Alex Vlachokostas's profile - activity

@Xandrika Are you referring to the following object in EnergyPlus? Sizing:Parameters, 1.25, !- He

Hello everyone!

When I run a simulation through the EP idf editor I load the .idf file and the .epw file. My .idf already contains the .ddy data for NYC (it was given to me like that). However, when I run the simulation for a different location I only change the weather file (.epw file). I would like to change the .ddy file too so the idf file has the information for the new geographical location.

-How does EP work with the .ddy file of the weather file? -Should I copy and paste all the content of the .ddy file into the .idf file?

Thank you very much in advance.

Best regards, Alex Vlachokostas City College of New York -graduate student

Hi everyone, I currently have a Fan:ConstantVolume in a single thermal zone model: I want to change the Fan:ConstantVolume which does not cycle to a Fan:OnOff which cycles with heating/cooling. Therefore, after reading the InputOutput Reference document, I just substituted the Fan:ConstantVolume with the Fan:OnOff object.

However, I get the following severe error: * Severe * GetAirPathData: AirLoopHVAC = "SYS-1". * ~~~ * ..Invalid Air Loop Component Type = "FAN:ONOFF". * ~~~ * ..Air Loop Component Name = "SYS-1 SUPPLY FAN". * ~~~ * ..reference Branch = "SYS-1 MAIN BRANCH". * ~~~ * ...This component may only be referenced by a parent component such as AirLoopHVAC:Unitary:Furnace:HeatCool or similar. * Fatal * GetAirPathData: Errors found retrieving input for AirLoopHVAC.

Apparently there are more objects that I have to define. Any thoughts?

Thank you very much. I appreciate your help.

Alex

the command energyplus -w weather.epw -o out-test/ test.idf has a small typo. It should be: energyplus -w weather.epw -d

Output:Variable,*,Site Day Type Index,hourly;

I have 50 idf files and 50 weather files. Each idf file corresponds to a respective epw file. I don't want to simulate them one-by-one on EP launch. Would it be possible to write a script in order to run EP on each idf file with its respective weather file? If yes, what scripting language would you recommend? Are there any available examples?

Is there a way to report as an output variable the "day of week?" In my IDF the "Day of Week for Start Day" is a Thursday and I want to debug operation scheduling during specific days. For example, how can I quickly assess what day corresponds to 05/30? FYI: I tried formatting the cells in excel Home>date (custom date format) but that approach does not do the trick.

Perfect! Thank you very much @Aaron Boranian

output "day of week" Is there a way to report as an output variable the "day of week?" In my IDF the "Day of Week for St

output "day of week" Is there a way to report as an output variable the "day of week?" For example, in my IDF the "Day o

@adambgnr , @Archmage Does this mean that in order to change the PV output (in the GeneratoswithPV.idf example file) I w

I am trying to simulate in OpenStudio (OS) a similar version of the SolarCollectorFlatPlateWater.idf, example file in E+, using the available OS components. The idf example file is an active direct system (meaning there is no heat exchanger involved. The water itself picks up thermal energy from the collectors and goes to the storage tank).

In contrast, I want to add a heat exchanger component (i.e., make it an active indirect system). I have identified which components to use as shown at the attached images. More specifically, the following image shows the Supply side (which is a solar collector and a pump) and the Demand side (which is a fluid-to-fluid heat exchanger and storage tank -modeled with the WaterHeater:Mixed object-). Then the next image shows the Supply side (which is a fluid-to-fluid heat exchanger and storage tank) and the Demand side (which is an auxiliary water heater-modeled again with the WaterHeater:Mixed object-).

Am I missing any outstanding OS components in the modeling workflow? Of course, the HVAC system of the building is something different and it is modeled apart. I am still far away from just hitting the 'Run' simulation button and troubleshooting the model so any tips are very welcomed and appreciated.

I tried the DCV in two different OS/E+ files. I can now see the Output:Variable,*,Air System Outdoor Air Mass Flow Rate,Hourly; changing when I use the DCV option.

@Julien Marrec I report the Output:Variable,*,Air System Outdoor Air Mass Flow Rate,hourly; and Output:Variable,*,Fan Electric Energy,hourly; but I don't see any differences with or without the DCV. Apparently, I am doing something wrong. Any recommendations for which other outputs to report in order to continue testing my DCV configuration? The I/OReference does not give any output examples.

