NUMERICAL TREATMENT OF WELLS IN 2D HYBRID GRIDS

Giovani Cerbato¹; Fernando Sandro Velasco Hurtado¹; Gustavo Gondran Ribeiro¹; Taísa Beatriz Pacheco¹; António Fábio Carvalho da Silva¹; Clovis R. Maliska¹

¹ Universidade Federal de Santa Catarina

doi:10.20906/CPS/CILAMCE2015-0858

Resumo

The near-well regions require special attention in reservoir simulation due to the pronounced pressure gradients in those regions. Hence, the large pressure variation near the wells are rarely well captured with the commonly employed grid refinement. One of the leading goals of adopting hybrid grids is to capture the flow behavior in those regions with more accuracy. This paper presents two different approaches to deal with that situation. The first one treats the well-reservoir interface as a grid boundary. Then, as the grid gets closer to the well, it is demanded a severe refinement in the radial direction. The second approach employs a well model with the purpose of avoiding extremely refined grid. A single phase flow problem with a known well pressure value was solved in order to test the feasibility of these two approaches with several two-dimensional hybrid grids. The results are compared with a reference solution, which, regardless of also being numerical, was solved in a highly refined grid, especially in the near-well area.

Palavras-chave: well; hybrid grids; grid refinment; well model