RTM充模过程的自适应隐式控制体积法

ADAPTIVE IMPLICIT ALGORITHM FOR RTM MOLD FILLING SIMULATION

提出了一种基于界面更新的RTM充模分析的自适应隐式控制体积法。该隐式方法的迭代方法只对已注满结点进行求解,然后更新界面结点的体积函数以便决定是否要更新界面。依据“一时间步,一单元层”的思想,采用最小二乘递推法估算隐式方法的时间步长,并依据压力估算每个控制体积的半注满时间,从而可以重构任何时间的流动前锋。计算表明,本文方法极大地提高了隐式方法的适用性,并把RTM充模数值模拟的计算时间复杂度降到结点数的2阶。

An adaptive implicit algorithm was proposed for RTM mold filling simulation. The proposed implicit algorithm was based on the update of the interface in order to track the flow front. The governing equations of the filled nodes were solved to obtain the pressure distribution, and filling fractions of the front nodes were checked to determine if any node is needed to be added to the filled nodes or be removed from the filled nodes. Based on the criterion that the resin moves forward only one element-size distance at each time step, the Recursive Least Square （RLS） adaptive method was employed dynamically to update the time step. The half-filled time of control volumes was estimated by the pressures in order to construct the flow fronts at any given time. The case studies demonstrate that the adaptive implicit algorithm improves the performance and flexibility of the implicit algorithm. The computational time complexity of 2.5D is reduced to 2 order of the node number.