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2023-03-07 20:01:49 -0500 | asked a question | cove tool Exposed Floor cove tool Exposed Floor Hi everybody - does anyone know if cove tool properly model an exposed floor as seen in a cantil |
2023-03-07 20:00:16 -0500 | commented answer | Sketchbox Exposed Floor Thanks Drew! :) |
2023-03-07 19:59:54 -0500 | marked best answer | Sketchbox Exposed Floor Hello - I have a sketchbox question. If I build a sketchbox model that ends up with some kind of exposed floor because the 2fl is larger than the 1st floor, is the tool modeling that exposed floor as I would expect? Thanks! |
2023-02-27 20:28:01 -0500 | edited question | Sketchbox Exposed Floor Sketchbox Exposed Floor Hello - I have a sketchbox question. If I build a sketchbox model that ends up with some kind o |
2023-02-27 20:27:44 -0500 | commented answer | Sketchbox Exposed Floor Thanks Drew, I mean the situation where you have two "shells" stacked on top of each other, see picture I added in the o |
2023-02-23 23:43:58 -0500 | asked a question | Sketchbox Exposed Floor Sketchbox Exposed Floor Hello - I have a sketchbox question. If I build a sketchbox model that ends up with some kind o |
2023-02-13 12:07:10 -0500 | asked a question | Modelica DES Control Loop Parameters Modelica DES Control Loop Parameters Hi, I am hoping for some more detailed advice for control loop settings in Distric |
2023-02-13 11:36:12 -0500 | commented answer | Modelica Cooling Tower Energy Balance Thanks Michael. Yeah the issue was definitely related to the control loop settings |
2023-01-02 12:09:43 -0500 | marked best answer | Modelica Cooling Tower Energy Balance Hello, I am running a District Energy System in Modelica/Dymola using the geojson to modelica translator and Modelica buildings library. My model has 150 buildings attached to the District HW and CHW loops. I am having an issue with cooling plant operation. Whenever the cooling plant is enabled, I get massive reduction in Integrator time step. I have traced the issue down to the calculation of energy balance for the fluid volume inside the cooling tower. From what I can tell, the solver hits major errors whenever the value of the energy balance in the cooling tower fluid volume changes significantly. The strongest driver of changes to the energy balance is the outside air temperature. I cannot figure out how to deal with this issue... theres nothing I can do the reduce the oscillations in outside air temperature. How can I reduce the sensitivity of the energy balance equation to these changes? Thanks, Graham |
2023-01-02 12:09:29 -0500 | answered a question | Modelica Cooling Tower Energy Balance I think I figured out a solution - I decreased the solver's error tolerance from 1e-3 to 1e-6 per the recommendations fr |
2023-01-02 12:09:29 -0500 | received badge | ● Rapid Responder (source) |
2023-01-01 20:27:41 -0500 | asked a question | Modelica Cooling Tower Energy Balance Modelica Cooling Tower Energy Balance Hello, I am running a District Energy System in Modelica/Dymola using the geojson |
2022-12-21 17:32:21 -0500 | commented answer | Modelica District Heating Heat Pump Thank you Michael! |
2022-12-21 17:32:11 -0500 | marked best answer | Modelica District Heating Heat Pump Hello, I am working on a Modelica model of a District Energy System built using the geojson to modelica translator. I am hoping for some advice on a modification I would like to make. The GMT builds a district energy system with a Central Heating Plant (boiler) and Central Cooling Plant (chiller). I would like to switch the heating plant to use a heat pump and also use the resulting cool evaporator fluid to do some "shared" cooling for the chilled water loop. Anyway it looks like I can do this using the Heat Pump Heat Exchanger component as provided in the Modelica Buildings library. I think I should probably use the component by placing it inside the Central Heating Plant and basically replacing the boiler components. I would also need to bring in the chilled water return to make this work. Is this a good plan? Is there a simpler way to achieve what I want? I didn't find any other components that seemed like a good fit for my needs. Thanks! Graham |
2022-12-20 13:41:43 -0500 | received badge | ● Enthusiast |
2022-12-19 22:05:48 -0500 | asked a question | Modelica District Heating Heat Pump Modelica District Heating Heat Pump Hello, I am working on a Modelica model of a District Energy System built using the |
2022-12-19 22:02:36 -0500 | marked best answer | Speed up Modelica DES Models Hi, I am building a large district energy model (150 buildings) using the modelica buildings library and the geojson to modelica translator in Dymola. Does anyone have any tips for speeding up the simulation? I tried setting it to parallelize (Advanced.ParallelizeCode = true) but I got a bunch of errors. Thanks! Graham |
