## 4 Discussion  
This study took into account the benefits of combining LSW with NF as well as the problems associated with NF flooding and LSW, such as sweep efficiency and the influence of wettability alteration. Then, to increase the effectiveness of low-salinity flooding, a novel hybrid EOR technique of combining LSW with NF to alter the wettability of the rock surface was presented. This technique is known as LSWNF (low-salinity water + nanofluid) flooding. Throughout this research, various experimental methods were employed to analyze the effects of different concentrations of low-salinity water and nanofluids on wettability alteration and enhanced oil recovery. The results demonstrated that the composition with KCl-1+NF outperformed other compositions in terms of wettability alteration and enhanced oil recovery. This finding indicates that a specific combination of LSW and NF can have a significant impact on improving oil recovery efficiency. The most significant findings and accomplishments from this research include the following.  
First, nanofluids can alter the wettability of the reservoir rock further, enhancing the displacement of oil by water. The nanoparticles in the nanofluids interact with the rock surface, modifying the surface properties and improving the spreading and penetration of the injected fluid. This leads to improved oil recovery by reducing the residual oil saturation and increasing the sweep efficiency.  
Second, the presence of nanoparticles in the nanofluids can also exhibit unique fluid behavior, such as reduced viscosity and increased thermal conductivity. These properties can enhance the fluid flow within the reservoir, allowing for better fluid mobility and improved displacement of oil. The reduced viscosity of the nanofluids can mitigate the challenges of a high mobility ratio between injected fluids and the reservoir oil, resulting in more efficient oil displacement.  
Furthermore, the hybridization of nanofluids and low-salinity water can potentially address the issue of water channeling. The nanoparticles in the nanofluids can act as solid diverting agents, plugging the high-permeability zones and redirecting the injected fluids into the low-permeability areas. This helps in achieving a more uniform sweep of the reservoir, preventing the bypassing of oil and improving overall oil recovery efficiency.  
Both NF and LSW have a positive impact on the wettability alteration of the rock surface. However, oil binds to the rock surface as KCl and SiO\({}_{2}\) concentrations rise. As a result, choosing compositions with lower LSW and NF concentrations is a smart practice.  
The KCl-1+NF injection pattern from the core flooding trials produced the maximum residual oil recovery, which was followed by the KCl-2 and pure water injection patterns. The presence of NF has been shown to increase the amount of oil that can be collected, since it increases the mobility and sweep efficiency of the residual oil. Additionally, it was discovered that the KCl injection pattern produced the maximum recovery for the same interval. Its high wettability variations are the cause of this.  
The magnetic resonance images and the T2 spectrum test results obtained from the NMR investigations may demonstrate the migration properties of LSW + NF in heterogeneous cores, and the displacement of the solution in different porosities. The results  
Figure 9: Water saturation during injection in various kinds of pores: (**a**) small (\(\varphi\)24.7%); (**b**) medium (\(\varphi\)25.5%); (**c**) large (\(\varphi\)27.3%).  
showed that due to the initial injection stage's low flow resistance, the saturation in big pores increased quickly. At 15.0 PV, the saturation increased slightly to 95.8%. At 15 PV, the medium pores' occupation climbed gradually to 91.5%.