> ->
> 
> To unsubscribe from this group, send an email to:
> EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx
> 
> The primary EnergyPlus web site is found at:
> http://www.energyplus.gov
> 
> The group web site is:
> http://groups.yahoo.com/group/EnergyPlus_Support/
> 
> 
> 
> 
> 
> 
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/ 
> 
> 



========================================================
EnergyPlus Testing and Support      
EnergyPlus-Support@xxxxxxxx


------------------------ Yahoo! Groups Sponsor ---------------------~-->
4 DVDs Free +s&p Join Now
http://us.click.yahoo.com/pt6YBB/NXiEAA/MVfIAA/dkFolB/TM
---------------------------------------------------------------------~->

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

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

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




 

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