标题： 使用磁流变流体的动态密封 显示英文标题

标题： Dynamic Sealing Using Magneto-Rheological Fluids

摘要： 微型泵是微流体组件，广泛用于化学分析、生物传感和微机器人等应用。 然而，开发微型泵的一个障碍是其效率相对于宏观尺度的泵来说非常低。 本文提出了一种动态密封方法，用于外部齿轮泵，通过使用磁流变（MR）流体来减少齿轮齿顶与泵壳之间的间隙造成的体积损失。 通过减轻这些损失，我们能够在当前的机械结构和制造公差下实现高效率和高体积精度。 对使用磁流变流体的静态和动态密封进行了理论和实验研究。 两个马森数$Mn\left(p\right)$和$Mn\left(\Omega\right)$，分别根据流动的压力梯度和移动边界的速度定义，用于表征和评估密封性能。 探索了不同强度的磁场以确定最佳的密封效果，其中效果通过体积损失与摩擦因子的比值进行评估。 最后，我们在不同的工作条件下量化了这种动态密封方法在齿轮泵中的效果。 显示英文摘要

摘要： Micropumps are microfluidic components which are widely used in applications such as chemical analysis, biological sensing and micro-robots. However, one obstacle in developing micropumps is the extremely low efficiency relative to their macro-scale counterparts. This paper presents a dynamic sealing method for external gear pumps to reduce the volumetric losses through the clearance between the tips of gears and the housing by using magneto-rheological (MR) fluids. By mitigating these losses, we are able to achieve high efficiency and high volumetric accuracy with current mechanical architectures and manufacturing tolerances. Static and dynamic sealing using MR fluids are investigated theoretically and experimentally. Two Mason numbers $Mn\left(p\right)$ and $Mn\left(\Omega\right)$ which are defined in terms of pressure gradient of the flow and velocity of the moving boundary respectively are used to characterize and evaluate the sealing performance. A range of magnetic field intensities is explored to determine optimal sealing effectiveness, where effectiveness is evaluated using the ratio of volumetric loss and friction factor. Finally, we quantify the effectiveness of this dynamic sealing method under different working conditions for gear pumps.