Calculate Flow Arrows add-in
We recently developed a Calculate Flow Arrows community sample that allows a user to visualize the flow direction of subnetworks and have included a copy of the community sample as an add-in on this post. This sample includes quite a few limitations, and we recommend that customers who are serious about understanding the flow in their network seek out partner solutions that do not have these limitations and provide a more robust user experience.
While this add-in is useful for many different kinds of networks, it is designed primarily to support the radial flow found in electric distribution networks. This is different from pressurized pipes of pipeline networks like gas and water, which are either heavily looped (distribution) or possess simple topographies (transmission). This also differs from gravity-based networks such as sewer and stormwater which often use a flow direction field to model the effects of gravity, and visualize the resulting flow in the network, using the techniques described in the Tracing using Digitized Direction article.
Usage
1. Download the add-in from this post and double-click the file to and select Install Add-in to install it.
This add-in was built for ArcGIS Pro 3.5. If you have an older ArcGIS Pro client, this add-in may not load or work properly.
2. Open ArcGIS Pro. On the ribbon you will notice an additional Add-in tab. Select the Add-in tab and you will see a Show Flow Arrows Pane command.
3. Click the Show Flow Arrows command to open the Calculate Flow Arrows pane.
The pane will populate the Tier parameter dropdown with the tiers from the first utility network in your map. You can refresh the list by closing and re-opening the pane.
4. For the Tier parameter, select the tier you want to analyze from the dropdown; this will populate the Subnetworks parameter dropdown with clean subnetworks in the tier.
The pane will only load the first 3000 clean, active subnetworks from the tier. You can force the pane to load dirty subnetworks by clicking the Include Dirty parameter.
5. For the Subnetworks parameter, select the subnetwork you want to analyze and click the Analyze Subnetwork command.
6. The tool will output several log messages as it exports and analyzes the subnetwork.
When the analysis completes it creates a FlowLines feature class added inside the default geodatabase for your project if one doesn’t already exist. You can control whether previous flow arrow results will be deleted from the layer by selecting the Clear previous results parameter.
The first time you run the tool you will need to add the newly created layer to your map.
7. Add the FlowLines layer to your map to visualize the results.
A sample layer file has been included in this article that includes sample symbology. Add it to your map and point it to the FlowLines layer in your project.
8. If the tool was run with the Apply filter parameter checked, a definition query will be applied to the FlowLines layer, and the map will zoom to the selected subnetworks.
9. You can change the active subnetwork, or remove the filter, by changing the active definition query using the Ribbon or layer properties.
This definition query will filter the flow arrows to only show the selected subnetwork.
10. The flow calculated can be one of four different values:
• With Digitized Direction – The flow calculated from the subnetwork controller matches the digitized direction of the line.
• Against Digitized Direction – The flow calculated from the subnetwork controller is in the opposite of the digitized direction of the line.
• Indeterminate – The line was found to be part of a loop within the network.
• Bi-directional – The line is not part of a loop, but the flow calculated for the line is different depending on the subnetwork controller used to calculate flow.
11. The FlowLines layer also includes a chart that can be used to quickly identify features that have indeterminate or bi-directional flow.
Known Limitations
The add-in is provided with several known limitations. Because the utility network doesn’t expose flow information, the tool estimates flow direction for the utility network features. Because of this, there are certain scenarios where the flow direction calculated by this tool may differ from the actual flow direction returned by an upstream/downstream trace of the utility network.
This tool is designed for and works best with balanced electrical distribution networks with a single condition barrier. While it can still be run on circuits that have multiple condition barriers or propagators, the flow will be calculated using more basic logic.
The tool can also be run on subnetworks from other domains but may run slower on large networks or networks with many subnetwork controllers.
If you find that the flow arrows calculated by the tool are incorrect for your network configuration, you should seek out partner solutions for this problem. While it is possible to download and extend the community sample, it requires a deep understanding of the domain being analyzed and graph traversal algorithms.
Conclusion
While this add-in does have many limitations, we felt that it was a good way for customers who were getting familiar with the utility network to begin understanding flow. We also recognize that as customers become familiar with the utility network and more advanced workflows, they will want to rely on partner solutions that don't suffer from the limitations of this tool and provide a more robust user experience.
Please be aware that support is not provided for this tool. If you run into any issues with the add-in or have questions, you can raise these on the community site.
If you want to see any enhancements to the tool or need it Enhancements and support for other releases of ArcGIS Pro can be completed using a version of the Calculate Flow Arrows community sample which you maintain from the ArcGIS Pro SDK Community Samples page.
This add-in is provided with compatibility for ArcGIS Pro 3.5 and supports all utility network schema versions. You can analyze clean subnetworks beginning with ArcGIS Enterprise 10.9. 1; however, analyzing dirty subnetworks requires ArcGIS Enterprise 11.1 or later. This tool supports both capabilities on utility networks contained in File and Mobile geodatabases.
