Elena Guidolin's profile - activity

Dear all,

I am simulation a building using Openstudio and E+. The HVAC system is composted by a multifunctional heat pump (it makes simultaneously heating and cooling), a ground water condenser and cooled beams as air terminals that provided both the cooling and the heating in the zones. I have used the CentralHeatPumpSystem to simulate the multifunctional heat pump. I have used the PlantComponent:TemperatureSource to simulate the ground water used as condenser I have used the FourPipeInduction Air terminals to simulate the cooled beams. I can't understand why the simulation doesn't work properly and I have problems with the sizing of the objects and the convergence of the temperature.

Has someone of you any idea how should I do to solve this issue? I attach the idf below.

Thank you very much

Have a nice day

Elena

part of the error message:

************* Beginning System Sizing Calculations
************* Beginning Plant Sizing Calculations
** Warning ** In calculating the design coil UA for Coil:Cooling:Water HW CHW FOUR PIPE INDUCTION TERMINAL CHW CLG COIL 2
**   ~~~   ** the apparatus dew-point is below the coil design inlet water temperature;
**   ~~~   ** the coil outlet design conditions will be changed to correct the problem.
**   ~~~   ** The initial design conditions are: Tair,in = 25.9833
**   ~~~   **                                    Wair,in = 9.554298E-003
**   ~~~   **                                    Twater,in = 7.2200
**   ~~~   **                                    Tair,out = 9.2200
**   ~~~   **                                    Wair,out = 6.585921E-003
**   ~~~   ** The revised design conditions are: Tair,out = 9.2195
**   ~~~   **                                    Wair,out = 6.586107E-003
** Warning ** In calculating the design coil UA for Coil:Cooling:Water HW CHW FOUR PIPE INDUCTION TERMINAL CHW CLG COIL
**   ~~~   ** no apparatus dew-point can be found for the initial entering and leaving conditions;
**   ~~~   ** the coil outlet design conditions will be changed to correct the problem.
**   ~~~   ** The initial design conditions are: Tair,in = 25.9845
**   ~~~   **                                    Wair,in = 1.167724E-002
**   ~~~   **                                    Twater,in = 7.2200
**   ~~~   **                                    Tair,out = 9.2200
**   ~~~   **                                    Wair,out = 6.585921E-003
**   ~~~   ** The revised design conditions are: Tair,out = 9.2195
**   ~~~   **                                    Wair,out = 6.586107E-003
** Warning ** In calculating the design coil UA for Coil:Cooling:Water HW CHW FOUR PIPE INDUCTION TERMINAL CHW CLG COIL 1
**   ~~~   ** the apparatus dew-point is below the coil design inlet water temperature;
**   ~~~   ** the coil outlet design conditions will be changed to correct the problem.
**   ~~~   ** The initial design conditions are: Tair,in = 25.9901
**   ~~~   **                                    Wair,in = 9.862493E-003
**   ~~~   **                                    Twater,in = 7.2200
**   ~~~   **                                    Tair,out = 9.2200
**   ~~~   **                                    Wair,out = 6.585921E-003
**   ~~~   ** The revised design conditions are: Tair,out = 9.2195
**   ~~~   **                                    Wair,out = 6.586107E-003
** Warning ** In calculating the design coil UA for Coil:Cooling:Water HW CHW FOUR PIPE INDUCTION TERMINAL CHW CLG COIL 3
**   ~~~   ** the apparatus dew-point is below the coil design inlet water temperature;
**   ~~~   ** the coil outlet design conditions will be changed to correct the problem.
**   ~~~   ** The initial design conditions are: Tair,in = 25.9832
**   ~~~   **                                    Wair,in = 9.506870E-003
**   ~~~   **                                    Twater,in = 7.2200
**   ~~~   **                                    Tair,out = 9.2200
**   ~~~   **                                    Wair,out = 6.585921E-003
**   ~~~   ** The revised design conditions are: Tair,out = 9.2195
**   ~~~   **                                    Wair,out = 6.586107E-003
** Warning ** Controller:MechanicalVentilation = "CONTROLLER MECHANICAL VENTILATION 2", Zone="THERMAL ZONE5-1".
**   ~~~   ** No "PEOPLE" object has been specified in the ...

