Oil and gas well modeling problems and uncertainties such as transient effects in the earth/formation for a single well, repeated shutdown and restart.

  • Transient effects in the earth/formation for a single well
  • Heat transfer between different wells
  • Repeated shutdown and restart
  • Effect of cooling from the ocean. (Vertical heat conduction in the earth/formation around the well bore).
  • Heat transfer in vertical and deviated annuli, where there a mixture of conduction, natural convection and radiation contributes to the heat transfer.
  • Gas lift with cold gas in the annulus. (cross current heat exchanging)
  • Downhole temperatures varies with depth
  • Downhole temperatures varies with location especially where there is a large difference in sea depth between individual wells
  • Geothermal gradient and reservoir. This gradient may vary considerably over the field, especially if the sea depth also varies considerably over the field.
  • Static bottom hole temperature. The reservoir temperature at the same depth may vary over the field due to difference in geothermal gradient and/or sea depth.
  • Flowing bottom hole temperature (FBHT). If there is a large inflow pressure drop, FBHT may be much higher or lower than the reservoir temperature.