Gas Objects

This section presents an in-depth description of all objects available in SAInt to develop a gas network model. Figure 1 shows the hierarchy and the parent-child relationships between base objects. Table 1 gives a quick and short description of the base objects.

For example, the top level base object in a gas network model is the "Gas Network" object GNET. A gas network contains many other different base objects, such as, for example, gas nodes GNO or gas branches GBR. GNET is the parent, and GNO or GBR is a child. A gas network object has no parents, but only children. A gas component object GCMP cannot be a parent, but only a child. See the schematic below for a visual representation of the complete hierarchical object structure for a gas network model in SAInt.

Relationship between objects in a gas network. A child object is indicated by the head of a pointed arrow, while a parent is by the tail. Please, open the image in another window of your Internet browser to enlarge it.
Figure 1. Relationship between objects in a gas network. A child object is indicated by the head of a pointed arrow, while a parent is by the tail. Please, open the image in another window of your Internet browser to enlarge it.
Table 1. Icons and descriptions of the objects in gas network.
Icon ObjType Display Name Description

gnet

GNET

Gas Network

Models the characteristics and interactions of facilities and/or components of a gas network. Serves as a container for all objects in the gas network

gsub

GSUB

Gas Sub

Models a subset of nodes, branches, and gas externals of an gas network. A gas sub is branch-oriented, i.e., only gas branches can be assigned to a gas sub, and every gas branch belongs to only one gas sub

gzn

GZN

Gas Zone

Models a subset of nodes, branches, and externals of a gas network. A gas zone is node-oriented, i.e., only gas nodes can be assigned to a gas zone, and every gas node belongs to only one gas zone

ggrp

GGRP

Gas Group

Models a subset of different objects in a gas network. Except for the gas network, subs, and zones, any gas object can be added to a gas group. In contrast to gas subs and zones, gas groups do not follow any specific assignment rules. Thus, a gas object can be part of multiple gas groups

gno

GNO

Gas Node

Models a physical or virtual location in the gas network where gas can be injected or extracted through externals (gas demand, supply, storage, etc.)

gpi

GPI

Gas Pipeline

Models the transport of gas between two distant locations

gcs

GCS

Gas Compressor

Models the increase of inlet pressure to a higher outlet pressure to ensure continuous transport and delivery of gas to customers at the contracted nominations and delivery pressures

gcv

GCV

Gas Control Valve

Models the reduction of inlet pressure to lower outlet pressure or the control of gas flow to a downstream network

gva

GVA

Gas Valve

Models a valve station, which is used to route the gas stream and shut down sections of the network for maintenance or in case of a disruption.

gre

GRE

Gas Resistor

Models passive devices that cause a local pressure drop, such as meters inlet piping, scrubbers, coolers, heaters, etc

gsup

GSUP

Gas Supply

Models the injection of gas at a node

gdem

GDEM

Gas Demand

Models the consumption of gas at a node

gstr

GSTR

Gas Storage

Models the withdrawal and injection of gas from/into the storage inventory of an (underground) gas storage facility

lng

LNG

LNG terminal

Models the arrival of LNG-vessels and the discharge, storage, regasification, and injection of liquefied natural gas in an LNG regasification terminal

gqual

GQUAL

Gas Quality

Models the thermo dynamic properties (gross/net calorific value, relative density, etc.) and the mixtures of different gas molecules (gas components) flowing through the network

gcmp

GCMP

Gas Component

Models the thermo dynamic properties (gross/net calorific value, relative density, etc.) of a gas molecule included in the gas mixture

gcus

GCUS

Gas Component Usage

Models the molar percentage of mixture of a gas component included in a gas quality

1. Gas network (GNET)

A gas network object is the top parent object in any model of a gas system in SAInt (Figure 1). A gas network object is modeled as a directed graph consisting of a set of gas nodes, branches, and externals that are connected with one another. A gas network contains a description of all geometric, topological, and relational information, as well as all network child objects and their static properties that do not change during the execution of a simulation (e.g., the length and the diameter of a gas pipeline).

The "nodes" of a gas network are objects that identify either junctions among the network branches or physical points where gas can be supplied to or withdrawn from the system.

The "branches" of a gas network are objects that establish how nodes and externals are connected and can passively (e.g., with gas pipelines) or actively (e.g., with gas compressor stations or control valves) modify the state of the gas that flows through them. Branches of a gas network are "pipelines", "compressor stations", "control valves", "valves", and "resistors".

The "externals" of a gas network represent objects supplying or withdrawing gas from the system. Externals of a gas network are "supplies", "demands", "storages", and "LNG terminals".

A gas network also contains further gas-specific objects like "gas qualities", and "gas components".

Scenario events define a change in the settings of a gas network object during the execution of a scenario. Gas network events can be used to customize the network and simulation settings and to compare the effect of different assumptions across simulation scenarios. The following list describes the scenario events available for a network object.

  • Intro

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GNET.

Summary for the derived-result properties of GNET.
Extension Description UnitType

FB

Flow balance

QSVOL

INV

Total available storage inventory

LP

LP

Total linepack

LP

BAL

Mass Conservation Equation

LP

POWDMAX

Maximum driver power

POW

QMAX

Maximum branch flow

QSVOL

VMAX

Maximum velocity

VEL

PMAX

Maximum pressure

P

TMAX

Maximum temperature

T

POWDMIN

Minimum driver power

POW

QMIN

Minimum branch flow

QSVOL

VMIN

Minimum velocity

VEL

PMIN

Minimum pressure

P

TMIN

Minimum temperature

T

POWD

Total driver power

POW

QIN

Total inflow

QSVOL

QOUT

Total outflow

QSVOL

POWS

Total shaft power

POW

Summary for the event-default properties of GNET.
Extension Description UnitType

TAMBDEF

Default ambient temperature

T

Summary for the event-value properties of GNET.
Extension Description UnitType

TAMB

Ambient temperature

T

LPREF

Reference line pack for comparing results

LP

Summary for the net-input properties of GNET.
Extension Description UnitType

PAMB

Ambient pressure

PD

Pz_b

Base pressure for custom compressibility factor equation: Z(P.bar) = 1 + Z_1 * P.bar + Z_2 * ((P.bar - Pz_b.bar) ^2 - Pz_b.bar ^2)

PD

ZEQN

Equation for computing compressibility factor

CRSType

Network coordinate reference system for the node locations

LAMEQN

Equation for computing friction factor

Info

Information related to the network model. Any character, including non-alphanumeric, is allowed

Kappa

Isentropic exponent, i.e. ratio between isobaric and isochoric heat capacity

ND

Z_1

Coefficient of linear term in custom compressibility factor equation: Z(P.bar) = 1 + Z_1 * P.bar + Z_2 * ((P.bar - Pz_b.bar) ^2 - Pz_b.bar ^2)

ND

Z_2

Coefficient of quadratic term in custom compressibility factor equation: Z(P.bar) = 1 + Z_1 * P.bar + Z_2 * ((P.bar - Pz_b.bar) ^2 - Pz_b.bar ^2)

ND

Pn

Pressure at reference condition

PD

Tn

Reference temperature

T

VarPAMB

Consider ambient pressure dependence on the elevation

VISC

Dynamic viscosity used for calculating the friction factor

VISC

Summary for the net-read-only properties of GNET.
Extension Description UnitType

DMAX

Maximum branch inner diameter

D

DMIN

Minimum branch inner diameter

D

Name

Name of the network model. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters.

NetType

Network Type

NUMBR

Number of branches in the network, sub, zone or group

NO

NUMXT

Number of externals in the network, sub, zone or group

NO

NUMLOOP

Number of closed loops in the network, sub, zone or group

NO

NUMNO

Number of nodes in the network, sub, zone or group

NO

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GNET.
Parameter Type Description UnitType

H

IniSetting

Constant elevation. Minimum: 0.

