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.

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.
ObjType	Display Name	Description
`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`	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`	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`	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`	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`	Gas Pipeline	Models the transport of gas between two distant locations
`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`	Gas Control Valve	Models the reduction of inlet pressure to lower outlet pressure or the control of gas flow to a downstream network
`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`	Gas Resistor	Models passive devices that cause a local pressure drop, such as meters inlet piping, scrubbers, coolers, heaters, etc
`GSUP`	Gas Supply	Models the injection of gas at a node
`GDEM`	Gas Demand	Models the consumption of gas at a node
`GSTR`	Gas Storage	Models the withdrawal and injection of gas from/into the storage inventory of an (underground) gas storage facility
`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`	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`	Gas Component	Models the thermo dynamic properties (gross/net calorific value, relative density, etc.) of a gas molecule included in the gas mixture
`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.

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.

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.).

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).

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

Refer to the following How-Tos for more details on Add a Gas Component, Create and Edit a Gas Quality in the GUI, or How to Import/Export Gas Qualities.