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Re: [EnergyPlus_Support] Re: Plant Loop Setting



I am sorry that I did not read the original question more closely.  In 
EnergyPlus setpoints are propogated on the supply side of a plant loop, but 
there is no need for setpoints on the demand side of a plant loop.  And in air 
loops, setpoints are only valid at nodes that need them.  So, it is normal that 
the demand side does not show valid setpoints.  They are not used to control 
the baseboard heater.

Mike


On 25 Sep 2006 at 13:56, natasamdj wrote:

> Dear Michael,
> I posted my files in EPSupport_BaseboardModel.zip and with the 
> explanation "Baseboar Heater Model and Plant Loop Control". I could 
> not find where is the wrong in my files. I am sending to you three 
> files *.idf, all of them more or less similar. In addition I am 
> sending to you a doc file, with the explanation what about I am 
> wondering.
> 
> Please, help to me with your answer or adivece.
> 
> Thank you in advance!
> 
> Natasa M.Djuric
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Michael J. Witte" 
> <mjwitte@...> wrote:
> >
> > 1.  Baseboard Heater:Water:Convective is intended to model 
> thermostatically 
> > controlled baseboard heat.  The model is not controlling return 
> water 
> > temperature, rather it is controlling the water flow rate to add 
> the required 
> > amount of heat to the zone to meet the thermostat setpoint.  There 
> is not a 
> > direct way to model uncontrolled baseboard with varying supply 
> temperature.  
> > The way to make the baseboard always run at full flow is to set 
> the thermostat 
> > setting very high.  You should then see full flow whenever the 
> system is on, 
> > but the heat output and suppy-return deltaT should vary as the 
> supply 
> > temperature varies.
> > 
> > 2.  Check the setpoint schedule definition.  There should be no 
> difference in 
> > setpoint operation between design days and other days.  If you 
> cannot see the 
> > problem in the schedule definition, then please sumbit the file 
> (zipped) to the 
> > files are of the yahoo group or e-mail to energyplus-support@...
> > 
> > Mike
> > 
> > 
> > On 19 Sep 2006 at 12:37, natasamdj wrote:
> > 
> > > Dear,
> > > I have two questions about the Plant Loop settings. I have made 
> a 
> > > model with the Baseboard Heater: Water: Convective. In addition 
> I 
> > > have the real data, and I would like to adjust the simulation 
> output 
> > > with these real-life data.
> > > 1. I set the Loop Temperature Setpoint by using Set Point 
> Manager: 
> > > Outside Air. I found out in the output that E+ calculated the 
> load 
> > > so that water mass flow rate has been increased how the Loop 
> > > Temperature is lower. In other words, how the outdoor 
> temperature 
> > > increases, the supply water temperature is decreased, and the 
> water 
> > > flow is increased. I have some real data, and I would like to 
> > > combine that with the simulation results. Actually, I found out 
> that 
> > > E+ calculated almost the same return temperature for the 
> different 
> > > outdoor temperatures, while the supply temperature is decreased. 
> > > Because of that the water flow has been increased all the time 
> how 
> > > the outdoor temperature is increased. How I can model different 
> > > managing of the return temperature? Is it possible to model that 
> the 
> > > difference between the supply and return water temperature is 
> > > constant (or almost) constant for the different outdoor 
> conditions?
> > > 2. I found in the report output, that System Node Setpoint Temp 
> for 
> > > the demand side is calculated only for the design day, while for 
> the 
> > > other days it is zero (0). In this case the System Node Setpoint 
> > > Temp for Demand side should be calculated regarding to Set Point 
> > > Manager: Outside Air, and it is calculated exactly by this 
> schema 
> > > but only for the design day. In addition, the System Node 
> Setpoint 
> > > Temp is calculated correctly for all the nodes at Supply side, 
> but 
> > > not for the nodes at Demand side. What should I do to get these 
> > > temperatures correctly for all other days at Demand side nodes?
> > > 
> > > If it is necessary I can send to my *.idf file.
> > > 
> > > Thank you in advance!
> > > 
> > > Natasa M.Djuric 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 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.
> > > 
> > > EnergyPlus Documentation is searchable.  Open EPlusMainMenu.idf 
> and press the
> > > "search" button.
> > >  
> > > Yahoo! Groups Links
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > 
> > 
> > ========================================================
> > Michael J. Witte, GARD Analytics, Inc.
> > EnergyPlus Testing and Support      
> > EnergyPlus-Support@...
> >
> 
> 
> 
> 
> 
> 
> 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.
> 
> EnergyPlus Documentation is searchable.  Open EPlusMainMenu.idf and press the
> "search" button.
>  
> Yahoo! Groups Links
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 


========================================================
Michael J. Witte, GARD Analytics, Inc.
EnergyPlus Testing and Support      
EnergyPlus-Support@xxxxxxxx





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