H

HTON

IniSetting

Turn on temperature tracking.

NO

LAM

IniSetting

Constant friction factor. Minimum: 0.

ND

LPREF

Reference

Reference linepack. Minimum: 0.

LP

QTOFF

IniSetting

Turn off gas quality tracking.

NO

RO

IniSetting

Constant roughness. Minimum: 0.

RO

TAMB

Ambient

Ambient temperature. Minimum: 0.

T

Z

IniSetting

Constant compressibility factor. Minimum: 0.

ND

2. Gas network container

The child objects of a network can be grouped into the following subsets, also referred to as "containers": sub, zone, and group. These arrangements can be used to define relevant information for a network, or they can simply be used to conveniently aggregate outputs of a scenario.

2.1. Gas sub (GSUB)

A sub (also referred to as sub-network or sub-system) is a subset of nodes, branches, and externals of a network. A sub is branch-oriented, i.e., only branches can be assigned to a sub, and every branch belongs to only one sub. The FromNode and ToNode of a branch, as well as the externals connected to these two nodes, are implicitly added to the sub. Thus, nodes connecting branches of different subs and the externals connected to these nodes are always included in multiple subs. But all properties of a sub are determined by the branches belonging to it.

  • Intro

  • derived-result

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GSUB.

Summary for the derived-result properties of GSUB.
Extension Description UnitType

FB

Flow balance

QSVOL

INV

Total available storage inventory

LP

LP

Total linepack

LP

BAL

Mass Conservation Equation

LP

POWDMAX

Maximum driver power

POW

QMAX

Maximum branch flow

QSVOL

VMAX

Maximum velocity

VEL

PMAX

Maximum pressure

P

TMAX

Maximum temperature

T

POWDMIN

Minimum driver power

POW

QMIN

Minimum branch flow

QSVOL

VMIN

Minimum velocity

VEL

PMIN

Minimum pressure

P

TMIN

Minimum temperature

T

POWD

Total driver power

POW

QIN

Total inflow

QSVOL

QOUT

Total outflow

QSVOL

POWS

Total shaft power

POW

Summary for the event-value properties of GSUB.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the net-input properties of GSUB.
Extension Description UnitType

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

Summary for the net-read-only properties of GSUB.
Extension Description UnitType

DMAX

Maximum branch inner diameter

D

DMIN

Minimum branch inner diameter

D

NetType

Network Type

NUMBR

Number of branches in the network, sub, zone or group

NO

NUMXT

Number of externals in the network, sub, zone or group

NO

NUMLOOP

Number of closed loops in the network, sub, zone or group

NO

NUMNO

Number of nodes in the network, sub, zone or group

NO

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GSUB.
Parameter Type Description UnitType

TAMB

Ambient

Ambient temperature. Minimum: 0.

T

2.2. Gas zone (GZN)

A zone is a subset of nodes, branches, and externals of a gas network. Differently from subs, zones are node-oriented, i.e., only nodes can be assigned to a zone, and every node belongs to one zone. Branches with a FromNode and ToNode belonging to the same zone are implicitly added to the corresponding zone. In contrast, branches with a FromNode and ToNode belonging to two different zones do not belong to any zone. Externals are also implicitly added to the zone of the node they are connected to. But all properties of a zone are determined by the nodes belonging to it.

  • Intro

  • derived-result

  • net-input

  • net-read-only

Summaries for the properties and the events of GZN.

Summary for the derived-result properties of GZN.
Extension Description UnitType

FB

Flow balance

QSVOL

INV

Total available storage inventory

LP

LP

Total linepack

LP

BAL

Mass Conservation Equation

LP

POWDMAX

Maximum driver power

POW

QMAX

Maximum branch flow

QSVOL

VMAX

Maximum velocity

VEL

PMAX

Maximum pressure

P

TMAX

Maximum temperature

T

POWDMIN

Minimum driver power

POW

QMIN

Minimum branch flow

QSVOL

VMIN

Minimum velocity

VEL

PMIN

Minimum pressure

P

TMIN

Minimum temperature

T

POWD

Total driver power

POW

QIN

Total inflow

QSVOL

QOUT

Total outflow

QSVOL

POWS

Total shaft power

POW

Summary for the net-input properties of GZN.
Extension Description UnitType

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

Summary for the net-read-only properties of GZN.
Extension Description UnitType

DMAX

Maximum branch inner diameter

D

DMIN

Minimum branch inner diameter

D

NetType

Network Type

NUMBR

Number of branches in the network, sub, zone or group

NO

NUMXT

Number of externals in the network, sub, zone or group

NO

NUMLOOP

Number of closed loops in the network, sub, zone or group

NO

NUMNO

Number of nodes in the network, sub, zone or group

NO

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

2.3. Gas group (GGRP)

A group is a subset of different child object types (e.g., nodes, branches, externals, etc.) of the whole network. In contrast to subs and zones, groups do not follow any specific assignment rules. Thus, a child object can be assigned to multiple groups, and a group can have as many child objects assigned to it as there are child objects in the network.

  • Intro

  • derived-result

  • net-input

  • net-read-only

Summaries for the properties and the events of GGRP.

Summary for the derived-result properties of GGRP.
Extension Description UnitType

FB

Flow balance

QSVOL

INV

Total available storage inventory

LP

LP

Total linepack

LP

BAL

Mass Conservation Equation

LP

POWDMAX

Maximum driver power

POW

QMAX

Maximum branch flow

QSVOL

VMAX

Maximum velocity

VEL

PMAX

Maximum pressure

P

TMAX

Maximum temperature

T

POWDMIN

Minimum driver power

POW

QMIN

Minimum branch flow

QSVOL

VMIN

Minimum velocity

VEL

PMIN

Minimum pressure

P

TMIN

Minimum temperature

T

POWD

Total driver power

POW

QIN

Total inflow

QSVOL

QOUT

Total outflow

QSVOL

POWS

Total shaft power

POW

Summary for the net-input properties of GGRP.
Extension Description UnitType

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

Summary for the net-read-only properties of GGRP.
Extension Description UnitType

DMAX

Maximum branch inner diameter

D

DMIN

Minimum branch inner diameter

D

NetType

Network Type

NUMCNSTR

Number of branches in the network, sub, zone or group

NO

NUMBR

Number of branches in the network, sub, zone or group

NO

NUMXT

Number of externals in the network, sub, zone or group

NO

NUMLOOP

Number of closed loops in the network, sub, zone or group

NO

NUMNO

Number of nodes in the network, sub, zone or group

NO

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

3. Gas node (GNO)

Nodes represent objects describing a junction among two or more gas branches, as well as a location in the gas network where gas can be injected or extracted through externals (e.g., demand, supply, etc.).

  • Intro

  • base-result

  • derived-event-value

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GNO.

