Layers of Guidance during Modelling & Simulation

Flownex SE boasts several layers of guidance during the modelling of networks:

·         In drawing up a network Flownex provides guidance to help users set up only solvable and diagrammatically correct networks.

We will briefly discuss the various layers of guidance and how they are applied during simulations next.

Flownex SE User Guidance

User Guidance for Incorrect Network Setup

Flownex SE has an integrated user guidance system, which checks and ensures only diagrammatically correct and valid solvable network models are set up. An example is the specification of links; it is not possible to have flow from opposite directions into a single element. If the drawing rules are not followed the link will be highlighted red and Flownex will not allow the link to be created.

User Guidance for Incorrect/Unrealistic Property Specification

To prevent users from specifying unrealistic input values some properties have limiting ranges or parameters. An example is the specification of a valve opening; it is not possible to open a valve more than 100% therefore if the valve opening is specified above 100% Flownex will not allow the input.

In addition Flownex only shows the relevant properties needed to solve the problem as it is currently configured. Unnecessary and additional properties are hidden from users to avoid confusion.

An example is diameter specification of a pipe, the user has the option to specify if the pipe has a constant or variable diameter, if constant diameter is chosen Flownex will remove the outlet diameter as is no longer required, the process is applied to all Flownex inputs.

Flownex SE Error Handling

The Flownex error handling system guides users when errors are detected during startup or solution of a simulation. The error handling systems detects the error and guides users with a descriptive message detailing the problem. Users can double click on the error to link directly to the to the problem area and correct it. Flownex SE Error Handling functionality decreases troubleshooting time.

Errors

Any error encountered in the solver during the solution process will immediately terminate the solver and the error message will be displayed.

Warnings

Warnings are guidelines for users to evaluate if the limits that were exceeded are acceptable or to investigate the solution some more to ensure that accurate and applicable answers are obtained.

Error Handling for Incorrect/Unrealistic Property Specification

Flownex has a comprehensive set of checks built in that are run before the solver starts to ensure that realistic model inputs are specified. During solve time, the network is constantly monitored and any errors that occur are reported with helpful diagnostic information.

The behaviour of some components or materials is based on experimental data or correlations. The experimental data is mostly added as tables in the chart and lookup table libraries.

When the limit applicability for correlations is reached, the table input value range exceeded or physical limits reached. Flownex SE will indicate this in the form of applicable warnings and errors.

Error Handling for Incorrect Network Setup

When basic network requirements are not achieved during the modelling of a Network, Flownex will guide the user to specify the minimum requirements to ensure the network can solve. The requirements will be indicated in the form of warnings and errors.

The warnings and errors range from fluid specification to component geometry, ensuring all basic requirements to setup a network are met.

Debugging Tools

In addition to the Flownex SE error handling functionality various debugging tools are available to the user to ensure simulation errors are found and corrected efficiently

Group & Component Deactivation

Components can individually and in groups be deactivated from the solver to aid in troubleshooting.

Page Deactivation

Pages can be deactivated from the solver to aid in troubleshooting.

 

Descriptive Errors and Warnings 

Descriptive errors and warnings ensure correct procedures are followed to fix problems.

Users can double click on the errors in the error window to link directly to the to the problem area.

 

 

Find Dialog

The Find Dialog allows users quickly find components in large networks to inspect their properties.

 

Multi-editor Dialog

Multi-editor Dialog allows users to compare inputs of multiple components; this allows for increased speed in troubleshooting property specification errors.

 

Result Layers

Result Layers allow users to graphically display properties with colour on the canvas; this allows rapid troubleshooting of parameter specification. An example is if a pipe network is setup and it is known that all the pipe diameters are similar. A result layer of the diameters can be setup and for all the pipe components. All diameters will be displayed over a defined colour range, if there is a variation in the colour represented by the pipes the user will know the diameter for the specific pipe is specified incorrectly.

 

Enable and Disable the Various Solvers

With the ability to enable and disable the various solvers available in Flownex SE users can effectively troubleshoot solvers.  For instance all Excel of Script components can be disabled by disabling the Excel solver of Scripting solver.