Beginner Modeling Tips

Beginner Modeling Tips


When developing a model, it is recommended that the user adopts the following approach:

 

1.Build the model in sections using a step-by-step approach. It is prudent to develop the model in sections, testing each section as you build the model as this will help eliminate any fundamental errors. If each section converges successfully, the final model should also converge without any difficulty. If one of your smaller sub-models will not converge, it is unlikely your final model will converge.

 

2.Keep the flowsheet as simple as possible.

 

3.Keep connector pipes as short as possible. The more compact the model the easier to navigate.

 

4.Use multiple components wherever possible. For instance a pipe containing several elbows may be simplified by setting the “Quantity” of the elbow element to represent more than one elbow. You may use this approach for liquid systems, however, it is recommended that this approach is not used when modelling gas systems due to the changes in gas density which has a knock on effect on calculated pressure loss, thus effecting accuracy.

 

5.When creating a new model, always ensure the base calculation settings are correct and have not been changed by another user for a specific modelling application. It is also prudent to check the Warnings & Hints settings to ensure it matches your design criteria.

 

6.When developing a model which has tees with three different diameter pipe connections, there is no need to add a reducer to each connection as the software will automatically detect this scenario and include in the calculations.  

 

Note, users have the option of adjusting calculation convergence criteria. However, unless you have a valid reason for doing so it is not recommended that these settings be adjusted.

 

If any of the above is unclear or you require any further information, please contact us at: support@fluidflowinfo.com.


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