Analysis of Axial Meniscus Jump-Like Transition in Rectangular Microgrooves

The meniscus receding process was studied for the axial steady flow in open rectangular microgrooves based on experimental results. Experimental results show that the liquid film recedes remarkably as a cubic trendline from the accommodation stage to the bottom corner-flow stage, but the dead zone and the step change don’t exist. The receding process of the liquid film between the accommodation stage and the bottom corner-flow stage is named jump-like transition in the paper. Characteristics of the axial flow in rectangular microgrooves were theoretically analyzed considering the meniscus receding performance in the jump-like transition, calculation results show that radius of the meniscus curvature decreases along the groove axis, which provides drive for the axial flow; the liquid cross sectional area and the liquid height decrease evidently at the stage of the jump-like transition; the liquid velocity increases along the axis, and increases promptly at the transition stage and the corner flow stage.