Best practices for models

Consider the following guidelines as you set up a model for analysis:

• Use a systematic approach to identify the location and calibration setup for each instrument in the model.

• Associate every instrument with the correct flow, and make sure that temperature and specific gravity corrections are applied to flow measurements if needed. Check whether this function of correction is performed by your control system or historian.

• Validate tank/inventory properties by building a tank-only model, including shipments and receipts. Enter the materials list with its properties at the same time.

• Determine the calibration tolerance of each instrument (you can use ISO 5167 for orifice meters), or refer to meter data sheets and manufacturers.

• Build and examine individual unit models before attempting to connect them and run a multi-unit analysis.

• After you achieve full unit connectivity, examine the entire drawing, and then run a balance analysis to identify flows and connections that cannot be solved.