论文标题
粒子形状会影响微流体域中的沉降和分类行为
Particle Shape Influences Settling and Sorting Behavior in Microfluidic Domains
论文作者
论文摘要
我们提出了一个新的数值模型，以模拟静态流体中不同几何形状的离散个体或不同几何形状的颗粒的混合物及其流动流体中的流动轨迹。模拟揭示了各种粒子沉降轨迹，这是其几何形状和密度的函数。飞旋镖粒子的表面凹陷和矩形粒子的纵横比的影响对其沉降轨迹中振荡的周期性和振幅的影响被数值捕获。使用替代圆形颗粒沉降或流动非圆形颗粒的混合物被证明可将粒子速度误算0.9-2.2，并不准确地确定颗粒的轨迹。在具有不同形状和尺寸的颗粒的微流体室中，模拟表明，稳定的涡旋不一定总是控制粒子的捕获，较大的颗粒也不会选择性地始终如一地陷入稳定的涡旋中。令人惊讶的是，大颗粒的形状从圆形到椭圆形的变化导致较小的圆形颗粒的诱捕性更强，但增强了较大颗粒的流出，这可能是一种基于微流体的替代方法，用于分类和分离不同尺寸和形状的颗粒。
We present a new numerical model to simulate settling trajectories of discretized individual or a mixture of particles of different geometrical shapes in a quiescent fluid and their flow trajectories in a flowing fluid. Simulations unveiled diverse particle settling trajectories as a function of their geometrical shape and density. The effects of the surface concavity of a boomerang particle and aspect ratio of a rectangular particle on the periodicity and amplitude of oscillations in their settling trajectories were numerically captured. Use of surrogate circular particles for settling or flowing of a mixture of non-circular particles were shown to miscalculate particle velocities by a factor of 0.9-2.2 and inaccurately determine the particles' trajectories. In a microfluidic chamber with particles of different shapes and sizes, simulations showed that steady vortices do not necessarily always control particle entrapments, nor do larger particles get selectively and consistently entrapped in steady vortices. Strikingly, a change in the shape of large particles from circular to elliptical resulted in stronger entrapments of smaller circular particles, but enhanced outflows of larger particles, which could be an alternative microfluidics-based method for sorting and separation of particles of different sizes and shapes.