2022-12-19 22:02:34 -0500 | received badge | ● Commentator |
2022-12-19 22:02:34 -0500 | commented answer | Speed up Modelica DES Models Very good advice here, thanks! |
2022-12-18 11:41:43 -0500 | asked a question | Speed up Modelica DES Models Speed up Modelica DES Models Hi, I am building a large district energy model (150 buildings) using the modelica buildin |
2022-12-08 10:17:56 -0500 | marked best answer | Modelica power consumption outputs Hi All, I am implementing a district heating system using the UrbanOpt geojson-modelica translator. Is there a tutorial or explainer for how to get outputs setup for chiller power consumption, boiler energy consumption, pump energy consumption, etc? I want to get outputs that would let me calculate the end uses and total power consumption of the district system. I am using OpenModelica. Thanks, Graham |
2022-12-08 10:17:49 -0500 | commented answer | Modelica power consumption outputs Awesome, thank you!! |
2022-12-06 18:09:46 -0500 | asked a question | Modelica power consumption outputs Modelica power consumption outputs Hi All, I am implementing a district heating system using the UrbanOpt geojson-model |
2022-10-14 15:06:31 -0500 | edited answer | UrbanOpt DES Example Project On the advice on an NREL developer I tried to do the same thing but in a pure Linux environment (I used the Windows Subs |
2022-10-14 15:05:46 -0500 | edited answer | UrbanOpt DES Example Project On the advice on an NREL developer I tried to do the same thing but in a pure Linux environment (I used the Windows Subs |
2022-10-14 15:05:11 -0500 | answered a question | UrbanOpt DES Example Project On the advice on an NREL developer I tried to do the same thing but in a pure Linux environment (Imused the Windows Subs |
2022-10-10 18:53:18 -0500 | asked a question | UrbanOpt DES Example Project UrbanOpt DES Example Project Hi Everyone - hoping there is someone from NREL on the UrbanOpt DES team that might see thi |
2022-10-10 18:53:12 -0500 | asked a question | UrbanOpt DES Example Project UrbanOpt DES Example Project Hi Everyone - hoping there is someone from NREL on the UrbanOpt DES team that might see thi |
2022-05-06 10:08:55 -0500 | commented question | Upgrade OS App from 1.2.0 to 1.3.0 - temperature issue Thanks Julien. I've discovered a bunch of issues my geometry, once those are resolved I will try doing the upgrade again |
2022-04-14 17:41:36 -0500 | asked a question | Upgrade OS App from 1.2.0 to 1.3.0 - temperature issue Upgrade OS App from 1.2.0 to 1.3.0 - temperature issue Hi All, Just tried running a model in OS Application 1.3.0 that |
2021-12-15 13:37:58 -0500 | commented answer | Parametric Analysis tool local server slow Ah ha, thank you! |
2021-12-15 13:37:33 -0500 | marked best answer | Parametric Analysis tool local server slow Hi All, I've been trying out the OpenStudio PAT. When I first open up the program and run an analysis set using the local server it takes a looong time, at least 5 minutes, to get through the "Starting Server" dialog. Once it has finished an initial run all subsequent runs are faster but every time I launch PAT it is annoying to have to do this very long initial run. Any ideas? It doesn't appear there are that many settings to tweak, at least in the regular PAT UI or the web interface. Thanks, Graham |
2021-12-13 15:42:47 -0500 | edited question | Parametric Analysis tool local server slow Parametric Analysis tool local server slow Hi All, I've been trying out the OpenStudio PAT. When I first open up the pr |
2021-12-13 15:42:15 -0500 | asked a question | Parametric Analysis tool local server slow Parametric Analysis tool local server slow Hi All, I've been trying out the OpenStudio PAT. When I first open up the pr |
2021-12-02 15:35:01 -0500 | commented answer | OpenStudio Crash Remove Thermal Zone Equipment Thanks David. I did as you suggested and now it opens without crashing. |
2021-12-02 11:08:53 -0500 | answered a question | OpenStudio Crash Remove Thermal Zone Equipment OK I figured it out It seems I had one Zone Equipment List that was configured in a way that OpenStudio crashed when I |
2021-12-02 11:08:53 -0500 | received badge | ● Rapid Responder (source) |
2021-12-01 18:21:37 -0500 | edited question | OpenStudio Crash Remove Thermal Zone Equipment OpenStudio Crash Remove Thermal Zone Equipment Hi, I'm having a lot of trouble changing out the HVAC system in this mod |
2021-12-01 18:20:51 -0500 | edited question | OpenStudio Crash Remove Thermal Zone Equipment OpenStudio Crash Remove Thermal Zone Equipment Hi, I'm having a lot of trouble changing out the HVAC system in this mod |
2021-12-01 18:20:05 -0500 | edited question | OpenStudio Crash Remove Thermal Zone Equipment OpenStudio Crash Remove Thermal Zone Equipment Hi, I'm having a lot of trouble changing out the HVAC system in this mod |