Mass and Volume

Mass and Volume tabs

These properties appear in the Common Results frame on the Results tab.

These tabs show the same set of data in units of mass and volume. The values presented on these tabs for the selected event include measured flow, compensated mass flow, corrected flow, and reconciled flow. If the compensation checkbox in the Design Operation tab is checked, the compensated flow rate is used in data reconciliation.

Compensation in this context means volume correction to standard conditions based on actual density, temperature and pressure. The volume correction equation that is used to correct volume readings for changes in density (for liquid) or MW (for gas) is a function of variations in temperature and pressure. AVEVA Production Accounting operates based on the assumption that metered rates and amounts fed into AVEVA Production Accounting as measured values are already corrected based on factors programmed into the field instrumentation that assume standard operating conditions (design parameters). When the actual, measured operating conditions vary from the design parameters, it is necessary to reverse the field correction to obtain raw units, then apply the compensation again using the actual, measured density, temperature and pressure (to the extent that these are available). The details for the calculation are in section Flow Compensation.

Corrected mass or volume is used when the Corrected checkbox is checked. Corrected values are manually overridden values. The tolerance in such cases is also manually entered. If this checkbox is checked, the corrected flow rate is used in data reconciliation instead of the measured flow rate or the compensated flow rate, and the compensation checkbox is ignored.