Summary for the base-result properties of GNO.
Extension Description UnitType

P

Pressure at nodes

P

T

Temperature at nodes

T

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Summary for the derived-event-value properties of GNO.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the derived-result properties of GNO.
Extension Description UnitType

RHO

Gas density

RHO

QNS

Difference between flow rate set point and actual flow rate

Q

Z

Compressibility at nodes

ND

Q

In- or Outflow at nodes

Q

c

Speed of sound at nodes

VEL

QVOL

Volumetric in- or outflow at nodes

QVOL

TQ

Thermal flow

TQ

PNS

Difference between scheduled thermal flow and actual thermal flow

TQ

Summary for the event-default properties of GNO.
Extension Description UnitType

PMAXDEF

Default maximum pressure

P

PMAXPRCDEF

Default penalty price for maximum pressure. If PMAXPRCDEF > 0, P will be limited to PMAX. if PMAXPRCDEF = -inf, simulation will cease upon exceeding PMAX. if PMAXPRCDEF = 0, exceeding PMAX will result in a warning

PPRC

PMINDEF

Default minimum pressure

P

PMINPRCDEF

Default penalty price for minimum pressure. If PMINPRCDEF > 0, P will be limited to PMIN. If PMINPRCDEF = -inf, simulation will cease when P falls below PMIN. If PMINPRCDEF = 0, going below PMIN will result in a warning

PPRC

Summary for the event-value properties of GNO.
Extension Description UnitType

PMAX

Maximum pressure constraint

P

PMAXPRC

Penalty price for maximum pressure. If PMAXPRC > 0, P will be limited to PMAX. if PMAXPRC = -inf, simulation will cease upon exceeding PMAX. if PMAXPRC = 0, exceeding PMAX will result in a warning

PPRC

PMIN

Minimum pressure constraint

P

PMINPRC

Penalty price for minimum pressure. If PMINPRC > 0, P will be limited to PMIN. If PMINPRC = -inf, simulation will cease when P falls below PMIN. If PMINPRC = 0, going below PMIN will result in a warning

PPRC

QREF

Reference flow rate for comparing results

Q

PREF

Reference nodal pressure for comparing results

P

TREF

Reference nodal temperature for comparing results

T

Summary for the net-input properties of GNO.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

H

Elevation

H

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

Visible

If true, the object symbol will be visible in maps

NO

X

Cartesian X coordinate for visualizing the node in the map. Externals assigned to the node are not displayed

XY

Y

Cartesian Y coordinate for visualizing the node in the map. Externals assigned to the node are not displayed

XY

ZoneName

ZoneName of the zone the node belongs to

Summary for the net-read-only properties of GNO.
Extension Description UnitType

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GNO.
Parameter Type Description UnitType

OFF

ControlSetPoint

Turn off connected externals.

NO

PMAX

Constraint

Maximum nodal pressure. Minimum: 0.

P

PMAXPRC

PenaltyPrice

Penalty price for maximum nodal pressure.

PPRC

PMIN

Constraint

Minimum nodal pressure. Minimum: 0.

P

PMINPRC

PenaltyPrice

Penalty price for minimum nodal pressure.

PPRC

PREF

Reference

Reference nodal pressure. Minimum: 0.

P

QREF

Reference

Reference flow rate.

Q

TREF

Reference

Reference nodal temperature. Minimum: 0.

T

4. Gas branch (GBR)

A branch is a general type of object which describes a generic connection between two gas nodes. Different types of branches exist in SAInt and the following sections provides more details on each of them.

4.1. Gas pipeline (GPI)

A gas pipeline is an object which models the transport of gas between two locations and connects two nodes. Gas pipelines (also referred to as pipes) are passive branches, as no active control can be imposed over them. Gas flowing along a gas pipeline is subject to pressure drops due to friction. The magnitude of the pressure drop depends on the flow rate, the composition, the thermodynamic state of the gas (pressure, temperature), and on the properties of the pipelines (diameter, length, internal roughness).

  • Intro

  • base-result

  • derived-result

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GPI.

Summary for the base-result properties of GPI.
Extension Description UnitType

T

Average temperature in the pipeline

T

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Q

Mass flow rate in the pipeline

Q

Summary for the derived-result properties of GPI.
Extension Description UnitType

Z

Average compressibility in the pipeline

ND

P

Average pressure in the pipeline

P

c

Average speed of sound in the pipeline

VEL

V

Flow velocity

VEL

LAM

Friction factor

ND

RHOI

Inlet density

RHO

VI

Flow velocity at the inlet of the branch

VEL

PI

Inlet node pressure

P

TI

Inlet temperature

T

QVOLI

Volumetric flow rate at the inlet of the branch

QVOL

LP

Total line pack in pipeline

LP

RHOO

Outlet density

RHO

VO

Flow velocity at the outlet of the branch

VEL

PO

Pressure of outlet node

P

TO

Outlet temperature

T

QVOLO

Volumetric flow rate at the outlet of the branch

QVOL

QVOL

Volumetric flow in the pipeline

QVOL

PD

Pressure difference between outlet and inlet in flow direction

PD

PR

Pressure ratio between outlet and inlet node

ND

RF

Resistance factor

ND

REY

Reynolds number

ND

TRVL

Average travel time of a particle in pipeline

TIME

Summary for the event-value properties of GPI.
Extension Description UnitType

TAMB

Ambient temperature

T

QREF

Reference flow rate for comparing results

Q

Summary for the net-input properties of GPI.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DrawLine

If true, element will be drawn as a straight line and internal points will be neglected

NO

FromName

Name of FromNode

HTC

Heat transfer coefficient

HTC

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

D

Inner pipe diameter or design diameter of non-pipe branches

D

RO

Inner wall roughness of pipeline

RO

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

Eff

Pipeline efficiency

ND

L

Pipeline length

L

SubName

Sub the branch belongs to

ToName

Name of ToNode

Visible

If true, the object symbol will be visible in maps

NO

WTH

Thickness of the pipe wall

D

Summary for the net-read-only properties of GPI.
Extension Description UnitType

A

Cross sectional area

AREA

DH

Elevation difference between inlet and outlet nodes

H

LGEO

Length According to Map Coordinates

L

ALPHA

Pipeline inclination

ANGLE

LD

Difference between actual pipeline length and geographic length

L

NetType

Network Type

J

Number of pipe segments after pipe discretization

ND

ID

Object Identification

ObjType

Object Type

DOUT

Outer pipe diameter, based on the wall thickness and inner diameter

D

VOL

Geometric pipe volume

VOL

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GPI.
Parameter Type Description UnitType

QREF

Reference

Reference flow rate.

Q

TAMB

Ambient

Ambient temperature. Minimum: 0.

T

Inlet and outlet-derived properties do not depend on the flow direction but on the drawing direction of the pipeline (i.e., from which start node to which end node).

4.2. Gas compressor (GCS)

A gas compressor is an object that increases the inlet gas pressure to a higher outlet pressure to ensure continuous transport and delivery of natural gas to its customers at the contracted nominations and delivery pressures. A gas compressor is an active branch connecting two nodes, and it requires an assigned control mode (scenario event) to operate. Gas compressors typically use part of the fuel that they process to produce compression work. In the current release of SAInt, the fuel consumed at a compressor station is not accounted for any flow balance the compressor station contributes to, but it is set apart.

  • Intro

  • base-result

  • derived-event-value

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GCS.

Summary for the base-result properties of GCS.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLSETVAL

Scheduled station control value

NO

CTRLVAL

Control set point value

NO

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Q

Mass flow rate in the pipeline

Q

Summary for the derived-event-value properties of GCS.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the derived-result properties of GCS.
Extension Description UnitType

HAD

Adiabatic head

HAD

Z

Inlet compressibility factor

ND

P

Average pressure in the pipeline

P

c

Average speed of sound in the pipeline

VEL

POWD

Driver power

POW

V

Flow velocity

VEL

FUEL

Required fuel for compression

Q

RHOI

Inlet density

RHO

VI

Flow velocity at the inlet of the branch

VEL

PI

Inlet node pressure

P

TI

Inlet temperature

T

QVOLI

Volumetric flow rate at the inlet of the branch

QVOL

RHOO

Outlet density

RHO

VO

Flow velocity at the outlet of the branch

VEL

PO

Pressure of outlet node

P

TO

Outlet temperature

T

QVOLO

Volumetric flow rate at the outlet of the branch

QVOL

QVOL

Volumetric flow in the pipeline

QVOL

PD

Pressure difference between outlet and inlet in flow direction

PD

PR

Pressure ratio between outlet and inlet node

ND

POWS

Shaft power

POW

Summary for the event-default properties of GCS.
Extension Description UnitType

EFFHDEF

Default average adiabatic efficiency

ND

POWDMAXDEF

Default maximum driver power

POW

POWDMAXPRCDEF

Default Penalty price for maximum driver power. If POWDMAXPRC > 0, POWD will be limited to POWDMAX. If POWDMAXPRCDEF = -inf, simulation will cease upon exceeding POWDMAX. If POWDMAXPRCDEF = 0, exceeding POWDMAX will result in a warning

