Hydraulics of an irrigation system

[bdgloomis]

I am trying to model the hydraulics of an irrigation system, not using any rainfall events in the model, but use a defined lateral flow. I entered a base value for a lateral inflow on the upstream junction and then route this flow through my pipe network. I am getting greater flows through each pipe then my inflow amount. I figure this max flow in each link is computed based on the slope and the link characteristics. If this is the case, I then removed the inflow value on the network and ran the simulation. This simulation produced a zero max flow for the upstream link and values for all of the downstream links.

What is stormnet doing in this model? Does any body have any thoughts?

[Chris Maeder]

Note that you need to make certain that you have a small enough time step to properly route the water. It the time step is too large, then the model will not capture the routing of flow through the network properly--especially if you have a small network.

Select Analysis | Analysis Options, and make certain that the Routing Time Step is small enough to capture the flow through the shortest pipe (or link) in the system. For example, perhaps based upon the maximum velocity and shortest pipe that the flow routes through this pipe in 5 seconds. Then, you would need to have a routing time step less than 5 seconds.

If you still have problems with your model, please let me know.

[bdgloomis]

I tried to adjust the time step. The program would not let me adjust the time step, but I changed the end reporting time to a small time period. This did not work.

I just want to model a defined flow.

[Chris Maeder]

If you attach your StormNET model as a ZIP file, I will be able to review it to determine what is causing the problem. Alternatively, you can email it to support@bossintl.com and we will review it and let you know what we are able to determine.