Interfacial tension (IFT) reduction is widely acknowledged as one of the prominent oil recovery mechanism during nanofluid flooding enhanced oil recovery (EOR). Hence, in this work, an investigation of IFT at the crude oil-nanofluids interfaces was carried out using the Wilhelmy plate method in the presence of electromagnetic (EM) field. EM wave propagation within sandstone saturated with oil and nanofluids were simulated using COMSOL Multiphysics solver. A dielectric (ZnO) and magnetic (Fe₂O₃) nanoparticles were synthesized, and their EM properties as well as IFT reduction ability were measured. The superior EM properties of Fe₂O₃ nanoparticle contribute to its maximum IFT reduction of 6.13% of the crude oil-nanofluid interface under EM wave. The presence of Fe₂O₃ nanoparticles in sandstone saturated with oil and Fe₂O₃ nanofluid increases the sandstone response to EM wave. This is shown by reflection loss peak of −19.9 dB, equivalent to approximately 99% absorption of the EM wave at 1 GHz, with a matched impedance of 46.5 Ω. Hence, EM-assisted nanofluid flooding experiment conducted with bespoke core flooding system shows that oil recovery increased by 13.6% over the case without EM propagation during Fe₂O₃ nanoflooding. This could be attributed to increased fluid mobility in the sandstone due to IFT alteration and high EM response of the sandstone core. This result shows the potential application of magnetic nanofluid coupled with EM wave for enhanced oil recovery.

降低界面张力（IFT）是纳米流体驱提高采收率（EOR）期间最重要的采油机理之一。因此，在这项工作中，在电磁场（EM）的存在下，使用Wilhelmy平板法对原油-纳米流体界面处的IFT进行了研究。使用COMSOL Multiphysics求解器模拟了在油和纳米流体饱和的砂岩中的EM波传播。合成了电介质（ZnO）和磁性（Fe ₂ O ₃）纳米粒子，并测量了它们的EM性能以及IFT还原能力。Fe ₂ O ₃的优异电磁性能在电磁波作用下，纳米颗粒的最大IFT降低为原油-纳米流体界面的6.13％。Fe ₂ O ₃纳米颗粒存在于饱和油和Fe ₂ O ₃纳米流体的砂岩中，会增加砂岩对电磁波的响应。反射损耗峰值为-19.9 dB，相当于EM波在1 GHz处的吸收率约为99％，匹配阻抗为46.5Ω。因此，在定制的岩心驱替体系下进行的EM辅助纳米流体驱替实验表明，在Fe ₂ O ₃扩散过程中，没有EM传播的情况下，采油率提高了13.6％。纳米驱。这可能归因于砂岩岩心的IFT改变和高EM响应，从而增加了砂岩中的流体流动性。该结果表明磁性纳米流体与EM波耦合在提高采油率方面的潜在应用。