NRGPRC

QMAXDEF

Default maximum flow rate

QSVOL

QMAXPRCDEF

Default penalty price for maximum flow rate. If QMAXPRCDEF > 0, Q will be limited to QMAX. If QMAXPRCDEF = -inf, simulation will cease upon exceeding QMAX. If QMAXPRCDEF = 0, exceeding QMAX will result in a warning

LPPRC

POMAXDEF

Default maximum outlet pressure

P

POMAXPRCDEF

Default penalty price for maximum outlet pressure. If POMAXPRCDEF > 0, PO will be limited to POMAX. If POMAXPRCDEF = -inf, simulation will cease upon exceeding POMAX. If POMAXPRCDEF = 0, exceeding POMAX will result in a warning

PPRC

PRMAXDEF

Default maximum pressure ratio

ND

PRMAXPRCDEF

Default penalty price for maximum pressure ratio. If PRMAXPRCDEF > 0, PR will be limited to PRMAX. If PRMAXPRCDEF = -inf, simulation will cease upon exceeding PRMAX. If PRMAXPRCDEF = 0, exceeding PRMAX will result in a warning

C

POWSMAXDEF

Default maximum shaft power

POW

POWSMAXPRCDEF

Default penalty price for maximum shaft power. If POWSMAXPRC > 0, POWS will be limited to POWSMAX. If POWSMAXPRCDEF = -inf, simulation will cease upon exceeding POWSMAX. If POWSMAXPRCDEF = 0, exceeding POWSMAX will result in a warning

NRGPRC

VMAXDEF

Default maximum flow velocity

VEL

VMAXPRCDEF

Default penalty price for maximum flow velocity. If VMAXPRCDEF > 0, V will be limited to VMAX. If VMAXPRCDEF = -inf, simulation will cease upon exceeding VMAX. If VMAXPRCDEF = 0, exceeding VMAX will result in a warning

LPRC

QVOLMAXDEF

Default maximum volumetric flow rate

QVOL

QVOLMAXPRCDEF

Default penalty price for maximum volumetric flow rate. If QVOLMAXPRC > 0, QVOL will be limited to QVOLMAX. If QVOLMAXPRCDEF = -inf, simulation will cease upon exceeding QVOLMAX. If QVOLMAXPRCDEF = 0, exceeding QVOLMAX will result in a warning

VOLPRC

EFFMDEF

Default average driver efficiency

ND

PIMINDEF

Default minimum inlet pressure

P

PIMINPRCDEF

Default penalty price for minimum inlet pressure. If PIMINPRCDEF > 0, PI will be limited to PIMIN. If PIMINPRCDEF = -inf, simulation will cease when PI falls below PIMIN. If PIMINPRCDEF = 0, going below PIMIN will result in a warning

PPRC

Summary for the event-value properties of GCS.
Extension Description UnitType

EFFH

Average adiabatic efficiency

ND

POWDMAX

Maximum available driver power

POW

POWDMAXPRC

Penalty price for maximum driver power. If POWDMAXPRC > 0, POWD will be limited to POWDMAX. If POWDMAXPRC= -inf, simulation will cease upon exceeding POWDMAX. If POWDMAXPRC = 0, exceeding POWDMAX will result in a warning

NRGPRC

QMAXPRC

Penalty price for maximum flow rate. If QMAXPRC > 0, Q will be limited to QMAX. If QMAXPRC = -inf, simulation will cease upon exceeding QMAX. If QMAXPRC = 0, exceeding QMAX will result in a warning

LPPRC

QMAX

Maximum flow rate

Q

VMAX

Maximum flow velocity

VEL

POMAX

Maximum outlet pressure constraint

P

POMAXPRC

Penalty price for maximum outlet pressure. If POMAXPRC > 0, PO will be limited to POMAX. If POMAXPRC = -inf, simulation will cease upon exceeding POMAX. If POMAXPRC = 0, exceeding POMAX will result in a warning

PPRC

PRMAX

Maximum pressure ratio

ND

PRMAXPRC

Penalty price for maximum pressure ratio. If PRMAXPRC > 0, PR will be limited to PRMAX. If PRMAXPRC = -inf, simulation will cease upon exceeding PRMAX. If PRMAXPRC = 0, exceeding PRMAX will result in a warning

C

POWSMAX

Maximum shaft power

POW

POWSMAXPRC

Penalty price for maximum shaft power. If POWSMAXPRC > 0, POWS will be limited to POWSMAX. If POWSMAXPRC = -inf, simulation will cease upon exceeding POWSMAX. If POWSMAXPRC = 0, exceeding POWSMAX will result in a warning

NRGPRC

VMAXPRC

Penalty price for maximum flow velocity. If VMAXPRC > 0, V will be limited to VMAX. If VMAXPRC = -inf, simulation will cease upon exceeding VMAX. If VMAXPRC = 0, exceeding VMAX will result in a warning

LPRC

QVOLMAX

Maximum volumetric flow rate

QVOL

QVOLMAXPRC

Penalty price for maximum volumetric flow rate. If QVOLMAXPRC > 0, QVOL will be limited to QVOLMAX. If QVOLMAXPRC = -inf, simulation will cease upon exceeding QVOLMAX. If QVOLMAXPRC=0, exceeding QVOLMAX will result in a warning

VOLPRC

EFFM

Average driver efficiency

ND

PIMIN

Minimum inlet pressure constraint

P

PIMINPRC

Penalty price for minimum inlet pressure. If PIMINPRC > 0, PI will be limited to PIMIN. If PIMINPRC = -inf, simulation will cease when PI falls below PIMIN. If PIMINPRC = 0, going below PIMIN will result in a warning

PPRC

QREF

Reference flow rate for comparing results

Q

Summary for the net-input properties of GCS.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DrawLine

If true, element will be drawn as a straight line and internal points will be neglected

NO

ExtractFuel

Extract required fuel from inlet node

NO

FromName

Name of FromNode

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

D

Inner pipe diameter or design diameter of non-pipe branches

D

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

RemoteName

Name of gas remote node

SubName

Sub the branch belongs to

ToName

Name of ToNode

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GCS.
Extension Description UnitType

A

Cross sectional area

AREA

DH

Elevation difference between inlet and outlet nodes

H

LGEO

Length According to Map Coordinates

L

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GCS.
Parameter Type Description UnitType

BP

ControlSetPoint

Turn station into bypass.

NO

EFFH

Efficiency

Average adiabatic efficiency. Minimum: 0. Maximum: 1.

ND

EFFM

Efficiency

Average driver efficiency. Minimum: 0. Maximum: 1.

ND

FUELSET

ControlSetPoint

Fuel consumption set point. Minimum: 0.

Q

NRBP

ControlSetPoint

Turn station into non-return bypass.

NO

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PDSET

ControlSetPoint

Pressure difference set point. Minimum: 0.

PD

PIMIN

Constraint

Minimum inlet pressure. Minimum: 0.

P

PIMINPRC

PenaltyPrice

Penalty price for minimum inlet pressure.

PPRC

PISET

ControlSetPoint

Inlet pressure set point. Minimum: 0.

P

POMAX

Constraint

Maximum outlet pressure. Minimum: 0.