Dear all,

I am new with Openstudio. I am simulating a building conditioned by four pipe cooled beams. To do this I used HW CHW Four Pipe Induction Terminals. Modeling the system, I see that it works properly if I simulate a single zone with only one HW CHW Four Pipe Induction Terminal. If I do the same with more than one zone, it occours that the "Thermal Zone Exhaust Node List" has 2 nodes instead of one, as in my opinion it should be. Consequently these two fields are blank: " !- Induced Air Inlet Node Name" and " !- Air Inlet Node Name". If I go inside the IDF exported and I choose one of the two nodes and I fill these spaces it works properly.

This is the error I see running Openstudio: * Severe * IP: IDF line~31436 Error detected in Object=AIRTERMINAL:SINGLEDUCT:CONSTANTVOLUME:FOURPIPEINDUCTION, name=HW CHW FOUR PIPE INDUCTION TERMINAL 1 * ~~~ * Field [Induced Air Inlet Node Name] is required but was blank

This is the way that I fix it in EnergyPlus:

NodeList, Thermal Zone5-9 Exhaust Node List, !- Name !Node 238, !- Node Name 1
Node 214; !- Node Name 2

ZoneHVAC:AirDistributionUnit, HW CHW Four Pipe Induction Terminal 2 Air Distribution Unit, !- Name Node 210, !- Air Distribution Unit Outlet Node Name AirTerminal:SingleDuct:ConstantVolume:FourPipeInduction, !- Air Terminal Object Type HW CHW Four Pipe Induction Terminal 2; !- Air Terminal Name

AirTerminal:SingleDuct:ConstantVolume:FourPipeInduction, HW CHW Four Pipe Induction Terminal 2, !- Name , !- Availability Schedule Name Autosize, !- Maximum Total Air Flow Rate {m3/s} 2.5, !- Induction Ratio Node 213, !- Supply Air Inlet Node Name Node 214, !- Induced Air Inlet Node Name Node 210, !- Air Outlet Node Name , !- Hot Water Inlet Node Name , !- Cold Water Inlet Node Name Coil:Heating:Water, !- Heating Coil Object Type HW CHW Four Pipe Induction Terminal HW Htg Coil 2, !- Heating Coil Name , !- Maximum Hot Water Flow Rate {m3/s} 0, !- Minimum Hot Water Flow Rate {m3/s} 0.001, !- Heating Convergence Tolerance Coil:Cooling:Water, !- Cooling Coil Object Type HW CHW Four Pipe Induction Terminal CHW Clg Coil 2, !- Cooling Coil Name Autosize, !- Maximum Cold Water Flow Rate {m3/s} 0, !- Minimum Cold Water Flow Rate {m3/s} 0.001, !- Cooling Convergence Tolerance HW CHW Four Pipe Induction Terminal 2 Mixer; !- Zone Mixer Name

Coil:Heating:Water, HW CHW Four Pipe Induction Terminal HW Htg Coil 2, !- Name Always On Discrete 1, !- Availability Schedule Name Autosize, !- U-Factor Times Area Value {W/K} Autosize, !- Maximum Water Flow Rate {m3/s} Node 249, !- Water Inlet Node Name Node 250, !- Water Outlet Node Name Node 214, !- Air Inlet Node Name HW CHW Four Pipe Induction Terminal 2 Heating Coil Outlet, !- Air Outlet Node Name UFactorTimesAreaAndDesignWaterFlowRate, !- Performance Input Method Autosize, !- Rated Capacity {W} 82.2, !- Rated Inlet Water Temperature {C} 16.6, !- Rated Inlet Air Temperature {C} 71.1, !- Rated Outlet Water Temperature {C} 32.2, !- Rated Outlet Air Temperature {C} 0.5; !- Rated Ratio for Air and Water Convection

Anyone of u has an idea to fix this ... (more)