CAJ | 학술논문

=:在轴对称坐标系下,采用有限体积法求解液滴形成的N-S方程,运用Ansys 13.0中的VOF (Volume of Fluid)方法对重力作用下,流体在微管口液滴形成过程进行数值模拟,采用PLIC (Piecewise Linear Interface Construction)的几何重构方法成功捕捉液滴形成、变化与脱落过程的气液交界面,得到与实验相一致的研究结果,表明建模方法可行.分析了速度对液滴运动过程的影响,在颈缩阶段,入流速度决定流体内部速度,轴线压力呈线性增加趋势;断裂阶段,重力决定流体内部速度,轴线压力与速度波动趋势一致,最后得到无量纲数A (液滴完整长度与管内径比)和We的关联式8.611 A We+2.98.
=:재축대칭좌표계하,채용유한체적법구해액적형성적N-S방정,운용Ansys 13.0중적VOF (Volume of Fluid)방법대중력작용하,류체재미관구액적형성과정진행수치모의,채용PLIC (Piecewise Linear Interface Construction)적궤하중구방법성공포착액적형성、변화여탈락과정적기액교계면,득도여실험상일치적연구결과,표명건모방법가행.분석료속도대액적운동과정적영향,재경축계단,입류속도결정류체내부속도,축선압력정선성증가추세;단렬계단,중력결정류체내부속도,축선압력여속도파동추세일치,최후득도무량강수A (액적완정장도여관내경비)화We적관련식8.611 A We+2.98.
The Finite Volume Method was adopted to get the N-S equation of the liquid drop formation in the axisymmetric coordinate system. With the Volume of Fluid(VOF) Method in Ansys 13.0, the drop forming process at capillary tube under the influence of gravity was simulated. The gas-liquid interfaces of the formation, change and detachment of the liquid drop were captured by using the geometric reconstruction method of the piecewise linear interface construction (PLIC). The simulation results are strictly consistent with the experimental results, which proves the practicality of this numerical simulation. The influence of inflow velocity on the liquid drop’s motion process was analyzed. In the necking stage, internal velocity of fluid is determined by inflow velocity, and axial pressure presents a trend of linear increase. In the pinch stage, internal velocity of fluid is determined by gravity, and axial pressure is in accordance with velocity perturbation. Finally, the correlation formula of dimensionless number A (the ratio of drop’s full length to the internal diameter of tube) and We was achieved as: 8.611=A We+2.98 .