P

POMAXPRC

PenaltyPrice

Penalty price for maximum outlet pressure.

PPRC

POSET

ControlSetPoint

Outlet pressure set point. Minimum: 0.

P

POWDMAX

Constraint

Maximum driver power. Minimum: 0.

POW

POWDMAXPRC

PenaltyPrice

Penalty price for maximum driver power.

NRGPRC

POWDSET

ControlSetPoint

Driver power set point. Minimum: 0.

POW

POWSMAX

Constraint

Maximum shaft power. Minimum: 0.

POW

POWSMAXPRC

PenaltyPrice

Penalty price for maximum shaft power.

NRGPRC

POWSSET

ControlSetPoint

Shaft power set point. Minimum: 0.

POW

PREMSET

ControlSetPoint

Remote pressure set point. Minimum: 0.

P

PRMAX

Constraint

Maximum pressure ratio. Minimum: 1. Maximum: 5.

ND

PRMAXPRC

PenaltyPrice

Penalty price for maximum pressure ratio.

C

PRSET

ControlSetPoint

Pressure ratio set point. Minimum: 1. Maximum: 5.

ND

QMAX

Constraint

Maximum flow rate. Minimum: 0.

Q

QMAXPRC

PenaltyPrice

Penalty price for maximum flow rate.

LPPRC

QREF

Reference

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point. Minimum: 0.

Q

QVOLMAX

Constraint

Maximum volumetric flow rate. Minimum: 0.

QVOL

QVOLMAXPRC

PenaltyPrice

Penalty price for maximum volumetric flow rate.

VOLPRC

QVOLSET

ControlSetPoint

Volumetric flow rate set point. Minimum: 0.

QVOL

R

ControlSetPoint

Resistance factor. Minimum: 0.

ND

VMAX

Constraint

Maximum flow velocity. Minimum: 0.

VEL

VMAXPRC

PenaltyPrice

Penalty price for maximum flow velocity.

LPRC

4.3. Gas resistor (GRE)

A gas resistor is an object describing any passive device that reduces the pressure of the gas flowing across it. A gas resistor can be used to model pressure drops across different objects such as gas meters, coolers, heaters, etc.

  • Intro

  • base-result

  • derived-event-value

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GRE.

Summary for the base-result properties of GRE.
Extension Description UnitType

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Q

Mass flow rate in the pipeline

Q

Summary for the derived-event-value properties of GRE.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the derived-result properties of GRE.
Extension Description UnitType

Z

Inlet compressibility factor

ND

P

Average pressure in the pipeline

P

c

Average speed of sound in the pipeline

VEL

V

Flow velocity

VEL

RHOI

Inlet density

RHO

VI

Flow velocity at the inlet of the branch

VEL

PI

Inlet node pressure

P

TI

Inlet temperature

T

QVOLI

Volumetric flow rate at the inlet of the branch

QVOL

RHOO

Outlet density

RHO

VO

Flow velocity at the outlet of the branch

VEL

PO

Pressure of outlet node

P

TO

Outlet temperature

T

QVOLO

Volumetric flow rate at the outlet of the branch

QVOL

QVOL

Volumetric flow in the pipeline

QVOL

PD

Pressure difference between outlet and inlet in flow direction

PD

PR

Pressure ratio between outlet and inlet node

ND

Summary for the event-default properties of GRE.
Extension Description UnitType

RDEF

Resistance factor

ND

Summary for the event-value properties of GRE.
Extension Description UnitType

QREF

Reference flow rate for comparing results

Q

R

Resistance factor

ND

Summary for the net-input properties of GRE.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DrawLine

If true, element will be drawn as a straight line and internal points will be neglected

NO

FromName

Name of FromNode

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

D

Inner pipe diameter or design diameter of non-pipe branches

D

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

SubName

Sub the branch belongs to

ToName

Name of ToNode

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GRE.
Extension Description UnitType

A

Cross sectional area

AREA

DH

Elevation difference between inlet and outlet nodes

H

LGEO

Length According to Map Coordinates

L

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GRE.
Parameter Type Description UnitType

QREF

Reference

Reference flow rate.

Q

R

SetPoint

Resistance factor. Minimum: 0.

ND

4.4. Gas control valve (GCV)

A gas control valve is an object that reduces the inlet gas pressure to a lower outlet pressure and regulates the quantity of gas flowing through the station. A gas control valve is an active branch, and it requires an assigned control mode (scenario event) to operate.

  • Intro

  • base-result

  • derived-event-value

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GCV.

Summary for the base-result properties of GCV.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLSETVAL

Scheduled station control value

NO

CTRLVAL

Control set point value

NO

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Q

Mass flow rate in the pipeline

Q

Summary for the derived-event-value properties of GCV.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the derived-result properties of GCV.
Extension Description UnitType

Z

Inlet compressibility factor

ND

P

Average pressure in the pipeline

P

c

Average speed of sound in the pipeline

VEL

V

Flow velocity

VEL

RHOI

Inlet density

RHO

VI

Flow velocity at the inlet of the branch

VEL

PI

Inlet node pressure

P

TI

Inlet temperature

T

QVOLI

Volumetric flow rate at the inlet of the branch

QVOL

RHOO

Outlet density

RHO

VO

Flow velocity at the outlet of the branch

VEL

PO

Pressure of outlet node

P

TO

Outlet temperature

T

QVOLO

Volumetric flow rate at the outlet of the branch

QVOL

QVOL

Volumetric flow in the pipeline

QVOL

PD

Pressure difference between outlet and inlet in flow direction

PD

PR

Pressure ratio between outlet and inlet node

ND

Summary for the event-default properties of GCV.
Extension Description UnitType

QMAXDEF

Default maximum flow rate

QSVOL

QMAXPRCDEF

Default penalty price for maximum flow rate. If QMAXPRCDEF > 0, Q will be limited to QMAX. If QMAXPRCDEF = -inf, simulation will cease upon exceeding QMAX. If QMAXPRCDEF = 0, exceeding QMAX will result in a warning

LPPRC

POMAXDEF

Default maximum outlet pressure

P

POMAXPRCDEF

Default penalty price for maximum outlet pressure. If POMAXPRCDEF > 0, PO will be limited to POMAX. If POMAXPRCDEF = -inf, simulation will cease upon exceeding POMAX. If POMAXPRCDEF = 0, exceeding POMAX will result in a warning

PPRC

VMAXDEF

Default maximum flow velocity

VEL

VMAXPRCDEF

Default penalty price for maximum flow velocity. If VMAXPRCDEF > 0, V will be limited to VMAX. If VMAXPRCDEF = -inf, simulation will cease upon exceeding VMAX. If VMAXPRCDEF = 0, exceeding VMAX will result in a warning

LPRC

QVOLMAXDEF

Default maximum volumetric flow rate

QVOL

QVOLMAXPRCDEF

Default penalty price for maximum volumetric flow rate. If QVOLMAXPRC > 0, QVOL will be limited to QVOLMAX. If QVOLMAXPRCDEF = -inf, simulation will cease upon exceeding QVOLMAX. If QVOLMAXPRCDEF = 0, exceeding QVOLMAX will result in a warning

VOLPRC

PIMINDEF

Default minimum inlet pressure

P

PIMINPRCDEF

Default penalty price for minimum inlet pressure. If PIMINPRCDEF > 0, PI will be limited to PIMIN. If PIMINPRCDEF = -inf, simulation will cease when PI falls below PIMIN. If PIMINPRCDEF = 0, going below PIMIN will result in a warning

PPRC

Summary for the event-value properties of GCV.
Extension Description UnitType

QMAXPRC

Penalty price for maximum flow rate. If QMAXPRC > 0, Q will be limited to QMAX. If QMAXPRC = -inf, simulation will cease upon exceeding QMAX. If QMAXPRC = 0, exceeding QMAX will result in a warning

