From c06ac4fd8048f0987e9f8d29961e1f2aa8c82b75 Mon Sep 17 00:00:00 2001 From: Michael Wetter Date: Tue, 7 Oct 2014 16:37:20 -0700 Subject: [PATCH] Changed slab to use eps-NTU by default This is for #290. For the FLEXLAB model, computing time is 4 times lower with this configuration --- .../HeatExchangers/RadiantSlabs/Examples/StepResponse.mo | 5 +++-- .../HeatExchangers/RadiantSlabs/ParallelCircuitsSlab.mo | 4 ++-- .../Fluid/HeatExchangers/RadiantSlabs/SingleCircuitSlab.mo | 3 ++- 3 files changed, 7 insertions(+), 5 deletions(-) diff --git a/Buildings/Fluid/HeatExchangers/RadiantSlabs/Examples/StepResponse.mo b/Buildings/Fluid/HeatExchangers/RadiantSlabs/Examples/StepResponse.mo index f8373400e48..5101ddb92c1 100644 --- a/Buildings/Fluid/HeatExchangers/RadiantSlabs/Examples/StepResponse.mo +++ b/Buildings/Fluid/HeatExchangers/RadiantSlabs/Examples/StepResponse.mo @@ -28,8 +28,9 @@ model StepResponse "Model that tests the radiant slab" sysTyp=Buildings.Fluid.HeatExchangers.RadiantSlabs.BaseClasses.Types.SystemType.Floor, disPip=0.2, A=A, - energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) - "Slabe with embedded pipes" + energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, + nSeg=10, + use_epsilon_NTU=false) "Slabe with embedded pipes" annotation (Placement(transformation(extent={{10,-30},{30,-10}}))); parameter Modelica.SIunits.MassFlowRate m_flow_nominal= diff --git a/Buildings/Fluid/HeatExchangers/RadiantSlabs/ParallelCircuitsSlab.mo b/Buildings/Fluid/HeatExchangers/RadiantSlabs/ParallelCircuitsSlab.mo index 42f9a0b785b..c7713ff3354 100644 --- a/Buildings/Fluid/HeatExchangers/RadiantSlabs/ParallelCircuitsSlab.mo +++ b/Buildings/Fluid/HeatExchangers/RadiantSlabs/ParallelCircuitsSlab.mo @@ -21,7 +21,7 @@ model ParallelCircuitsSlab m_flow_small=m_flow_small/nCir)); parameter Integer nCir(min=1) = 1 "Number of parallel circuits"; - parameter Integer nSeg(min=1) = 10 + parameter Integer nSeg(min=1) = 1 "Number of volume segments in each circuit (along flow path)"; parameter Modelica.SIunits.Area A @@ -45,7 +45,7 @@ model ParallelCircuitsSlab parameter Boolean homotopyInitialization = true "= true, use homotopy method" annotation(Evaluate=true, Dialog(tab="Advanced")); - parameter Boolean use_epsilon_NTU = false + parameter Boolean use_epsilon_NTU = true "Set to true to use an epsilon-NTU model for the heat conduction" annotation(Dialog(tab="Advanced")); diff --git a/Buildings/Fluid/HeatExchangers/RadiantSlabs/SingleCircuitSlab.mo b/Buildings/Fluid/HeatExchangers/RadiantSlabs/SingleCircuitSlab.mo index d78ca2cfd88..80c6478ceb1 100644 --- a/Buildings/Fluid/HeatExchangers/RadiantSlabs/SingleCircuitSlab.mo +++ b/Buildings/Fluid/HeatExchangers/RadiantSlabs/SingleCircuitSlab.mo @@ -2,6 +2,7 @@ within Buildings.Fluid.HeatExchangers.RadiantSlabs; model SingleCircuitSlab "Model of a single circuit of a radiant slab" extends Buildings.Fluid.HeatExchangers.RadiantSlabs.BaseClasses.Slab; extends Buildings.Fluid.FixedResistances.BaseClasses.Pipe( + nSeg=1, final diameter=pipe.dIn, length=A/disPip, final thicknessIns=0, @@ -21,7 +22,7 @@ model SingleCircuitSlab "Model of a single circuit of a radiant slab" parameter Modelica.SIunits.Area A "Surface area of radiant slab" annotation(Dialog(group="Construction")); - parameter Boolean use_epsilon_NTU = false + parameter Boolean use_epsilon_NTU = true "Set to true to use an epsilon-NTU model for the heat conduction" annotation(Dialog(tab="Advanced"));