화학공학소재연구정보센터
Journal of Canadian Petroleum Technology, Vol.45, No.5, 43-48, 2006
An experimental approach of influences of perforated length and fractures on horizontal well productivity
Many simulation studies have been conducted regarding the importance of Perforated well length on horizontal well performance. All of these studies suffered from their dependence upon! theoretical models, which lack plausibility due to the lack of accurate experimental and/or field data. Therefore, there is a real need for experimental data to be used for tuning the single well simulation models before applying a full field simulation of oil; reservoirs with horizontal wells. This experimental study was designed to investigate the influences of fractions of perforated length, total length, and fractures, which do not intersect with a well axis, on the productivity of horizontal wells. An experimental model (60 cm X 40 cm X 20 cm) was designed and used to achieve the study objectives Carefully sized sandpacks were used to represent. the homogeneous unconsolidated porous media while a perforated aluminum sheet was used as a horizontal fracture parallel (horizontal fracture) and perpendicular but not intersecting (vertical fracture) the horizontal, well axis in the sandpack. Several runs were carried out using horizontal wells with different lengths and different perforation fractions of total length utilizing homogenous porous media with and without fracture systems. The results indicated that an increase of perforated well length increases flow rate of the horizontal well for both homogeneous and fractured formations that do not intersect with the well axis. Furthermore, horizontally-fractured formations parallel to and! vertically-fractured formations vertical to the well axis improve the productivity of horizontal wells for different perforation ratios. A single vertically-fractured porous medium provides a higher productivity ratio than a horizontally-fractured one for the same perforation length and intensity, when both fracture systems 1 do not intersect with the well axis. Several empirical equations. were developed to correlate the horizontal well productivity with perforated length for homogenous and fractured porous media. Ignoring of the effect of pressure drop along horizontal well may have serious implications on perforated well length since proportionality of the productivity index to the well length is no longer valid.