Permeable Zone (2D) Data Fields

Permeable Zone (2D) data can be edited on either the Permeable Zone (2D) Grid Window of the Polygon Grid or the Permeable Zone (2D) Property Sheet.

Most data can be edited on the grid, but some fields cannot be displayed in the grid format.

To view and edit all 2D permeable zone data, use the Property Sheet.

The following section describes all the data which can be used to define a Permeable Zone (2D).

For details of results fields, see the Permeable Zone (2D) Results Data Fields topic.

Common Data Fields

Fields that are common to the majority of objects can be found in the Common Fields topic.

Permeable Zone (2D) Data

Database Table Name: hw_2d_permeable_zone

Show Columns	Database Names
	Size, Type and Units
	Defaults and Error Limits

Field Name

Help Text

Database Field

Data Type

Size

Units

Precision

Default

Error Lower Limit

Error Upper Limit

Warning Lower Limit

Warning Upper Limit

A unique name used to identify this permeable zone (2D).

polygon_id

Text

Area

The area of the permeable zone (2D) polygon is automatically calculated when the polygon is generated on the GeoPlan.

The boundaries of one permeable zone (2D) polygon must not overlap with the boundaries of another permeable zone (2D) polygon.

area

Double

Exclude permeable zone boundary when creating 2D mesh

A check in the box (default) indicates that the 2D permeable zone boundaries are not to be used as break lines when creating a 2D mesh that incorporates this permeable zone. Remove the check from the box if the 2D permeable zone boundaries are to be used as break lines during meshing.

exclude_from_2d_mesh

Drains to

The type of object to which this 2D permeable zone drains. Choose an object type from the drop-down list:

Option	Help Text
Node	The Node ID field is enabled, allowing you to specify to which node the zone drains.
Link	The Node ID and Link Suffix fields are enabled, allowing you to specify to which link the zone drains.
Subcatchment	The To subcatchment ID field is enabled, allowing you to specify to which subcatchment the zone drains.
Multiple links	The Lateral links and Lateral weights fields are enabled, allowing you to specify to which links the zone drains.

drains_to

Text

Node ID

The name of node which this 2D permeable zone drains to. The name can be either be typed in or selected from a drop-down list of all nodes in the current network. The zone can only drain to either a manhole, storage, break or pond type of node.

node_id

Text

Link suffix

The link suffix of a single link that the 2D permeable zone drains to. In order for a zone to drain to a single link, both the Node ID and Link suffix fields must be filled-in.

When running a simulation, the simulation engine applies infiltrated volume from the permeable zone laterally along the link identified by the Node ID and Link suffix fields.

link_suffix

Text

To Subcatchment ID

The name of a subcatchment which this 2D permeable zone drains to. This name can be either be typed in or chosen from the drop-down list.

to_subcatchment_id

Text

Lateral links

This field contains a series of records defining all the lateral links which a 2D permeable zone can drain to.

The records are entered on the Lateral links grid which is displayed by clicking on the button.

Field Name

Help Text

Node ID

The node to which this lateral link drains. The name of the node can either be typed in or selected from a list of all nodes in the current network.

Link suffix

The link suffix to which this lateral link drains.

Weight

If the Lateral weights field is set to User, then this field is enabled and is used to specify the proportion of the total weight that is to be assigned to this lateral link. The total of all links included in the grid must add up to 1.

If the Lateral weights field is set to Length, then this field is read-only and displays the calculated weight values. These values are calculated to be proportional to the length of the associated links and normalised so that the sum of all weights adds up to 1.

If no link exists in the network with an ID corresponding to the Node ID and Link suffix specified in a grid row, then the weight is zero for that row.

If a change is made to the network (after the grid values have been saved by clicking OK), and the grid editor is re-opened, the Length-based weights will be updated, if the change affects the weighting. For example, if an entry in the grid row is saved but it does not have a corresponding link (therefore Weight=0), and a corresponding link is subsequently created in the network and the grid editor is re-opened, then a non-zero weight, determined by the new link’s length, will be displayed.

The Length-based weights are also updated during the validation process. Therefore, it is not necessary to re-open the grid editor in order to update the weights before performing a simulation.

For lateral links, the volume from a 2D permeable zone is connected laterally. However, if any link is a control, then the volume into that link will be connected at the upstream node unless that node is an outfall, in which case it will be connected at the downstream node. If the nodes at both ends of a link are outfalls, then the volume will be lost.

lateral _links

Structure

Lateral weights

The method by which the weighting for the Lateral links is to be set can be chosen from the drop-down list. Set to either User, to indicate that the user is to specify the proportion of the 2D permeable zone drainage that is assigned to each link, or to Length (default), to indicate that weightings are to be calculated by the system.

lateral_weights

Text

Length

Permeable Zones (2D)

Permeable Zone (2D) Results Data Fields

Polygons

Polygon Grid

Property Sheets