Abstract: The purpose of this paper is to study the sensible factors of“gel dam” in-depth fluid diversion technique
by numerical simulation. By using the ECLIPSE commercial simulator， targeted at two-layer 2D model， five-layer
2D model and one five-layer five-spot pattern model， we study the sensible factors for“gel dam” in-depth fluid
diversion technique， such as the location， height and number of the“gel dam” . The results indicate that the“gel
dam” in-depth fluid diversion technique is an effective EOR method. When the“gel dam” or the horizontal well is
in the middle of the well spacing or near to the production well， there will have a higher effectiveness. The higher
the“gel dams” are， more effective the water flooding is. If many gel dams with height up to more than 40% of
reservoir thickness are joint together， there will be a better EOR effectiveness. The sooner the“gel dam” measure
has be taken， the more volumetric sweep efficiency can be increased. Even if the“gel dams” measure has been
taken at very high water cut， the recovery of the reservoir can also increase. If the“gel dam” measure is adopted
and combined with water shutoff， the oil recovery of the thick positive rhythm reservoir can be enhanced in a long
time. The conclusions provide a valuable guidance for field trial.

Key words: numericalsimulation, horizontalwell, geldam, in-depthfluiddiversion, thickpositiverhythmreservoir