LPPRC

QMAX

Maximum flow rate

Q

VMAX

Maximum flow velocity

VEL

POMAX

Maximum outlet pressure constraint

P

POMAXPRC

Penalty price for maximum outlet pressure. If POMAXPRC > 0, PO will be limited to POMAX. If POMAXPRC = -inf, simulation will cease upon exceeding POMAX. If POMAXPRC = 0, exceeding POMAX will result in a warning

PPRC

VMAXPRC

Penalty price for maximum flow velocity. If VMAXPRC > 0, V will be limited to VMAX. If VMAXPRC = -inf, simulation will cease upon exceeding VMAX. If VMAXPRC = 0, exceeding VMAX will result in a warning

LPRC

QVOLMAX

Maximum volumetric flow rate

QVOL

QVOLMAXPRC

Penalty price for maximum volumetric flow rate. If QVOLMAXPRC > 0, QVOL will be limited to QVOLMAX. If QVOLMAXPRC = -inf, simulation will cease upon exceeding QVOLMAX. If QVOLMAXPRC=0, exceeding QVOLMAX will result in a warning

VOLPRC

PIMIN

Minimum inlet pressure constraint

P

PIMINPRC

Penalty price for minimum inlet pressure. If PIMINPRC > 0, PI will be limited to PIMIN. If PIMINPRC = -inf, simulation will cease when PI falls below PIMIN. If PIMINPRC = 0, going below PIMIN will result in a warning

PPRC

QREF

Reference flow rate for comparing results

Q

Summary for the net-input properties of GCV.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DrawLine

If true, element will be drawn as a straight line and internal points will be neglected

NO

FromName

Name of FromNode

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

D

Inner pipe diameter or design diameter of non-pipe branches

D

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

RemoteName

Name of gas remote node

SubName

Sub the branch belongs to

ToName

Name of ToNode

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GCV.
Extension Description UnitType

A

Cross sectional area

AREA

DH

Elevation difference between inlet and outlet nodes

H

LGEO

Length According to Map Coordinates

L

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GCV.
Parameter Type Description UnitType

BP

ControlSetPoint

Turn station into bypass.

NO

NRBP

ControlSetPoint

Turn station into non-return bypass.

NO

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PDSET

ControlSetPoint

Pressure difference set point. Minimum: 0.

PD

PIMIN

Constraint

Minimum inlet pressure. Minimum: 0.

P

PIMINPRC

PenaltyPrice

Penalty price for minimum inlet pressure.

PPRC

PISET

ControlSetPoint

Inlet pressure set point. Minimum: 0.

P

POMAX

Constraint

Maximum outlet pressure. Minimum: 0.

P

POMAXPRC

PenaltyPrice

Penalty price for maximum outlet pressure.

PPRC

POSET

ControlSetPoint

Outlet pressure set point. Minimum: 0.

P

PREMSET

ControlSetPoint

Remote pressure set point. Minimum: 0.

P

QMAX

Constraint

Maximum flow rate. Minimum: 0.

Q

QMAXPRC

PenaltyPrice

Penalty price for maximum flow rate.

LPPRC

QREF

Reference

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point. Minimum: 0.

Q

QVOLMAX

Constraint

Maximum volumetric flow rate. Minimum: 0.

QVOL

QVOLMAXPRC

PenaltyPrice

Penalty price for maximum volumetric flow rate.

VOLPRC

QVOLSET

ControlSetPoint

Volumetric flow rate set point. Minimum: 0.

QVOL

R

ControlSetPoint

Resistance factor. Minimum: 0.

ND

VMAX

Constraint

Maximum flow velocity. Minimum: 0.

VEL

VMAXPRC

PenaltyPrice

Penalty price for maximum flow velocity.

LPRC

4.5. Gas valve (GVA)

A gas valve is an object that stops or limits the gas flow between two connected nodes. It is an active branch, and it requires an assigned control mode (scenario event) to operate. A gas valve can be modeled as open (bypass) or closed (off). In reality, gas valves can also be partially closed to control flow velocity. In such cases, these objects may exert a non-negligible resistance to the flow.

  • Intro

  • base-result

  • derived-event-value

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GVA.

Summary for the base-result properties of GVA.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLSETVAL

Scheduled station control value

NO

CTRLVAL

Control set point value

NO

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Q

Mass flow rate in the pipeline

Q

Summary for the derived-event-value properties of GVA.
Extension Description UnitType

TAMB

Ambient temperature

T

Summary for the derived-result properties of GVA.
Extension Description UnitType

Z

Inlet compressibility factor

ND

P

Average pressure in the pipeline

P

c

Average speed of sound in the pipeline

VEL

V

Flow velocity

VEL

RHOI

Inlet density

RHO

VI

Flow velocity at the inlet of the branch

VEL

PI

Inlet node pressure

P

TI

Inlet temperature

T

QVOLI

Volumetric flow rate at the inlet of the branch

QVOL

RHOO

Outlet density

RHO

VO

Flow velocity at the outlet of the branch

VEL

PO

Pressure of outlet node

P

TO

Outlet temperature

T

QVOLO

Volumetric flow rate at the outlet of the branch

QVOL

QVOL

Volumetric flow in the pipeline

QVOL

PD

Pressure difference between outlet and inlet in flow direction

PD

PR

Pressure ratio between outlet and inlet node

ND

Summary for the event-default properties of GVA.
Extension Description UnitType

VMAXDEF

Default maximum flow velocity

VEL

VMAXPRCDEF

Default penalty price for maximum flow velocity. If VMAXPRCDEF > 0, V will be limited to VMAX. If VMAXPRCDEF = -inf, simulation will cease upon exceeding VMAX. If VMAXPRCDEF = 0, exceeding VMAX will result in a warning

LPRC

Summary for the event-value properties of GVA.
Extension Description UnitType

VMAX

Maximum flow velocity

VEL

VMAXPRC

Penalty price for maximum flow velocity. If VMAXPRC > 0, V will be limited to VMAX. If VMAXPRC = -inf, simulation will cease upon exceeding VMAX. If VMAXPRC = 0, exceeding VMAX will result in a warning

LPRC

QREF

Reference flow rate for comparing results

Q

Summary for the net-input properties of GVA.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DrawLine

If true, element will be drawn as a straight line and internal points will be neglected

NO

FromName

Name of FromNode

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

D

Inner pipe diameter or design diameter of non-pipe branches

D

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

SubName

Sub the branch belongs to

ToName

Name of ToNode

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GVA.
Extension Description UnitType

A

Cross sectional area

AREA

DH

Elevation difference between inlet and outlet nodes

H

LGEO

Length According to Map Coordinates

L

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GVA.
Parameter Type Description UnitType

BP

ControlSetPoint

Turn station into bypass.

NO

NRBP

ControlSetPoint

Turn station into non-return bypass.

NO

OFF

ControlSetPoint

Turn off facility, service or object.

NO

QREF

Reference

Reference flow rate.

Q

R

ControlSetPoint

Resistance factor. Minimum: 0.

ND

VMAX

Constraint

Maximum flow velocity. Minimum: 0.

VEL

VMAXPRC

PenaltyPrice

Penalty price for maximum flow velocity.

LPRC

5. Gas external (GXT)

A directed connection to a single gas node which allows the extraction and injection of gas at that node. A gas external is used to model demands, supplies, storage facilities and LNG terminals in a gas network. An arbitrary number of gas externals can be assigned to a gas node.

5.1. Gas demand (GDEM)

A gas demand object represents a demand for gas at a particular node. A gas demand withdraws gas from the network, and it can be assigned with a flow rate or pressure control set-point.

