p Maroufi - EOR Research Center, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
h Rahmanifard - EOR Research Center, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
sh Ayatollahi - EOR Research Center, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
a Jahanmiri - EOR Research Center, School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran

Naturally fractured reservoirs (NFRs) contribute in large extent of oil and gas production to the ever increasing market demand of fossil energy. It is believed that waterflooding can more thandouble the recoverable reserves of many developed oilfields especially the fractured ones at low capital investment. Hence, as the methodological plan of this study, unconsolidated packed models of cylindrical geometry surrounded by fractures are utilized in order to perform a series of flowvisualization experiments during which the contribution of different parameters such as the extent of matrix wettability (water-wet, oil-wet, fractional wet and mixed wet), absolute permeability, and the physical oil properties (e.g., density, and viscosity) is studied. The results show that therecovery efficiency from water-wet media is higher than other cases. Furthermore, by decreasing the model permeability and increasing the oil viscosity during secondary recovery process, the recovery efficiency reduces

Waterflooding, Fractured reservoirs, Wettability, permeability, Viscosity