Just some thoughts:

-The BCL places the Daylight Sensor at the center of the room (as its name implies). Maybe your room is too deep and the window size is small. Therefore a daylight control in the middle of the room might work to your disadvantage. The daylight sensor keeps trying to meet the 45 fc target and as a result, it overworks the electric lights.

-The OS daylight sensor has a horizontal arrow which should be pointing to the window and a vertical arrow that should be pointing up.

-Action items: Change the location of the daylight control to a one closer to the window. Also try: 1, ! Lighting Control type.

Hope that helps.

I want to create a script in order to take an epw file, process it, and then convert it back to epw. The reason for writing a script is because I want to process the epw file 500 times and as a result create 500 new epw files. Until now I was 'brewing on a small scale' using the weather converter program to convert the epw to csv, then process it in excel, and at the end convert it back to epw. Any suggestions on scaling up?

@mleah I had the same error. Oddly enough, I did not have any glycol fluid type in my system. Although it might seem unrelated... what fixed the problem in my model was correcting the fileds at the WaterHeater:Mixed object. My model had a Solar Tank Storage and a Instantaneous/Tankless system. Both are modeled as WaterHeater:Mixed objects but for the Solar Tank Storage system the !- Heater Maximum Capacity {W} field should be 0 and for the Instantaneous/Tankless system the !- Heater Maximum Capacity {W} field should be 845000. There is a similar question on unmet hours here

@RChidwick I had the same error. Oddly enough, I did not have any glycol fluid type in my system. Although it might seem unrelated... what fixed the problem in my model was correcting the fileds at the WaterHeater:Mixed object. My model had a Solar Tank Storage and a Instantaneous/Tankless system. Both are modeled as WaterHeater:Mixed objects but for the Solar Tank Storage system the !- Heater Maximum Capacity {W} filed should be 0 and for the Instantaneous/Tankless system the !- Heater Maximum Capacity {W}field should be 845000

Thank you @Jamie Bull for the code example! Extremely helpful!

Thank you @__AmirRoth__ !

I want to dynamically assign the Vertex values of the following surface

Shading Surface 1, !- Name , !- Transmittance Schedule Name , !- Number of Vertices 0, 2.5, 4.572, !- X,Y,Z Vertex 1 {m} 0, 0, 4.572, !- X,Y,Z Vertex 2 {m} 1.22, 0, 4.572, !- X,Y,Z Vertex 3 {m} 1.22, 2.5, 4.572; !- X,Y,Z Vertex 4 {m}

based on some calculations that include the latitude of the site.

Site:Location, Tampa International Ap, !- Name 27.97, !- Latitude {deg} -82.53, !- Longitude {deg} -5, !- Time Zone {hr} 6; !- Elevation {m}

I would like to call the 27.97 latitude value. Any tips? The following example is useful but not exactly what I am looking for: Group Parametrics

Thank you.

Step 1) Picking up a random example file from EnergyPlus in order to better explain the solution (e.g., 1ZoneDataCenterCRAC_wPumpedDXCoolingCoil.idf) you will see that the roof is under the following object:

BuildingSurface:Detailed,
Zn001:Roof001,           !- Name
Roof,                    !- Surface Type
ROOF31,                  !- Construction Name
Main Zone,               !- Zone Name
Outdoors,                !- Outside Boundary Condition
,                        !- Outside Boundary Condition Object
SunExposed,              !- Sun Exposure
WindExposed,             !- Wind Exposure
0,                       !- View Factor to Ground
4,                       !- Number of Vertices
0.000000,15.24000,4.572,  !- X,Y,Z ==> Vertex 1 {m}
0.000000,0.000000,4.572,  !- X,Y,Z ==> Vertex 2 {m}
15.24000,0.000000,4.572,  !- X,Y,Z ==> Vertex 3 {m}
15.24000,15.24000,4.572;  !- X,Y,Z ==> Vertex 4 {m}

Step 2) ROOF31 is your roof's construction name. The object consists only of R31LAYER.

Construction,
ROOF31,                  !- Name
R31LAYER;                !- Outside Layer

Step 3) You have to look for the R31LAYER object. The answer is:

Material:NoMass,
R31LAYER,                !- Name
Rough,                   !- Roughness
5.456,                   !- Thermal Resistance {m2-K/W}
0.9000000,               !- Thermal Absorptance
0.7500000,               !- Solar Absorptance
0.7500000;               !- Visible Absorptance

This is where your solar and visible absorptance values are.