Electromagnetic wave is a viable means of introducing energy into reservoirs for the recovery of residual oil. However, previous studies have not considered the precise frequency of the electromagnetic (EM) wave. These studies focused on EM heating, not considering the efficiency dependence of EM transmitter and EM propagation on the EM properties of the medium. Thus, sandstone effective permittivity was experimentally measured, and electrical conductivity calculated for different saturation stages encountered in the nanofluid enhanced oil recovery process. The effective permittivity at the resonant frequency of the sandstone increased from 10.94 to 19.1 with a simultaneous frequency shift from 1.2 to 0.6 GHz due to the inclusion of magnetite nanofluid. This implies that the maximum transfer of EM energy for stimulation and activation of injected nanofluid can be achieved by irradiating the EM wave of this frequency within the reservoir for mobilization of the residual oil.

电磁波是将能量引入储层以回收残余油的可行方法。但是，以前的研究没有考虑电磁（EM）波的精确频率。这些研究集中在EM加热上，没有考虑EM发射器的效率依赖性和EM传播对介质EM特性的影响。因此，通过实验测量了砂岩的有效介电常数，并针对纳米流体增强采油过程中遇到的不同饱和阶段计算了电导率。由于包含磁铁矿纳米流体，在砂岩共振频率下的有效介电常数从10.94增加到19.1，同时频率从1.2转移到0.6 GHz。