We investigate experimentally and numerically the effect of wettability on viscous-liquid impregnation into a single layer of woven fibers confined between the parallel plates. In our experiments, special attention is paid to the flow-front behaviors and the characteristic flow fields induced by the pressure difference attempted to the mold. We change the wettability between the fiber and viscous fluid by coating the bundles with fluorine-based coating agent. Correlation between the flow-front behaviors and void formation are indicated in terms of the capillary number $\mathrm{Ca}$, and of so-called modified capillary number ${\mathrm{Ca}}^{\prime }$ that incorporates the effect of the contact angle between the fiber and liquid, ${\theta }_{\mathrm{f}}$. Through our three dimensional multiphase simulations, the impregnation process is examined as functions of $\mathrm{Ca}$ and ${\mathrm{Ca}}^{\prime }$ by varying either of the characteristic velocity, the surface tension, the viscosity, or the contact angle. We illustrate that the wettability is a crucial factor to dominate the impregnation and void formation processes, and that the modified capillary number does not apparently measure the formation of the macrovoids.

我们在实验和数值上研究了润湿性对粘液浸渍到平行板之间的单层编织纤维中的影响。在我们的实验中，应特别注意由流向模具的压力差所引起的流前行为和特征流场。我们通过用氟基涂层剂涂布纤维束来改变纤维和粘性流体之间的润湿性。流动前沿行为与空隙形成之间的相关性用毛细管数表示$\mathrm{钙}$，以及所谓的修饰毛细管数 ${\mathrm{钙}}^{\prime }$ 结合了纤维和液体之间的接触角的影响， ${\theta }_{\mathrm{F}}$。通过我们的三维多相模拟，我们考察了浸渍过程与$\mathrm{钙}$ 和 ${\mathrm{钙}}^{\prime }$通过改变特征速度，表面张力，粘度或接触角。我们表明，润湿性是控制浸渍和空隙形成过程的关键因素，并且修改后的毛细管数显然不能测量大孔隙的形成。