Annular fluid expansion analysis (AFEA) is a vital step when designing an oil/gas well or geothermal well. Traditionally, an AFEA is performed between a drilling operation (initial condition) and a production operation (final condition). However, well design engineers desire to perform an AFEA between any two operations. The objective of this work is to address that challenge.
Sequential AFEA refers to the procedure in which output data (e.g., fluid volume change) of one AFEA are used as input data for another AFEA; the underlying operations are “sequential”. As a result, an AFEA can be configured between any two operations, provided that the “initial condition” operation is before the “final condition” operation.
This two-pass AFEA model has been implemented in computer programs and has been integrated with a commercial software tool, including a wellbore thermal flow simulator and tubular stress analyzer. Offshore well examples were used to validate the model. Case study results indicate that a sequential AFEA is in good agreement with a traditional one-pass AFEA in terms of both forward and backward operation sequences.