  • Intro

  • base-result

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GDEM.

Summary for the base-result properties of GDEM.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLVAL

Control set point value

NO

CTRLSETVAL

Control set point value

NO

Q

Fluid offtake/supply

Q

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Summary for the derived-result properties of GDEM.
Extension Description UnitType

QNS

Difference between flow rate set point and actual flow rate

Q

P

Pressure at nodes

P

TQ

Thermal flow

TQ

PNS

Difference between scheduled thermal flow and actual thermal flow

TQ

Summary for the event-default properties of GDEM.
Extension Description UnitType

QMAXPRCDEF

Default penalty price for maximum inflow/outflow. If QMAXPRCDEF > 0, Q will be limited to QMAX. If QMAXPRCDEF = -inf, simulation will cease upon exceeding QMAX. if QMAXPRCDEF = 0, exceeding QMAX will result in a warning

LPPRC

QMAXDEF

Default maximum inflow/outflow

QSVOL

Summary for the event-value properties of GDEM.
Extension Description UnitType

QSET

Flow rate set point

Q

QMAXPRC

Penalty price for maximum inflow/outflow. If QMAXPRC > 0, Q will be limited to QMAX. If QMAXPRC = -inf, simulation will cease upon exceeding QMAX. if QMAXPRC = 0, exceeding QMAX will result in a warning

LPPRC

QMAX

Maximum inflow/outflow constraint

Q

PSET

Pressure set point

P

QREF

Reference flow rate for comparing results

Q

Summary for the net-input properties of GDEM.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NodeName

Name of node the external is connected to

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GDEM.
Extension Description UnitType

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GDEM.
Parameter Type Description UnitType

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PSET

ControlSetPoint

Pressure control set point. Minimum: 0.

P

QMAX

Constraint

Maximum flow rate. Minimum: 0.

Q

QMAXPRC

PenaltyPrice

Penalty price for maximum flow rate.

LPPRC

QREF

None

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point.

Q

5.2. Gas supply (GSUP)

A gas supply object represents a facility supplying gas in correspondence of a particular node. A gas supply injects gas into the network, and it can be assigned with a flow rate or pressure control set-point. A gas supply can be coupled with a gas quality object to specify its gas composition. A gas supply injects gas with a default quality (DefaultQuality property of the gas network) when no quality is specified, or when a turn off quality tracking (QTOFF) event for the gas network is introduced in the simulation scenario.

  • Intro

  • base-result

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GSUP.

Summary for the base-result properties of GSUP.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLVAL

Control set point value

NO

CTRLSETVAL

Control set point value

NO

Q

Fluid offtake/supply

Q

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

Summary for the derived-result properties of GSUP.
Extension Description UnitType

QNS

Difference between flow rate set point and actual flow rate

Q

P

Pressure at nodes

P

TQ

Thermal flow

TQ

PNS

Difference between scheduled thermal flow and actual thermal flow

TQ

Summary for the event-default properties of GSUP.
Extension Description UnitType

QMAXPRCDEF

Default penalty price for maximum inflow/outflow. If QMAXPRCDEF > 0, Q will be limited to QMAX. If QMAXPRCDEF = -inf, simulation will cease upon exceeding QMAX. if QMAXPRCDEF = 0, exceeding QMAX will result in a warning

LPPRC

QMAXDEF

Default maximum inflow/outflow

QSVOL

Summary for the event-value properties of GSUP.
Extension Description UnitType

QSET

Flow rate set point

Q

QMAXPRC

Penalty price for maximum inflow/outflow. If QMAXPRC > 0, Q will be limited to QMAX. If QMAXPRC = -inf, simulation will cease upon exceeding QMAX. if QMAXPRC = 0, exceeding QMAX will result in a warning

LPPRC

QMAX

Maximum inflow/outflow constraint

Q

PSET

Pressure set point

P

QREF

Reference flow rate for comparing results

Q

TSET

Supply temperature set point

T

Summary for the net-input properties of GSUP.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NodeName

Name of node the external is connected to

SQSETNAME

Name of scheduled supply gas quality

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GSUP.
Extension Description UnitType

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GSUP.
Parameter Type Description UnitType

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PSET

ControlSetPoint

Pressure control set point. Minimum: 0.

P

QMAX

Constraint

Maximum flow rate. Minimum: 0.

Q

QMAXPRC

PenaltyPrice

Penalty price for maximum flow rate.

LPPRC

QPSET

ControlSetPoint

Nodal inflow participation set point. Minimum: 0. Maximum: 100.

PC

QREF

Reference

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point.

Q

TSET

SetPoint

Supply temperature set point. Minimum: 0.

T

5.3. Gas storage (GSTR)

A gas storage object represents an underground storage facility located in correspondence with a particular node. A gas storage can supply or absorb gas from the network depending on its control mode and the network conditions. Typically, the rate at which gas can be injected into or withdrawn from the gas storage depends on its inventory. The consequent operating region of a gas storage is reflected by its storage envelope.

  • Intro

  • base-result

  • derived-result

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of GSTR.

Summary for the base-result properties of GSTR.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLVAL

Control set point value

NO

CTRLSETVAL

Control set point value

NO

Q

Fluid offtake/supply

Q

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

INV

Gas inventory

LP

Summary for the derived-result properties of GSTR.
Extension Description UnitType

QNS

Difference between flow rate set point and actual flow rate

Q

P

Pressure at nodes

P

TQ

Thermal flow

TQ

PNS

Difference between scheduled thermal flow and actual thermal flow

TQ

Summary for the event-value properties of GSTR.
Extension Description UnitType

QSET

Flow rate set point

Q

PSET

Pressure set point

P

QREF

Reference flow rate for comparing results

Q

TSET

Supply temperature set point

T

Summary for the net-input properties of GSTR.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

INJMIN

Maximum storage injection rate at maximum working inventory

QSVOL

INJMAX

Maximum storage injection rate at minimum working inventory

QSVOL

INVMAX

Maximum working gas inventory

LP

WDRMAX

Maximum storage withdrawal rate at maximum working inventory

QSVOL

WDRMIN

Maximum storage withdrawal rate at minimum working inventory

QSVOL

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NodeName

Name of node the external is connected to

INVINJ

Relative inventory at injection slope point (INVINJ ⇐ 1)

ND

INVWDR

Relative inventory at withdrawal slope point (INVWDR ⇐ 1)

ND

UGSTYPE

Storage facility type

NO

SQSETNAME

Name of scheduled supply gas quality

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of GSTR.
Extension Description UnitType

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of GSTR.
Parameter Type Description UnitType

INV

IniState

Initial storage inventory. Minimum: 0.

LP

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PSET

ControlSetPoint

Pressure control set point. Minimum: 0.

P

QPSET

ControlSetPoint

Nodal inflow participation set point. Minimum: 0. Maximum: 100.

PC

QREF

Reference

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point.

Q

TSET

SetPoint

Supply temperature set point. Minimum: 0.

T

5.4. LNG terminal (LNG)

An LNG terminal object represents a liquefied natural gas (LNG) regasification terminal in correspondence with a particular node. An LNG terminal supplies gas to the network, and it can be assigned a flow rate or pressure control set-point. Volumes of gas supplied to the grid are withdrawn from the LNG terminal storage tanks as long as its inventory value is greater than zero. The LNG storage tank can be recharged during a simulation scenario by modeling the arrival of LNG vessels.

  • Intro

  • base-result

  • derived-result

  • event-default

  • event-value

  • net-input

  • net-read-only

  • event

Summaries for the properties and the events of LNG.

