Dou Xiaoxiao, Chen Zhewen, Cao Xiaojian, Ma Chicheng, Liu Jianlin
College of Pipeline and Civil Engineering, China University of Petroleum (East China), Qingdao 266580, China.
ACS Omega. 2022 Jul 21;7(30):26473-26482. doi: 10.1021/acsomega.2c02444. eCollection 2022 Aug 2.
Magnetic fluid is a new type of smart material, which holds implications for highly enhancing the oil displacement efficiency. In the present study, we perform a comprehensive investigation to probe the influence of a magnetic fluid on the displacement efficiency in porous media under the action of magnetic force. First, the displacement efficiency is measured by a self-developed setup, where factors such as the magnet thicknesses, the volume of the fluid injected, the fluid injection speed, and the porosity of the sample are surveyed as controllable variables. Moreover, the experimental results are well verified by the scaling laws according to the principle of dimensional balance. Next, a numerical simulation is performed to explore the detailed displacement process. First, the magnetic force generated by the ring magnet is calculated. Then, the function curves of the displacement efficiency with respect to the controlling variables are validated by the numerical simulation. In addition, the numerical simulation also demonstrates the volume phase distribution, the pressure field, and the velocity field of the mixed fluid during the displacement process. The simulation results are in excellent agreement with the experimental data. These findings are beneficial for us to better understand the oil displacement with the aid of external fields, which also provide inspiration for the areas of microfluidics, diffusion of pollutants, microsensors, etc.
磁流体是一种新型智能材料，对大幅提高驱油效率具有重要意义。在本研究中，我们进行了全面调查，以探究磁流体在磁力作用下对多孔介质中驱替效率的影响。首先，通过自行开发的装置测量驱替效率，其中将磁体厚度、注入流体体积、流体注入速度和样品孔隙率等因素作为可控变量进行研究。此外，根据量纲平衡原理，通过标度律对实验结果进行了充分验证。接下来，进行了数值模拟以探究详细的驱替过程。首先，计算环形磁体产生的磁力。然后，通过数值模拟验证了驱替效率相对于控制变量的函数曲线。此外，数值模拟还展示了驱替过程中混合流体的体积相分布、压力场和速度场。模拟结果与实验数据高度吻合。这些发现有助于我们更好地理解借助外部场进行的驱油过程，也为微流体、污染物扩散、微传感器等领域提供了启示。
