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District heating model with Dymola

Hello, I am trying to model the district heating from my university (UCD - Dublin). I have the demand data for 2015,206,2017 for all buildings that are part of the district. I have data on the boilers as well and the .mos file for the weather here in Dublin. However, my experience with Dymola/Modelica is VERY limited. I am trying to use the model: HeatingCoolingHotWater3Clusters as my starting point. This model is from the buildings master library. I was able to change the demand profiles for all the buildings and to load my weather file into the model. I also modified a little the model because it was considering a lake to cool down the water and we do not have this here in UCD.
the model is working almost fine, I have 9 buildings and if I consider 8 of them the model runs, however when I include my biggest load the model does not work. I keep getting this error:

Integration started at T = 0 using integration method LSODAR (Multi-step solver for stiff and non-stiff ODE's with root finder (lsodar of ODEPACK)) apa2.heaPum.port_a2.m_flow > -0.00013217641646749525 The following error was detected at time: 20226.39467644488 Model has flow reversal, but the parameter allowFlowReversal is set to false. m_flow_small = 0.000132176 ports[1].m_flow = -0.000132177

I tried to change the status of the heat pump of this building to TRUE, but I am still getting this error. Can anyone help me ? i have no idea how to solve it.

and if anyone has a better idea as a start point, I would appreciate any help. thanks

District heating model with Dymola

Hello, I am trying to model the district heating from my university (UCD - Dublin). I have the demand data for 2015,206,2017 for all buildings that are part of the district. I have data on the boilers as well and the .mos file for the weather here in Dublin. However, my experience with Dymola/Modelica is VERY limited. I am trying to use the model: HeatingCoolingHotWater3Clusters as my starting point. This model is from the buildings master library. I was able to change the demand profiles for all the buildings and to load my weather file into the model. I also modified a little the model because it was considering a lake to cool down the water and we do not have this here in UCD.
the model is working almost fine, I have 9 buildings and if I consider 8 of them the model runs, however when I include my biggest load the model does not work. I keep getting this error:

Integration started at T = 0 using integration method LSODAR (Multi-step solver for stiff and non-stiff ODE's with root finder (lsodar of ODEPACK)) apa2.heaPum.port_a2.m_flow > -0.00013217641646749525 The following error was detected at time: 20226.39467644488 Model has flow reversal, but the parameter allowFlowReversal is set to false. m_flow_small = 0.000132176 ports[1].m_flow = -0.000132177

I tried to change the status of the heat pump of this building to TRUE, but I am still getting this error. Can anyone help me ? i have no idea how to solve it.

and if anyone has a better idea as a start point, I would appreciate any help. thanks

District heating model with Dymola

Hello, I am trying to model the district heating from my university (UCD - Dublin). I have the demand data for 2015,206,2017 for all buildings that are part of the district. I have data on the boilers as well and the .mos file for the weather here in Dublin. However, my experience with Dymola/Modelica is VERY limited. I am trying to use the model: HeatingCoolingHotWater3Clusters as my starting point. This model is from the buildings master library. I was able to change the demand profiles for all the buildings and to load my weather file into the model. I also modified a little the model because it was considering a lake to cool down the water and we do not have this here in UCD.
the model is working almost fine, I have 9 buildings and if I consider 8 of them the model runs, however when I include my biggest load the model does not work. I keep getting this error:

Integration started at T = 0 using integration method LSODAR (Multi-step solver for stiff and non-stiff ODE's with root finder (lsodar of ODEPACK)) apa2.heaPum.port_a2.m_flow > -0.00013217641646749525 The following error was detected at time: 20226.39467644488 Model has flow reversal, but the parameter allowFlowReversal is set to false. m_flow_small = 0.000132176 ports[1].m_flow = -0.000132177

I tried to change the status of the heat pump of this building to TRUE, but I am still getting this error. Can anyone help me ? i have no idea how to solve it.

and if anyone has a better idea as a start point, I would appreciate any help. thanks