Check Files 1d mhc
This GIS layer contains information on the Manholes in the 1D model. Manholes are used to model energy losses at junctions and can occur in the same location as pit channels (which convey water between the ground and the underground drainage network. The manholes can be manually assigned or automatically created and numerous loss methods are available. Refer to the TUFLOW manual for further guidance.
Attributes of mhc_check
| Attribute Name | Attribute Description |
|---|---|
| ID | The ID of the manhole. |
| Type | The type of manhole, options are:
|
| Loss_Approach | The manhole loss approach. The options are outlined in the Manhole section of the TUFLOW Manual. |
| Ignore | If the manhole has been set to ignore. |
| Invert_Level | The bottom or bed elevation of the manhole. |
| Flow_Width | The flow width of the manhole chamber. Losses are calculated as the flow expands into the manhole chamber and contracts into the outgoing channel. |
| Flow_Length | The length of the manhole chamber in the direction of flow. |
| ANA | Any additional nodal area that has been added at the manhole (value in square metres or square feet). |
| K_Fixed | Fixed component of the calculated manhole loss coefficient. If using the Fixed approach, this is the only coefficient applied. |
| Km | Manhole exit coefficient used by the Engelhund approach. |
| K_Bend_Max | The upper limit of the combination of KƟ and Kdrop in the Engelhund approach. |
| C_reserved | Not used. |
| N1_reserved | Not used. |
| N2_reserved | Not used. |
| N3_reserved | Not used. |
| i_1d_layer | The index to the input layer that has created the manhole. For example an i_1d_layer value of 4 would be the 4th input layer (1d_nwk_M08_pits_001) below. Read GIS Network == mi\1d_nwk_M04_channels_001.MIF |
| No_Inlet_Culverts | The number of incoming culverts based on the digitised direction. |
| No_Outlet_Culverts | The number of outgoing culverts based on the digitised direction. |
| Highest_Soffit | The elevation of the highest soffit (obvert) for the connected channels. |
| Surface_Area | The surface area of the manhole. |
For MapInfo users the style of the point object is dependent on the manhole type and dimensions. For example a "C" (circular) type manhole is shown as a circle object with the size proportional to the flow width.