Summary for the base-result properties of LNG.
Extension Description UnitType

CTRL

Control mode of controlled facility

NO

CTRLSET

Scheduled station control

NO

CTRLVAL

Control set point value

NO

CTRLSETVAL

Control set point value

NO

INVVES

Amount of gas discharged from vessel to LNG storage tank

VOL

Q

Fluid offtake/supply

Q

VOLVES

Volume of LNG to unload from arriving vessel(s)

VOL

State

Current operating state of object. Permitted states are ON and OFF. When referred to a node, all externals connected to the node inherit the state

INV

Gas inventory

LP

Summary for the derived-result properties of LNG.
Extension Description UnitType

QNS

Difference between flow rate set point and actual flow rate

Q

INVLNG

LNG working inventory

VOL

P

Pressure at nodes

P

TQ

Thermal flow

TQ

PNS

Difference between scheduled thermal flow and actual thermal flow

TQ

Summary for the event-default properties of LNG.
Extension Description UnitType

QMAXPRCDEF

Default penalty price for maximum inflow/outflow. If QMAXPRCDEF > 0, Q will be limited to QMAX. If QMAXPRCDEF = -inf, simulation will cease upon exceeding QMAX. if QMAXPRCDEF = 0, exceeding QMAX will result in a warning

LPPRC

QMAXDEF

Default maximum inflow/outflow

QSVOL

Summary for the event-value properties of LNG.
Extension Description UnitType

QSET

Flow rate set point

Q

QMAXPRC

Penalty price for maximum inflow/outflow. If QMAXPRC > 0, Q will be limited to QMAX. If QMAXPRC = -inf, simulation will cease upon exceeding QMAX. if QMAXPRC = 0, exceeding QMAX will result in a warning

LPPRC

QMAX

Maximum inflow/outflow constraint

Q

PSET

Pressure set point

P

QREF

Reference flow rate for comparing results

Q

TSET

Supply temperature set point

T

Summary for the net-input properties of LNG.
Extension Description UnitType

Alias

Alternative object name. Any character, including non-alphanumeric, is allowed

DIS

Vessel Discharge Rate. Volumetric flow rate for relocating LNG from Vessel to LNG Storage tanks

QVOL

Info

Information entered for the object. Any character, including non-alphanumeric, is allowed

InService

Indicates if an object is considered or disregarded in the execution of a scenario. Externals connected to the node inherit the "inService" status of the node

dLNG

LNG relative density ⇒ density of LNG at reference conditions (p_n, T_n) divided by density of natural gas at reference conditions (p_n,T_n)

ND

INVMAX

Maximum working gas inventory

LP

VESMAX

Maximum vessel size

VOL

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NodeName

Name of node the external is connected to

SQSETNAME

Name of scheduled supply gas quality

Visible

If true, the object symbol will be visible in maps

NO

Summary for the net-read-only properties of LNG.
Extension Description UnitType

INVLNGMAX

Maximum LNG working inventory in storage tank

VOL

NetType

Network Type

ID

Object Identification

ObjType

Object Type

UID

Unique identifier for the object which cannot be changed during the lifetime of the object

Summary for the events of LNG.
Parameter Type Description UnitType

INV

IniState

Initial storage inventory. Minimum: 0.

LP

OFF

ControlSetPoint

Turn off facility, service or object.

NO

PSET

ControlSetPoint

Pressure control set point. Minimum: 0.

P

QMAX

Constraint

Maximum flow rate. Minimum: 0.

Q

QMAXPRC

PenaltyPrice

Penalty price for maximum flow rate.

LPPRC

QPSET

ControlSetPoint

Nodal inflow participation set point. Minimum: 0. Maximum: 100.

PC

QREF

Reference

Reference flow rate.

Q

QSET

ControlSetPoint

Flow rate set point.

Q

TSET

SetPoint

Supply temperature set point. Minimum: 0.

T

VESSEL

SetPoint

Arriving vessel size. Minimum: 0.

VOL

6. Gas quality (GQUAL)

A gas quality object represents a mixture of gas components. Every gas network has a default gas quality defined. Besides that, other supply qualities can be added from the GUI or by importing them from a file. These can be assigned to gas supplies, storages, and LNG terminals from their input properties.

Input properties of a gas quality object include the molar composition and the thermo-physical characteristics of the gas mixture, like its gross/net calorific values and molar mass. The molar concentrations of the components should sum up to 100%. By default, thermo-physical properties are automatically computed based on the composition. However, custom values can also be used to overwrite calculated properties.

  • Intro

  • net-input

  • net-read-only

Summaries for the properties and the events of GQUAL.

Summary for the net-input properties of GQUAL.
Extension Description UnitType

PC

Critical pressure

PD

TC

Critical temperature

T

GCV

Gross calorific value

CV

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NCV

Net calorific value

CV

RHOr

Relative density

ND

Summary for the net-read-only properties of GQUAL.
Extension Description UnitType

RHOn

Gas density at reference conditions

RHO

R

Specific gas constant of gas mixture

MCP

M

Molar mass of the fluid component

MOL

WOB

Wobbe number

CV

6.1. Gas component (GCMP)

SAInt is not limited to model transportation and distribution of natural gas. It can effortlessly model a wide variety of gas mixtures (i.e., a gas quality) by creating and managing gas components. SAInt offers a built-in library of common gas components to create and adapt a gas quality to the user’s specific needs. It also provides a straightforward and simple capability for defining a new component when not available. Gas components can be mixed to obtain a certain gas quality, whose properties are estimated by SAInt or derived by the user inputs.

A gas component represents a pure chemical species to be used for the creation of gas quality objects. Every gas network has a list of gas component objects that can be used to define gas qualities. The list of gas components contains, by default, only methane and can be expanded by picking more gas components from the built-in library available in SAInt. New custom gas component objects can also be defined.

The library covers the main hydrocarbons and the most common impurities and can be easily extended. The full list of components, and associated SAInt code in brackets, is:

Hydrocarbons

methane (C1), ethane (C2), propane (C3), iso-butane (IC4), n-butane (NC4), iso-pentane (IC5), n-pentane (NC5), n-hexane (NC6), n-heptane (NC7), n-octane (NC8), n-nonane (NC9), n-decane (NC10);

Non Hydrocarbons

where we can distinguish inert gases like nitrogen (N2), rare gasses like argon (AR) and helium (HE), impurities like hydrogen sulfide (H2S), water (H2O), oxygen (O2), carbon monoxide (CO), or carbon dioxide (CO2), and other gasses like hydrogen (H2).

In brackets is reported the string used for the property ShortName in SAInt for the component and not its chemical notation.

A gas component has a set of physical and energy related properties. As an example, Figure 2 shows the properties for methane. Please, note that the properties of the components in the built-in library cannot be edited. The user can only modify the properties of user-defined components.

create gas component 00
Figure 2. Example of the properties of the gas component methane (C1).

Gas components, as gas qualities, are objects within a network object.

The physical and energy properties (e.g., gross/net calorific value, relative density, molar mass, etc.) of a gas component included in SAInt built-in library cannot be edited. In the case of a custom gas component, specific properties can be described in input.

  • Intro

  • net-input

  • net-read-only

Summaries for the properties and the events of GCMP.

Summary for the net-input properties of GCMP.
Extension Description UnitType

PC

Critical pressure

PD

TC

Critical temperature

T

GCV

Gross calorific value

CV

Name

Object Name. Permitted characters are letters, numbers, and underscore ("_"). The name should start with a letter, and have a length of 1 to 30 characters. The name should be unique for each object type

NCV

Net calorific value

CV

RHOr

Relative density

ND

ShortName

Short name of fluid component used as an extension to access mixture fraction

NO

Summary for the net-read-only properties of GCMP.
Extension Description UnitType

RHOn

Gas density at reference conditions

RHO

R

Specific gas constant of gas mixture

MCP

M

Molar mass of the fluid component

MOL

WOB

Wobbe number

CV