Ahmad's profile - activity

Keigo, well noted. I thank you very much !

How can I explain such decrease in pumps consumption starting October (which shows very small values) till March, compar

Here is the file: https://www.dropbox.com/s/56r20jpxhh3l6dm/Final%20Model%20Calibration%20to%20send.osm?dl=0

Thanks Keigo. Would you like me to provide you with my model separately ? If yes, how can I remove the simulation run in

The tables here are summary for the yearly performance: https://www.dropbox.com/s/85cybu9qxg5xty9/Unmet%20Hours.PNG?dl=0

Ah for the plant loop, I have changed it. I removed the fluid to fluid heat exchanger and left only one pump. See here:

I'v done the simulation before with pumps electricity. I have the graph shown here in the link: https://www.dropbox.com/

What is the best way to check if it is running for 24 hours ? Also considering the pumps results like this, can they be

Thanks Keigo ! Both pumps are variable speed pumps. The hot water pump head is 198043 Pa and the chilled water pump head

Interpreting low pumps consumption/demand and heat rejection Hi all, In my building model, I have a boiler hot water lo

Interpreting low pumps consumption/demand and heat rejection Hi all, In my building model, I have a boiler hot water lo

I also just want to finalize that I was thinking of an idea related to personalized cooling. How do you think I can inte

Also last question, for the variable speed pumps I have defined in Openstudio for the water loops, which parameters do y

Thanks a lot ! All the lamps in the building are of LED type installed in 2016. Their details are in the link here: htt

Thank you ! The boiler I have unfortunately provides about 4-5 buildings in reality so in Openstudio I modeled it as Au

Energy Conservation during Unoccupied Hours Hi, I'm using Openstudio to implement energy conservation measures to my bu

Greetings,

I've defined 1 indirect absorption chiller loop and 1 condenser loop in my Openstudio model and I have configured it to be running in the summer for cold water to be provided to cooling coils.

When simulating my model, I am getting high pumps energy consumption during this period, which seem unreasonable. A plot of the mass flow rates for the chiller and condenser pumps is shown below:

There seems to be very high values for the condenser pump (about 80 kg/s) compared to the chiller pump (about 4-6 kg/s). Both are Variable Speed Pumps and working intermittent.

Could anyone assist me to solve this issue of high pumps energy consumption ? I can provide my model files if needed upon request.

Thank you.

Cody, thanks a lot !

Ok Cody, thanks. On another note, as you see that I have defined the cooling through the steam operated chiller. In the

For Meter=Steam:Facility [J], ResourceType=Steam, contents are: INDIRECT ABSORPTION CHILLER:Chiller Source Steam Energ

Hi Cody, thanks ! 1) Where can I find a clear definition for the Design Loop Exit Temp and Loop Design Temp. Difference

Hi Cody. It would be great to get your feedback when you can. Thanks !

Cont. writing: Simulating with the above parameters yields more reasonable results as found in the link here: https:/

Cont. writing: Simulating with the above parameters yields more reasonable results as found in the link here: https:/

Hi Cody, thanks ! I went with the robust way and worked with the loops parameters: DLET: The Design Loop Exit Temp. DIW

Ah ok, great. Could you let me know if you can spare a few minutes to see my model and give me your thoughts on it ? I c

Thanks Cody, I'll manage to alter this and get back here with any changes. Could you just elaborate on the dT parameter

The basic idea started from results showing high pump power consumption throughout the summer period which should be fro

Hi Cody, thanks for the reply. Yes, I am auto-sizing. I took a look at the EIO file and here is what is inside: "Desig

High Pump Energy Consumption Greetings, I've defined 1 indirect absorption chiller loop and 1 condenser loop in my Open

Modeling Personal Cooling Fans Hi, Looking into methods of reducing energy consumption of an office building I have mod

No cooling load when using absorption chiller Greetings, I'm using a steam absorption chiller for an offices building f

Hello team, Hope to get any feedback from you here. Thanks.

Cooling/Heating Thermostat Schedule Hello team, I have modeled my building in Openstudio and would like to assign cooli

HVAC autosizing using my schedule or summer/winter design days Hi team, Good day. In the "weather file and design days

Hello,

Good day to all.

I am modeling an HVAC system for an offices building with 8 floors which has several AHUs and FCUs installed. The simulation stops with the following error (Copied as is):

   ** Severe  ** Plant temperatures are getting far too hot, check controls and relative loads and capacities
   **   ~~~   ** PlantLoop Name (DemandSide)= HOT WATER LOOP
   **   ~~~   ** PlantLoop Setpoint Temperature=67.0 {C}
   **   ~~~   ** PlantLoop Inlet Node (SupplySide) does not have a Setpoint.
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) does not have a Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (SupplySide) has a Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (DemandSide) does not have a Setpoint.
   **   ~~~   ** PlantLoop Outlet Node (DemandSide) "NODE 134" has temperature=300.1 {C}
   **   ~~~   ** PlantLoop Inlet Node (DemandSide) "NODE 133" has temperature=300.2 {C}
   **   ~~~   ** PlantLoop Minimum Temperature=0.0 {C}
   **   ~~~   ** PlantLoop Maximum Temperature=100.0 {C}
   **   ~~~   ** PlantLoop Flow Request (SupplySide)=6.9 {kg/s}
   **   ~~~   ** PlantLoop Flow Request (DemandSide)=0.6 {kg/s}
   **   ~~~   ** PlantLoop Node (DemandSide) "NODE 134" has mass flow rate =0.6 {kg/s}
   **   ~~~   ** PlantLoop PumpHeat (SupplySide)=1982.2 {W}
   **   ~~~   ** PlantLoop PumpHeat (DemandSide)=185.5 {W}
   **   ~~~   ** PlantLoop Cooling Demand=6855817.6 {W}
   **   ~~~   ** PlantLoop Heating Demand=0.0 {W}
   **   ~~~   ** PlantLoop Demand not Dispatched=0.0 {W}
   **   ~~~   ** PlantLoop Unmet Demand=-6855817.6 {W}
   **   ~~~   ** PlantLoop Capacity=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (SupplySide)=411062.5 {W}
   **   ~~~   ** PlantLoop Capacity (DemandSide)=0.0 {W}
   **   ~~~   ** PlantLoop Operation Scheme=HOT WATER LOOP OPERATION SCHEMES
   **   ~~~   ** PlantLoop Operation Dispatched Load = 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (SupplySide)= 0.0 {W}
   **   ~~~   ** PlantLoop Operation Dispatched Load (DemandSide)= 0.0 {W}

I read the other posts asking questions related to what I am asking too but I wasn't able to locate the problem.

The following are photos for the supply/demand of the loop (There are a lot of heating coils so I took two screenshots showing the essentials):

The outlet node supply side set point is set to 80 C. The pumps are intermittent. Both AHUs and FCUs coils inlet water temperatures are set to 80 C and outlet water temperatures to 69 C. The AHUs coils capacities range between 5 kw to 10 kw (I have about 11 coils for the AHUs). The boiler design flow rate is auto-sized. The plant design loop exit temperature is 80 C and loop design temperature difference is 11 C.

I can't seem to solve my problem. Can you assist ?

Many thanks in advance.

Thanks Julien, it worked as you stated !