Modelica.Thermal.FluidHeatFlow.Components

Basic components (pipes, valves)

Information

This package contains components:

pipe without heat exchange
pipe with heat exchange
valve (simple controlled valve)

Pressure drop is taken from partial model SimpleFriction.
Thermodynamic equations are defined in partial models (package Partials).

Main Authors:

Anton Haumer
Technical Consulting & Electrical Engineering
A-3423 St.Andrae-Woerdern, Austria
email: a.haumer@haumer.at

Dr. Christian Kral
Austrian Institute of Technology, AIT
Giefinggasse 2
A-1210 Vienna, Austria

This Modelica package is free software and the use is completely at your own risk; it can be redistributed and/or modified under the terms of the Modelica License 2. For license conditions (including the disclaimer of warranty) see Modelica.UsersGuide.ModelicaLicense2 or visit https://www.modelica.org/licenses/ModelicaLicense2.

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name	Description
IsolatedPipe	Pipe without heat exchange
HeatedPipe	Pipe with heat exchange
Valve	Simple valve

Modelica.Thermal.FluidHeatFlow.Components.IsolatedPipe

Pipe without heat exchange

Information

Pipe without heat exchange.
Thermodynamic equations are defined by Partials.TwoPortMass(Q_flow = 0).
Note: Setting parameter m (mass of medium within pipe) to zero leads to neglection of temperature transient cv*m*der(T).

Extends from Interfaces.Partials.TwoPort (Partial model of two port), Interfaces.Partials.SimpleFriction (Simple friction model).

Parameters

Name Description

medium Medium in the component

m Mass of medium [kg]

T0 Initial temperature of medium [K]

T0fixed Initial temperature guess value or fixed

tapT Defines temperature of heatPort between inlet and outlet temperature

h_g Geodetic height (height difference from flowPort_a to flowPort_b) [m]

Simple Friction

V_flowLaminar Laminar volume flow [m3/s]

dpLaminar Laminar pressure drop [Pa]

V_flowNominal Nominal volume flow [m3/s]

dpNominal Nominal pressure drop [Pa]

frictionLoss Part of friction losses fed to medium

Name	Description
medium	Medium in the component
m	Mass of medium [kg]
T0	Initial temperature of medium [K]
T0fixed	Initial temperature guess value or fixed
tapT	Defines temperature of heatPort between inlet and outlet temperature
h_g	Geodetic height (height difference from flowPort_a to flowPort_b) [m]
Simple Friction
V_flowLaminar	Laminar volume flow [m3/s]
dpLaminar	Laminar pressure drop [Pa]
V_flowNominal	Nominal volume flow [m3/s]
dpNominal	Nominal pressure drop [Pa]
frictionLoss	Part of friction losses fed to medium

Connectors

Name Description

flowPort_a

flowPort_b

Name	Description
flowPort_a
flowPort_b

Modelica.Thermal.FluidHeatFlow.Components.HeatedPipe

Pipe with heat exchange

Information

Pipe with heat exchange.
Thermodynamic equations are defined by Partials.TwoPort.
Q_flow is defined by heatPort.Q_flow.
Note: Setting parameter m (mass of medium within pipe) to zero leads to neglection of temperature transient cv*m*der(T).
Note: Injecting heat into a pipe with zero massflow causes temperature rise defined by storing heat in medium's mass.

Extends from Interfaces.Partials.TwoPort (Partial model of two port), Interfaces.Partials.SimpleFriction (Simple friction model).

Parameters

Name Description

medium Medium in the component

m Mass of medium [kg]

T0 Initial temperature of medium [K]

T0fixed Initial temperature guess value or fixed

tapT Defines temperature of heatPort between inlet and outlet temperature

h_g Geodetic height (heigth difference from flowPort_a to flowPort_b) [m]

Simple Friction

V_flowLaminar Laminar volume flow [m3/s]

dpLaminar Laminar pressure drop [Pa]

V_flowNominal Nominal volume flow [m3/s]

dpNominal Nominal pressure drop [Pa]

frictionLoss Part of friction losses fed to medium

Name	Description
medium	Medium in the component
m	Mass of medium [kg]
T0	Initial temperature of medium [K]
T0fixed	Initial temperature guess value or fixed
tapT	Defines temperature of heatPort between inlet and outlet temperature
h_g	Geodetic height (heigth difference from flowPort_a to flowPort_b) [m]
Simple Friction
V_flowLaminar	Laminar volume flow [m3/s]
dpLaminar	Laminar pressure drop [Pa]
V_flowNominal	Nominal volume flow [m3/s]
dpNominal	Nominal pressure drop [Pa]
frictionLoss	Part of friction losses fed to medium

Connectors

Name Description

flowPort_a

flowPort_b

heatPort

Name	Description
flowPort_a
flowPort_b
heatPort

Modelica.Thermal.FluidHeatFlow.Components.Valve

Simple valve

Information

Simple controlled valve.

Standard characteristic Kv=f (y) is given at standard conditions (dp0, rho0),

either linear : Kv/Kv1 = Kv0/Kv1 + (1-Kv0/Kv1) * y/Y1
or exponential: Kv/Kv1 = Kv0/Kv1 * exp[log(Kv1/Kv0) * y/Y1]

where:

Kv0 ... min. flow @ y = 0
Y1 .... max. valve opening
Kv1 ... max. flow @ y = Y1

Flow resistance under real conditions is calculated by

V_flow**2 * rho / dp = Kv(y)**2 * rho0 / dp0

Extends from Interfaces.Partials.TwoPort (Partial model of two port).

Parameters

Name Description

medium Medium in the component

T0 Initial temperature of medium [K]

T0fixed Initial temperature guess value or fixed

tapT Defines temperature of heatPort between inlet and outlet temperature

frictionLoss Part of friction losses fed to medium

Standard characteristic

LinearCharacteristic Type of characteristic

y1 Max. valve opening

Kv1 Max. flow @ y = y1 [m3/s]

kv0 Leakage flow / max.flow @ y = 0

dp0 Standard pressure drop [Pa]

rho0 Standard medium's density [kg/m3]

Name	Description
medium	Medium in the component
T0	Initial temperature of medium [K]
T0fixed	Initial temperature guess value or fixed
tapT	Defines temperature of heatPort between inlet and outlet temperature
frictionLoss	Part of friction losses fed to medium
Standard characteristic
LinearCharacteristic	Type of characteristic
y1	Max. valve opening
Kv1	Max. flow @ y = y1 [m3/s]
kv0	Leakage flow / max.flow @ y = 0
dp0	Standard pressure drop [Pa]
rho0	Standard medium's density [kg/m3]

Connectors

Name Description

flowPort_a

flowPort_b

y

Name	Description
flowPort_a
flowPort_b
y

Automatically generated Mon Sep 23 17:21:08 2013.