There are two new settings that allow the user to place tighter constraints upon convergence.

Headloss Error Limit

The Headloss Error Limit is found under the Hydraulics category in the main calculation options.

The description for the field is as follows: Specifies the maximum head loss error that any network link can have for hydraulic convergence to occur. A link's head loss error is the difference between the head loss found as a function of computed flow in the link (such as by the Hazen-Williams equation for a pipe) and the difference in computed heads for the link's end nodes. The default value of 0 indicates that no head error limit applies.

Specifying a lower Headloss Error Limit will reduce the chance of successful convergence but may improve the accuracy of the calculation in certain circumstances.

Flow Change Limit

The Flow Change Limit is found under the Hydraulics category in the main calculation options.

The description for the field is as follows: Specifies the largest change in flow that any network element can possess for hydraulic convergence to occur. The default value of 0.0 indicates that no flow limit applies.

Specifying a lower Flow Change Limit will reduce the chance of successful convergence but may improve the accuracy of the calculation in certain circumstances.